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Université de Sherbrooke
1.
Bernard, Francis.
Méthodes d'analyse des données incomplètes incorporant l'incertitude attribuable aux valeurs manquantes
.
Degree: 2013, Université de Sherbrooke
URL: http://hdl.handle.net/11143/6571
► Lorsqu'on réalise une analyse des données dans le cadre d'une enquête, on est souvent confronté au problème des données manquantes. L'une des solutions les plus…
(more)
▼ Lorsqu'on réalise une analyse des données dans le cadre d'une enquête, on est souvent confronté au problème des données manquantes. L'une des solutions les plus fréquemment utilisées est d'avoir recours aux méthodes d'
imputation simple. Malheureusement, ces méthodes souffrnt d'un handicap important : les estimations courantes basées sur les valeurs observées et imputées considèrent à tort les valeurs imputées comme des valeurs connues, bien qu'une certaine forme d'incertitude plane au sujet des valeurs à imputer. En particulier, les intervalles de confiance pour les paramètres d'intérêt basés sur les données ainsi complétées n'incorporent pas l'incertitude qui est attribuable aux valeurs manquantes. Les méthodes basées sur le rééchantillonnage et l'
imputation multiple – une généralisation de l'
imputation simple – s'avèrent toutes
deux des solutions courantes convenables au problème des données manquantes, du fait qu'elles incorporent cette incertitude. Une alternative consiste à avoir recours à l'
imputation multiple à
deux niveaux, une généralisation de l'
imputation multiple (conventionnelle) qui a été développée dans la thèse que Shen [51] a rédigée en 2000 et qui permet d'exploiter les situations où la nature des valeurs manquantes suggère d'effectuer la procédure d'
imputation en
deux étapes plutôt qu'en une seule. Nous décrirons ces méthodes d'analyse des données incomplètes qui incorporent l'incertitude attribuable aux valeurs manquantes, nous soulèverons quelques problématiques intéressantes relatives au recours à ces méthodes et nous y proposerons des solutions appropriées. Finalement, nous illustrerons l'application de l'
imputation multiple conventionnelle et de l'
imputation multiple à
deux niveaux au moyen d'exemples simples et concrets.
Advisors/Committee Members: Monga, Ernest (advisor).
Subjects/Keywords: Valeur manquante;
Incertitude;
Méthodes basées sur le rééchantillonnage;
Imputation multiple à deux niveaux;
Imputation multiple conventionnelle
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APA ·
Chicago ·
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APA (6th Edition):
Bernard, F. (2013). Méthodes d'analyse des données incomplètes incorporant l'incertitude attribuable aux valeurs manquantes
. (Masters Thesis). Université de Sherbrooke. Retrieved from http://hdl.handle.net/11143/6571
Chicago Manual of Style (16th Edition):
Bernard, Francis. “Méthodes d'analyse des données incomplètes incorporant l'incertitude attribuable aux valeurs manquantes
.” 2013. Masters Thesis, Université de Sherbrooke. Accessed December 08, 2019.
http://hdl.handle.net/11143/6571.
MLA Handbook (7th Edition):
Bernard, Francis. “Méthodes d'analyse des données incomplètes incorporant l'incertitude attribuable aux valeurs manquantes
.” 2013. Web. 08 Dec 2019.
Vancouver:
Bernard F. Méthodes d'analyse des données incomplètes incorporant l'incertitude attribuable aux valeurs manquantes
. [Internet] [Masters thesis]. Université de Sherbrooke; 2013. [cited 2019 Dec 08].
Available from: http://hdl.handle.net/11143/6571.
Council of Science Editors:
Bernard F. Méthodes d'analyse des données incomplètes incorporant l'incertitude attribuable aux valeurs manquantes
. [Masters Thesis]. Université de Sherbrooke; 2013. Available from: http://hdl.handle.net/11143/6571

University of Georgia
2.
Wang, Qun.
Investigation of multiple imputation procedures in the presence of missing quantitative and categorical variables.
Degree: MS, Statistics, 2004, University of Georgia
URL: http://purl.galileo.usg.edu/uga_etd/wang_qun_200408_ms
► The presence of missing or incomplete data is a ubiquitous problem in real world datasets. In the thesis, we apply multiple imputation procedures to analyze…
(more)
▼ The presence of missing or incomplete data is a ubiquitous problem in real world datasets. In the thesis, we apply
multiple imputation procedures to analyze incomplete multivariate datasets. We consider a dataset that contains both continuous and categorical variables, all with some missing values. While investigating three other
imputation methods, we propose a two-part combination model, which melds the general linear model and the logistic model together, to predict and impute the missing values. Based on R2 and half-bound criteria, we analyze the different effects on variability due to the proportion of data missing, due to the association structure of the missing data, and due to the
imputation procedure used.
Advisors/Committee Members: Jaxk Reeves.
Subjects/Keywords: multiple imputation
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Wang, Q. (2004). Investigation of multiple imputation procedures in the presence of missing quantitative and categorical variables. (Masters Thesis). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/wang_qun_200408_ms
Chicago Manual of Style (16th Edition):
Wang, Qun. “Investigation of multiple imputation procedures in the presence of missing quantitative and categorical variables.” 2004. Masters Thesis, University of Georgia. Accessed December 08, 2019.
http://purl.galileo.usg.edu/uga_etd/wang_qun_200408_ms.
MLA Handbook (7th Edition):
Wang, Qun. “Investigation of multiple imputation procedures in the presence of missing quantitative and categorical variables.” 2004. Web. 08 Dec 2019.
Vancouver:
Wang Q. Investigation of multiple imputation procedures in the presence of missing quantitative and categorical variables. [Internet] [Masters thesis]. University of Georgia; 2004. [cited 2019 Dec 08].
Available from: http://purl.galileo.usg.edu/uga_etd/wang_qun_200408_ms.
Council of Science Editors:
Wang Q. Investigation of multiple imputation procedures in the presence of missing quantitative and categorical variables. [Masters Thesis]. University of Georgia; 2004. Available from: http://purl.galileo.usg.edu/uga_etd/wang_qun_200408_ms

Victoria University of Wellington
3.
Luo, Maoxin.
Imputation on the Food, Nutrition and Environment Surveys 2007 and 2009 data.
Degree: 2013, Victoria University of Wellington
URL: http://hdl.handle.net/10063/2796
► The Food Nutrition Environment Survey (FNES) is a survey of New Zealand early childhood centres and schools and the food and nutritional services that they…
(more)
▼ The Food Nutrition Environment Survey (FNES) is a survey of New Zealand early childhood
centres and schools and the food and nutritional services that they provide for their
pupils. The 2007 and 2009 FNES surveys were managed by the Ministry of Health. Like all
the other social surveys, the FNES has the common problem of unit and item non-responses.
In other words, the FNES has missing data. In this thesis, we have surveyed a wide variety of
missing data handling techniques and applied most of them to the FNES datasets.
This thesis can be roughly divided into two parts. In the first part, we have studied and investigated
the different nature of missing data (i.e. missing data mechanisms), and all the common
and popular
imputation methods, using the Synthetic Unit Record File (SURF) which
has been developed by the Statistics New Zealand for educational purposes. By comparing
all those different
imputation methods, Bayesian
Multiple Imputation (MI) method is the preferred
option to impute missing data in terms of reducing non-response bias and properly
propagating
imputation uncertainty.
Due to the overlaps in the samples selected for the 2007 and 2009 FNES surveys, we
have discovered that the Bayesian MI can be improved by incorporating the matched dataset.
Hence, we have proposed a couple of new approaches to utilize the extra information from
the matched dataset. We believe that adapting the Bayesian MI to use the extra information
from the matched dataset is a preferable
imputation strategy for imputing the FNES missing
data. This is because the use of the matched dataset provides more prediction power to the
imputation model.
Advisors/Committee Members: Arnold, Richard.
Subjects/Keywords: Multiple imputation; Bayesian; Missing data
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Luo, M. (2013). Imputation on the Food, Nutrition and Environment Surveys 2007 and 2009 data. (Masters Thesis). Victoria University of Wellington. Retrieved from http://hdl.handle.net/10063/2796
Chicago Manual of Style (16th Edition):
Luo, Maoxin. “Imputation on the Food, Nutrition and Environment Surveys 2007 and 2009 data.” 2013. Masters Thesis, Victoria University of Wellington. Accessed December 08, 2019.
http://hdl.handle.net/10063/2796.
MLA Handbook (7th Edition):
Luo, Maoxin. “Imputation on the Food, Nutrition and Environment Surveys 2007 and 2009 data.” 2013. Web. 08 Dec 2019.
Vancouver:
Luo M. Imputation on the Food, Nutrition and Environment Surveys 2007 and 2009 data. [Internet] [Masters thesis]. Victoria University of Wellington; 2013. [cited 2019 Dec 08].
Available from: http://hdl.handle.net/10063/2796.
Council of Science Editors:
Luo M. Imputation on the Food, Nutrition and Environment Surveys 2007 and 2009 data. [Masters Thesis]. Victoria University of Wellington; 2013. Available from: http://hdl.handle.net/10063/2796

University of the Western Cape
4.
Karangwa, Innocent.
Imputation techniques for non-ordered categorical missing data
.
Degree: 2016, University of the Western Cape
URL: http://hdl.handle.net/11394/5061
► Missing data are common in survey data sets. Enrolled subjects do not often have data recorded for all variables of interest. The inappropriate handling of…
(more)
▼ Missing data are common in survey data sets. Enrolled subjects do not often have data recorded for all variables of interest. The inappropriate handling of missing data may lead to bias in the estimates and incorrect inferences. Therefore, special attention is needed when analysing incomplete data. The multivariate normal
imputation (MVNI) and the
multiple imputation by chained equations (MICE) have emerged as the best techniques to impute or fills in missing data. The former assumes a normal distribution of the variables in the
imputation model, but can also handle missing data whose distributions are not normal. The latter fills in missing values taking into account the distributional form of the variables to be imputed. The aim of this study was to determine the performance of these methods when data are missing at random (MAR) or completely at random (MCAR) on unordered or nominal categorical variables treated as predictors or response variables in the regression models. Both dichotomous and polytomous variables were considered in the analysis. The baseline data used was the 2007 Demographic and Health Survey (DHS) from the Democratic Republic of Congo. The analysis model of interest was the logistic regression model of the woman’s contraceptive method use status on her marital status, controlling or not for other covariates (continuous, nominal and ordinal). Based on the data set with missing values, data sets with missing at random and missing completely at random observations on either the covariates or response variables measured on nominal scale were first simulated, and then used for
imputation purposes. Under MVNI method, unordered categorical variables were first dichotomised, and then K − 1 (where K is the number of levels of the categorical variable of interest) dichotomised variables were included in the
imputation model, leaving the other category as a reference. These variables were imputed as continuous variables using a linear regression model.
Imputation with MICE considered the distributional form of each variable to be imputed. That is, imputations were drawn using binary and multinomial logistic regressions for dichotomous and polytomous variables respectively. The performance of these methods was evaluated in terms of bias and standard errors in regression coefficients that were estimated to determine the association between the woman’s contraceptive methods use status and her marital status, controlling or not for other types of variables. The analysis was done assuming that the sample was not weighted fi then the sample weight was taken into account to assess whether the sample design would affect the performance of the
multiple imputation methods of interest, namely MVNI and MICE. As expected, the results showed that for all the models, MVNI and MICE produced less biased smaller standard errors than the case deletion (CD) method, which discards items with missing values from the analysis. Moreover, it was found that when data were missing (MCAR or MAR) on the nominal variables that…
Advisors/Committee Members: Kotze, Danelle (advisor), Blignaut, Renette (advisor).
Subjects/Keywords: Missing data;
Multiple imputation;
Multiple imputation by chained equations;
Multivariate normal imputation
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Karangwa, I. (2016). Imputation techniques for non-ordered categorical missing data
. (Thesis). University of the Western Cape. Retrieved from http://hdl.handle.net/11394/5061
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Karangwa, Innocent. “Imputation techniques for non-ordered categorical missing data
.” 2016. Thesis, University of the Western Cape. Accessed December 08, 2019.
http://hdl.handle.net/11394/5061.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Karangwa, Innocent. “Imputation techniques for non-ordered categorical missing data
.” 2016. Web. 08 Dec 2019.
Vancouver:
Karangwa I. Imputation techniques for non-ordered categorical missing data
. [Internet] [Thesis]. University of the Western Cape; 2016. [cited 2019 Dec 08].
Available from: http://hdl.handle.net/11394/5061.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Karangwa I. Imputation techniques for non-ordered categorical missing data
. [Thesis]. University of the Western Cape; 2016. Available from: http://hdl.handle.net/11394/5061
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of the Western Cape
5.
Brydon, Humphrey Charles.
Missing imputation methods explored in big data analytics
.
Degree: 2018, University of the Western Cape
URL: http://hdl.handle.net/11394/6605
► The aim of this study is to look at the methods and processes involved in imputing missing data and more specifically, complete missing blocks of…
(more)
▼ The aim of this study is to look at the methods and processes involved in imputing missing data and more specifically, complete missing blocks of data. A further aim of this study is to look at the effect that the imputed data has on the accuracy of various predictive models constructed on the imputed data and hence determine if the
imputation method involved is suitable.
The identification of the missingness mechanism present in the data should be the first process to follow in order to identify a possible
imputation method. The identification of a suitable
imputation method is easier if the mechanism can be identified as one of the following; missing completely at random (MCAR), missing at random (MAR) or not missing at random (NMAR).
Predictive models constructed on the complete imputed data sets are shown to be less accurate for those models constructed on data sets which employed a hot-deck
imputation method. The data sets which employed either a single or
multiple Monte Carlo Markov Chain (MCMC) or the Fully Conditional Specification (FCS)
imputation methods are shown to result in predictive models that are more accurate.
The addition of an iterative bagging technique in the modelling procedure is shown to produce highly accurate prediction estimates. The bagging technique is applied to variants of the neural network, a decision tree and a
multiple linear regression (MLR) modelling procedure. A stochastic gradient boosted decision tree (SGBT) is also constructed as a comparison to the bagged decision tree.
Final models are constructed from 200 iterations of the various modelling procedures using a 60% sampling ratio in the bagging procedure. It is further shown that the addition of the bagging technique in the MLR modelling procedure can produce a MLR model that is more accurate than that of the other more advanced modelling procedures under certain conditions.
The evaluation of the predictive models constructed on imputed data is shown to vary based on the type of fit statistic used. It is shown that the average squared error reports little difference in the accuracy levels when compared to the results of the Mean Absolute Prediction Error (MAPE). The MAPE fit statistic is able to magnify the difference in the prediction errors reported. The Normalized Mean Bias Error (NMBE) results show that all predictive models constructed produced estimates that were an over-prediction, although these did vary depending on the data set and modelling procedure used.
The Nash Sutcliffe efficiency (NSE) was used as a comparison statistic to compare the accuracy of the predictive models in the context of imputed data. The NSE statistic showed that the estimates of the models constructed on the imputed data sets employing a
multiple imputation method were highly accurate. The NSE statistic results reported that the estimates from the predictive models constructed on the hot-deck imputed data were inaccurate and that a mean substitution of the fully observed data would have been a better method of
imputation.
The conclusion…
Advisors/Committee Members: Blignaut, Renette (advisor).
Subjects/Keywords: Missing data; Imputation methods; Multiple imputation; Neural network; Bagging
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Brydon, H. C. (2018). Missing imputation methods explored in big data analytics
. (Thesis). University of the Western Cape. Retrieved from http://hdl.handle.net/11394/6605
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Brydon, Humphrey Charles. “Missing imputation methods explored in big data analytics
.” 2018. Thesis, University of the Western Cape. Accessed December 08, 2019.
http://hdl.handle.net/11394/6605.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Brydon, Humphrey Charles. “Missing imputation methods explored in big data analytics
.” 2018. Web. 08 Dec 2019.
Vancouver:
Brydon HC. Missing imputation methods explored in big data analytics
. [Internet] [Thesis]. University of the Western Cape; 2018. [cited 2019 Dec 08].
Available from: http://hdl.handle.net/11394/6605.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Brydon HC. Missing imputation methods explored in big data analytics
. [Thesis]. University of the Western Cape; 2018. Available from: http://hdl.handle.net/11394/6605
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Oregon State University
6.
Amer, Safaa R.
Neural network imputation : a new fashion or a good tool.
Degree: PhD, Statistics, 2004, Oregon State University
URL: http://hdl.handle.net/1957/29926
► Most statistical surveys and data collection studies encounter missing data. A common solution to this problem is to discard observations with missing data while reporting…
(more)
▼ Most statistical surveys and data collection studies encounter missing data. A common
solution to this problem is to discard observations with missing data while reporting
the percentage of missing observations in different output tables.
Imputation is a tool
used to fill in the missing values. This dissertation introduces the missing data
problem as well as traditional
imputation methods (e.g. hot deck, mean
imputation,
regression, Markov Chain Monte Carlo, Expectation-Maximization, etc.). The use of
artificial neural networks (ANN), a data mining technique, is proposed as an effective
imputation procedure. During ANN
imputation, computational effort is minimized
while accounting for sample design and
imputation uncertainty. The mechanism and
use of ANN in
imputation for complex survey designs is investigated.
Imputation methods are not all equally good, and none are universally good. However,
simulation results and applications in this dissertation show that regression, Markov
chain Monte Carlo, and ANN yield comparable results. Artificial neural networks
could be considered as implicit models that take into account the sample design
without making strong parametric assumptions. Artificial neural networks make few
assumptions about the data, are asymptotically good and robust to multicollinearity
and outliers. Overall, ANN could be time and resources efficient for an experienced
user compared to other conventional
imputation techniques.
Advisors/Committee Members: Lesser, Virginia M. (advisor).
Subjects/Keywords: Multiple imputation (Statistics)
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Amer, S. R. (2004). Neural network imputation : a new fashion or a good tool. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/29926
Chicago Manual of Style (16th Edition):
Amer, Safaa R. “Neural network imputation : a new fashion or a good tool.” 2004. Doctoral Dissertation, Oregon State University. Accessed December 08, 2019.
http://hdl.handle.net/1957/29926.
MLA Handbook (7th Edition):
Amer, Safaa R. “Neural network imputation : a new fashion or a good tool.” 2004. Web. 08 Dec 2019.
Vancouver:
Amer SR. Neural network imputation : a new fashion or a good tool. [Internet] [Doctoral dissertation]. Oregon State University; 2004. [cited 2019 Dec 08].
Available from: http://hdl.handle.net/1957/29926.
Council of Science Editors:
Amer SR. Neural network imputation : a new fashion or a good tool. [Doctoral Dissertation]. Oregon State University; 2004. Available from: http://hdl.handle.net/1957/29926

University of Oxford
7.
Rombach, Ines.
The handling, analysis and reporting of missing data in patient reported outcome measures for randomised controlled trials.
Degree: PhD, 2016, University of Oxford
URL: http://ora.ox.ac.uk/objects/uuid:1d038192-69ca-4d34-9974-1bc092466dee
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.730437
► Missing data is a potential source of bias in the results of randomised controlled trials (RCTs), which can have a negative impact on guidance derived…
(more)
▼ Missing data is a potential source of bias in the results of randomised controlled trials (RCTs), which can have a negative impact on guidance derived from them, and ultimately patient care. This thesis aims to improve the understanding, handling, analysis and reporting of missing data in patient reported outcome measures (PROMs) for RCTs. A review of the literature provided evidence of discrepancies between recommended methodology and current practice in the handling and reporting of missing data. Particularly, missed opportunities to minimise missing data, the use of inappropriate analytical methods and lack of sensitivity analyses were noted. Missing data patterns were examined and found to vary between PROMs as well as across RCTs. Separate analyses illustrated difficulties in predicting missing data, resulting in uncertainty about assumed underlying missing data mechanisms. Simulation work was used to assess the comparative performance of statistical approaches for handling missing available in standard statistical software. Multiple imputation (MI) at either the item, subscale or composite score level was considered for missing PROMs data at a single follow-up time point. The choice of an MI approach depended on a multitude of factors, with MI at the item level being more beneficial than its alternatives for high proportions of item missingness. The approaches performed similarly for high proportions of unit-nonresponse; however, convergence issues were observed for MI at the item level. Maximum likelihood (ML), MI and inverse probability weighting (IPW) were evaluated for handling missing longitudinal PROMs data. MI was less biased than ML when additional post-randomisation data were available, while IPW introduced more bias compared to both ML and MI. A case study was used to explore approaches to sensitivity analyses to assess the impact of missing data. It was found that trial results could be susceptible to varying assumptions about missing data, and the importance of interpreting the results in this context was reiterated. This thesis provides researchers with guidance for the handling and reporting of missing PROMs data in order to decrease bias arising from missing data in RCTs.
Subjects/Keywords: Multiple imputation; Missing data; Randomised controlled trials
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Rombach, I. (2016). The handling, analysis and reporting of missing data in patient reported outcome measures for randomised controlled trials. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:1d038192-69ca-4d34-9974-1bc092466dee ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.730437
Chicago Manual of Style (16th Edition):
Rombach, Ines. “The handling, analysis and reporting of missing data in patient reported outcome measures for randomised controlled trials.” 2016. Doctoral Dissertation, University of Oxford. Accessed December 08, 2019.
http://ora.ox.ac.uk/objects/uuid:1d038192-69ca-4d34-9974-1bc092466dee ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.730437.
MLA Handbook (7th Edition):
Rombach, Ines. “The handling, analysis and reporting of missing data in patient reported outcome measures for randomised controlled trials.” 2016. Web. 08 Dec 2019.
Vancouver:
Rombach I. The handling, analysis and reporting of missing data in patient reported outcome measures for randomised controlled trials. [Internet] [Doctoral dissertation]. University of Oxford; 2016. [cited 2019 Dec 08].
Available from: http://ora.ox.ac.uk/objects/uuid:1d038192-69ca-4d34-9974-1bc092466dee ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.730437.
Council of Science Editors:
Rombach I. The handling, analysis and reporting of missing data in patient reported outcome measures for randomised controlled trials. [Doctoral Dissertation]. University of Oxford; 2016. Available from: http://ora.ox.ac.uk/objects/uuid:1d038192-69ca-4d34-9974-1bc092466dee ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.730437

Wayne State University
8.
Grace, Tammy A.
The Impact Of Multiple Imputation On The Type Ii Error Rate Of The T Test.
Degree: PhD, Education Evaluation and Research, 2016, Wayne State University
URL: https://digitalcommons.wayne.edu/oa_dissertations/1536
► ABSTRACT THE IMPACT OF MULTIPLE IMPUTATION ON THE TYPE II ERROR RATE OF THE T TEST by TAMMY A. GRACE August 2016 Advisor: Shlomo…
(more)
▼ ABSTRACT
THE IMPACT OF
MULTIPLE IMPUTATION ON THE TYPE II ERROR RATE OF
THE T TEST
by
TAMMY A. GRACE
August 2016
Advisor: Shlomo Sawilowsky, PhD
Major: Evaluation and Research
Degree: Doctor of Philosophy
The National Academy of Science identified numerous high priority areas for missing data research. This study addresses several of those areas by systematically investigating the impact of
multiple imputation on the rejection rate of the independent samples t test under varying conditions of sample size, effect size, fraction of missing data, distribution shape, and alpha. In addition to addressing gaps in the missing data literature, this study also provides an overview of the
multiple imputation procedure, as implemented in SPSS, with a focus on the practical aspects and challenges of using this method.
Advisors/Committee Members: Shlomo Sawilowsky.
Subjects/Keywords: Multiple Imputation; T Test; Statistics and Probability
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Grace, T. A. (2016). The Impact Of Multiple Imputation On The Type Ii Error Rate Of The T Test. (Doctoral Dissertation). Wayne State University. Retrieved from https://digitalcommons.wayne.edu/oa_dissertations/1536
Chicago Manual of Style (16th Edition):
Grace, Tammy A. “The Impact Of Multiple Imputation On The Type Ii Error Rate Of The T Test.” 2016. Doctoral Dissertation, Wayne State University. Accessed December 08, 2019.
https://digitalcommons.wayne.edu/oa_dissertations/1536.
MLA Handbook (7th Edition):
Grace, Tammy A. “The Impact Of Multiple Imputation On The Type Ii Error Rate Of The T Test.” 2016. Web. 08 Dec 2019.
Vancouver:
Grace TA. The Impact Of Multiple Imputation On The Type Ii Error Rate Of The T Test. [Internet] [Doctoral dissertation]. Wayne State University; 2016. [cited 2019 Dec 08].
Available from: https://digitalcommons.wayne.edu/oa_dissertations/1536.
Council of Science Editors:
Grace TA. The Impact Of Multiple Imputation On The Type Ii Error Rate Of The T Test. [Doctoral Dissertation]. Wayne State University; 2016. Available from: https://digitalcommons.wayne.edu/oa_dissertations/1536

Rice University
9.
Berliner, Nathan K.
Using Multiple Imputation, Survival Analysis, And Propensity Score Analysis In Cancer Data With Missingness.
Degree: MA, Engineering, 2015, Rice University
URL: http://hdl.handle.net/1911/87747
► In this thesis multiple imputation, survival analysis, and propensity score analysis are combined in order to answer questions about treatment efficacy in cancer data with…
(more)
▼ In this thesis
multiple imputation, survival analysis, and propensity score analysis are combined in order to answer questions about treatment efficacy in cancer data with missingness. While each of these fields have been studied individually, there has been little work and analysis on using all three together. Starting with an incomplete dataset, the goal is to impute the missing data, and then run survival and propensity score analysis on each of the imputed datasets to answer clinically relevant questions. Along the way, many theoretical and analytical decisions are made and justified. The methodology is then applied to an observational cancer survival dataset of patients who have brain metastases from breast cancer to determine the effectiveness of chemotherapeutic and HER2-directed therapies.
Advisors/Committee Members: Hess, Kenneth (advisor), Vannucci, Marina (committee member), Scott, David (committee member), Guerra, Rudy (committee member), Shen, Yu (committee member).
Subjects/Keywords: Multiple Imputation; Survival Analysis; Causal Analysis
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Berliner, N. K. (2015). Using Multiple Imputation, Survival Analysis, And Propensity Score Analysis In Cancer Data With Missingness. (Masters Thesis). Rice University. Retrieved from http://hdl.handle.net/1911/87747
Chicago Manual of Style (16th Edition):
Berliner, Nathan K. “Using Multiple Imputation, Survival Analysis, And Propensity Score Analysis In Cancer Data With Missingness.” 2015. Masters Thesis, Rice University. Accessed December 08, 2019.
http://hdl.handle.net/1911/87747.
MLA Handbook (7th Edition):
Berliner, Nathan K. “Using Multiple Imputation, Survival Analysis, And Propensity Score Analysis In Cancer Data With Missingness.” 2015. Web. 08 Dec 2019.
Vancouver:
Berliner NK. Using Multiple Imputation, Survival Analysis, And Propensity Score Analysis In Cancer Data With Missingness. [Internet] [Masters thesis]. Rice University; 2015. [cited 2019 Dec 08].
Available from: http://hdl.handle.net/1911/87747.
Council of Science Editors:
Berliner NK. Using Multiple Imputation, Survival Analysis, And Propensity Score Analysis In Cancer Data With Missingness. [Masters Thesis]. Rice University; 2015. Available from: http://hdl.handle.net/1911/87747

University of Notre Dame
10.
Justin M. Luningham.
Evaluating Psychometric and Imputation-Based Methods for
Data Integration</h1>.
Degree: PhD, Psychology, 2018, University of Notre Dame
URL: https://curate.nd.edu/show/xd07gq70t5b
► IDA refers to combining data from independent studies into a concatenated dataset and analyzing the new data jointly (Curran & Hussong, 2009). IDA is…
(more)
▼ IDA refers to combining data from independent
studies into a concatenated dataset and analyzing the new data
jointly (Curran & Hussong, 2009). IDA is an alternative to
meta-analysis, which synthesizes summary statistics (such as effect
sizes or standardized parameter estimates) from
multiple studies.
Pooling data for research is not a new idea; however, it has seen
limited use in psychology. The IDA framework is innovative in its
use of different models and methods to account for heterogeneity
across different data sources. This dissertation evaluates the
performance of particular applications of IDA in the field of
behavior genetics, where meta-analysis is common practice. Behavior
genetics researchers often perform exhaustive searches across the
entire genome seeking genetic markers that are associated with an
observed outcome. Because there are millions of genetic markers,
and because even true gene associations have extremely tiny effect
sizes, genome-wide searches are often combined across
multiple
studies to increase statistical power. Regression coefficients from
tests of association are meta-analyzed, even though psychological
or behavioral outcomes may be defined differently across studies.
This dissertation tests the hypothesis that more precise
measurement of an integrated outcome, achieved through IDA, can
provide added power over typical meta-analysis in multi-study
genome-wide searches. In chapter 1, a general overview of the IDA
framework is discussed, genome-wide association studies are
presented, and IDA for genome-wide searches is presented. Chapter 2
covers a simulation study evaluating measurement model IDA using a
proposed bi-factor integration model. Chapter 3 covers simulation
studies investigating
multiple imputation IDA performance with a
novel
imputation model, namely, boosted decision trees as an
extension of single-tree
imputation. Chapter 4 presents an
application of IDA to the Aggression in Children: Unraveling
gene-environment interplay to inform Treatment and InterventiON
strategies (ACTION) Consortium, a large-scale collaboration of six
research projects studying the genetic underpinnings of aggression
in children.
Advisors/Committee Members: Gitta Lubke, Research Director.
Subjects/Keywords: Integrative Data Analysis; Multiple Imputation; Genetic
Consortia
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Luningham, J. M. (2018). Evaluating Psychometric and Imputation-Based Methods for
Data Integration</h1>. (Doctoral Dissertation). University of Notre Dame. Retrieved from https://curate.nd.edu/show/xd07gq70t5b
Chicago Manual of Style (16th Edition):
Luningham, Justin M.. “Evaluating Psychometric and Imputation-Based Methods for
Data Integration</h1>.” 2018. Doctoral Dissertation, University of Notre Dame. Accessed December 08, 2019.
https://curate.nd.edu/show/xd07gq70t5b.
MLA Handbook (7th Edition):
Luningham, Justin M.. “Evaluating Psychometric and Imputation-Based Methods for
Data Integration</h1>.” 2018. Web. 08 Dec 2019.
Vancouver:
Luningham JM. Evaluating Psychometric and Imputation-Based Methods for
Data Integration</h1>. [Internet] [Doctoral dissertation]. University of Notre Dame; 2018. [cited 2019 Dec 08].
Available from: https://curate.nd.edu/show/xd07gq70t5b.
Council of Science Editors:
Luningham JM. Evaluating Psychometric and Imputation-Based Methods for
Data Integration</h1>. [Doctoral Dissertation]. University of Notre Dame; 2018. Available from: https://curate.nd.edu/show/xd07gq70t5b
11.
Magalhães, Ismenia Blavatsky de.
Avaliação de redes Bayesianas para imputação em variáveis qualitativas e quantitativas.
Degree: PhD, Engenharia Mecânica, 2007, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/3/3132/tde-06072007-145922/
;
► Redes Bayesianas são estruturas que combinam distribuições de probabilidade e grafos. Apesar das redes Bayesianas terem surgido na década de 80 e as primeiras tentativas…
(more)
▼ Redes Bayesianas são estruturas que combinam distribuições de probabilidade e grafos. Apesar das redes Bayesianas terem surgido na década de 80 e as primeiras tentativas em solucionar os problemas gerados a partir da não resposta datarem das décadas de 30 e 40, a utilização de estruturas deste tipo especificamente para imputação é bem recente: em 2002 em institutos oficiais de estatística e em 2003 no contexto de mineração de dados. O intuito deste trabalho é o de fornecer alguns resultados da aplicação de redes Bayesianas discretas e mistas para imputação. Para isso é proposto um algoritmo que combina o conhecimento de especialistas e dados experimentais observados de pesquisas anteriores ou parte dos dados coletados. Ao empregar as redes Bayesianas neste contexto, parte-se da hipótese de que uma vez preservadas as variáveis em sua relação original, o método de imputação será eficiente em manter propriedades desejáveis. Neste sentido, foram avaliados três tipos de consistências já existentes na literatura: a consistência da base de dados, a consistência lógica e a consistência estatística, e propôs-se a consistência estrutural, que se define como sendo a capacidade de a rede manter sua estrutura na classe de equivalência da rede original quando construída a partir dos dados após a imputação. É utilizada pela primeira vez uma rede Bayesiana mista para o tratamento da não resposta em variáveis quantitativas. Calcula-se uma medida de consistência estatística para redes mistas usando como recurso a imputação múltipla para a avaliação de parâmetros da rede e de modelos de regressão. Como aplicação foram conduzidos experimentos com base nos dados de domicílios e pessoas do Censo Demográfico 2000 do município de Natal e nos dados de um estudo sobre homicídios em Campinas. Dos resultados afirma-se que as redes Bayesianas para imputação em atributos discretos são promissoras, principalmente se o interesse estiver em manter a consistência estatística e o número de classes da variável for pequeno. Já para outras características, como o coeficiente de contingência entre as variáveis, são afetadas pelo método à medida que se aumenta o percentual de não resposta. Nos atributos contínuos, a mediana apresenta-se mais sensível ao método.
Bayesian networks are structures that combine probability distributions with graphs. Although Bayesian networks initially appeared in the 1980s and the first attempts to solve the problems generated from the non-response date back to the 1930s and 1940s, the use of structures of this kind specifically for imputation is rather recent: in 2002 by official statistical institutes, and in 2003 in the context of data mining. The purpose of this work is to present some results on the application of discrete and mixed Bayesian networks for imputation. For that purpose, we present an algorithm combining knowledge obtained from experts with experimental data derived from previous research or part of the collected data. To apply Bayesian networks in this context, it is assumed that once the variables are…
Advisors/Committee Members: Cozman, Fabio Gagliardi.
Subjects/Keywords: Bayesian networks; Imputação; Imputação múltipla; Imputation; Missing data; Multiple imputation; Não resposta; Redes Bayesianas
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Magalhães, I. B. d. (2007). Avaliação de redes Bayesianas para imputação em variáveis qualitativas e quantitativas. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/3/3132/tde-06072007-145922/ ;
Chicago Manual of Style (16th Edition):
Magalhães, Ismenia Blavatsky de. “Avaliação de redes Bayesianas para imputação em variáveis qualitativas e quantitativas.” 2007. Doctoral Dissertation, University of São Paulo. Accessed December 08, 2019.
http://www.teses.usp.br/teses/disponiveis/3/3132/tde-06072007-145922/ ;.
MLA Handbook (7th Edition):
Magalhães, Ismenia Blavatsky de. “Avaliação de redes Bayesianas para imputação em variáveis qualitativas e quantitativas.” 2007. Web. 08 Dec 2019.
Vancouver:
Magalhães IBd. Avaliação de redes Bayesianas para imputação em variáveis qualitativas e quantitativas. [Internet] [Doctoral dissertation]. University of São Paulo; 2007. [cited 2019 Dec 08].
Available from: http://www.teses.usp.br/teses/disponiveis/3/3132/tde-06072007-145922/ ;.
Council of Science Editors:
Magalhães IBd. Avaliação de redes Bayesianas para imputação em variáveis qualitativas e quantitativas. [Doctoral Dissertation]. University of São Paulo; 2007. Available from: http://www.teses.usp.br/teses/disponiveis/3/3132/tde-06072007-145922/ ;

East Carolina University
12.
Siver, Sydney R.
Methods for Handling Missing Data for Multiple-Item Questionnaires.
Degree: 2017, East Carolina University
URL: http://hdl.handle.net/10342/6517
► Missing data is a common problem, especially in the social and behavioral sciences. Modern missing data methods are underutilized in the industrial/organizational psychology and human…
(more)
▼ Missing data is a common problem, especially in the social and behavioral sciences. Modern missing data methods are underutilized in the industrial/organizational psychology and human resource management literature. Recommendations for handling missing data and default options in software packages often use outdated, suboptimal methods for missing data. Resulting analyses tend to be biased, underpowered, or both. Best practice recommends for the handling of missing data includes the use of multiple imputation (MI) methods. However, this method is often ignored in favor of more convenient methods. For industrial/organizational psychologists, missing data is particularly problematic on multiple-item questionnaires, such as the Survey of Perceived Organizational Support (SPOS). Person mean imputation is one of the most common methods used to handle missing data on multiple-item questionnaires. However, it makes strong assumptions about the missing data mechanism and the underlying factor structure of a measure and should be avoided, particularly if there is a high rate of non-response. MI does not make the same assumptions as person mean imputation and may be a superior method when items are missing from a multiple-item questionnaire. Results indicate that PMI and MI provide similar results, however PMI may outperform MI when the number of variables is large.
Subjects/Keywords: person mean imputation; Monte Carlo; Missing observations (Statistics); Multiple imputation (Statistics); Questionnaires
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Siver, S. R. (2017). Methods for Handling Missing Data for Multiple-Item Questionnaires. (Thesis). East Carolina University. Retrieved from http://hdl.handle.net/10342/6517
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Siver, Sydney R. “Methods for Handling Missing Data for Multiple-Item Questionnaires.” 2017. Thesis, East Carolina University. Accessed December 08, 2019.
http://hdl.handle.net/10342/6517.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Siver, Sydney R. “Methods for Handling Missing Data for Multiple-Item Questionnaires.” 2017. Web. 08 Dec 2019.
Vancouver:
Siver SR. Methods for Handling Missing Data for Multiple-Item Questionnaires. [Internet] [Thesis]. East Carolina University; 2017. [cited 2019 Dec 08].
Available from: http://hdl.handle.net/10342/6517.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Siver SR. Methods for Handling Missing Data for Multiple-Item Questionnaires. [Thesis]. East Carolina University; 2017. Available from: http://hdl.handle.net/10342/6517
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

George Mason University
13.
Cheema, Jehanzeb.
Handling Missing Data in Educational Research Using SPSS
.
Degree: 2012, George Mason University
URL: http://hdl.handle.net/1920/7840
► This study looked at the effect of a number of factors such as the choice of analytical method, the handling method for missing data, sample…
(more)
▼ This study looked at the effect of a number of factors such as the choice of analytical
method, the handling method for missing data, sample size, and proportion of missing
data, in order to evaluate the effect of missing data treatment on accuracy of estimation.
In order to accomplish this a methodological approach involving simulated data was
adopted. One outcome of the statistical analyses undertaken in this study is the
formulation of easy-to-implement guidelines for educational researchers that allows one
to choose one of the following factors when all others are given: sample size, proportion
of missing data in the sample, method of analysis, and missing data handling method.
Advisors/Committee Members: Dimitrov, Dimiter M (advisor).
Subjects/Keywords: Imputation Method;
Item Non-Response;
Listwise Deletion;
Missing Data;
Multiple Imputation;
Missing Value
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Cheema, J. (2012). Handling Missing Data in Educational Research Using SPSS
. (Thesis). George Mason University. Retrieved from http://hdl.handle.net/1920/7840
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Cheema, Jehanzeb. “Handling Missing Data in Educational Research Using SPSS
.” 2012. Thesis, George Mason University. Accessed December 08, 2019.
http://hdl.handle.net/1920/7840.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Cheema, Jehanzeb. “Handling Missing Data in Educational Research Using SPSS
.” 2012. Web. 08 Dec 2019.
Vancouver:
Cheema J. Handling Missing Data in Educational Research Using SPSS
. [Internet] [Thesis]. George Mason University; 2012. [cited 2019 Dec 08].
Available from: http://hdl.handle.net/1920/7840.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Cheema J. Handling Missing Data in Educational Research Using SPSS
. [Thesis]. George Mason University; 2012. Available from: http://hdl.handle.net/1920/7840
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
14.
Maillet, Olivier.
Processus stochastiques et non-linéaires dans les systèmes nano-électro-mécaniques : Stochastic and non-linear processes in nano-electro-mechanical systems.
Degree: Docteur es, Physique de la matière condensée et du rayonnement, 2018, Grenoble Alpes
URL: http://www.theses.fr/2018GREAY009
► Dans cette thèse, nous étudions des systèmes nano-électro-mécaniques (NEMS) en conditions cryogéniques (de 30 mK à 30 K) sensibles à des conditions de fluctuations ou…
(more)
▼ Dans cette thèse, nous étudions des systèmes nano-électro-mécaniques (NEMS) en conditions cryogéniques (de 30 mK à 30 K) sensibles à des conditions de fluctuations ou de désordre. Les phénomènes fondamentaux étudiés sont omniprésents dans la physique des NEMS, et pour certains vont même au-delà avec des analogies vers d’autres disciplines de la physique, comme les transitions de phase ou la RMN.Dans la première partie de cette thèse, nous nous intéressons ainsi au bruit d'amplitude du NEMS, fournissant un exemple de mouvement Brownien dans un potentiel de confinement. Du fait de la non-linéarité géométrique intrinsèque au système, l'anharmonicité du potentiel transduit le mouvement Brownien de chaque mode mécanique en fluctuations des fréquences propres de résonance. Ainsi, nous observons expérimentalement un phénomène de diffusion spectrale, se traduisant par un élargissement et un décalage de la raie de résonance non-triviaux rendant compte de la compétition entre la diffusion de la phase de la réponse du mode due à la transduction, et les mécanismes de relaxation du mode fluctuant. Une approche par intégrale de chemin de la diffusion capture l'effet analytiquement. Un tel mécanisme altère la résonance d'un mode mécanique sans influer sur les échanges d'énergie avec le bain thermodynamique du mode. En outre, l'introduction d'une forte excitation sinusoïdale agit en retour sur les fluctuations hors équilibre via la non-linéarité, ralentissant la dynamique du système et comprimant ses fluctuations pour certains points critiques de l'espace des paramètres, près du ou dans le régime de la réponse bistable permise par la non-linéarité. Enfin, des expériences-modèles ont été réalisées afin de comprendre en détail la décohérence mécanique classique à l’aide d’un bruit en fréquence extrinsèque, réalisé à l’aide d’une grille couplée au NEMS.La deuxième partie de cette thèse explore plus en détail certains mécanismes microscopiques de relaxation d'énergie ou du bruit en fréquence interne d’un mode mécanique, encore partiellement incompris pour les NEMS. Nous considérons d’abord le cas d’une contribution extérieure, mais universelle, qui a pour origine le transfert d’impulsion entre le NEMS et le gaz présent dans la cellule expérimentale, ici l’hélium 4. Dans la limite des faibles densités, la théorie cinétique décrit la dissipation dans le gaz ballistique. De façon inattendue, nous observons aux plus basses pressions atteignables une déviation à la théorie. Nous montrons pour plusieurs températures et plusieurs échantillons que cette déviation s’échelonne avec le rapport entre le libre parcours moyen des atomes dans le gaz et la hauteur du NEMS vis-à-vis du fond de l’échantillon. Ce résultat est justifié par un modèle phénoménologique prenant en compte la réflexion diffusive des atomes du gaz sur le mur du fond, qui présente à petite échelle une structure désordonnée. Cette réflexion résulte en une déviation à la Maxwellienne près du fond, et donc en l’établissement d’un gradient de densité du gaz sur une longueur de l’ordre…
Advisors/Committee Members: Collin, Eddy (thesis director).
Subjects/Keywords: Nanomécanique; Fluctuations; Non-Linéarité; Basses températures; Systèmes à deux niveaux; Nanomechanics; Fluctuations; Nonlinearity; Low temperatures; Two level systems; 530
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Maillet, O. (2018). Processus stochastiques et non-linéaires dans les systèmes nano-électro-mécaniques : Stochastic and non-linear processes in nano-electro-mechanical systems. (Doctoral Dissertation). Grenoble Alpes. Retrieved from http://www.theses.fr/2018GREAY009
Chicago Manual of Style (16th Edition):
Maillet, Olivier. “Processus stochastiques et non-linéaires dans les systèmes nano-électro-mécaniques : Stochastic and non-linear processes in nano-electro-mechanical systems.” 2018. Doctoral Dissertation, Grenoble Alpes. Accessed December 08, 2019.
http://www.theses.fr/2018GREAY009.
MLA Handbook (7th Edition):
Maillet, Olivier. “Processus stochastiques et non-linéaires dans les systèmes nano-électro-mécaniques : Stochastic and non-linear processes in nano-electro-mechanical systems.” 2018. Web. 08 Dec 2019.
Vancouver:
Maillet O. Processus stochastiques et non-linéaires dans les systèmes nano-électro-mécaniques : Stochastic and non-linear processes in nano-electro-mechanical systems. [Internet] [Doctoral dissertation]. Grenoble Alpes; 2018. [cited 2019 Dec 08].
Available from: http://www.theses.fr/2018GREAY009.
Council of Science Editors:
Maillet O. Processus stochastiques et non-linéaires dans les systèmes nano-électro-mécaniques : Stochastic and non-linear processes in nano-electro-mechanical systems. [Doctoral Dissertation]. Grenoble Alpes; 2018. Available from: http://www.theses.fr/2018GREAY009

Université de Sherbrooke
15.
Normand-Lauzière, François.
Anomalies postprandiales du métabolisme des acides gras libres dans l'évolution naturelle du diabète de type 2
.
Degree: 2010, Université de Sherbrooke
URL: http://hdl.handle.net/11143/5545
► Le diabète de type 2 (DM2) représente un fléau qui guette les habitants du continent nord-américain et est en lien avec l'épidémie d'obésité que nous…
(more)
▼ Le diabète de type 2 (DM2) représente un fléau qui guette les habitants du continent nord-américain et est en lien avec l'épidémie d'obésité que nous vivons depuis quelques années. Cette pathologie à évolution lente fait intervenir
deux éléments physiopathologiques cardinaux, soient la résistance à l'insuline (RI) et la diminution de sécrétion d'insuline en réponse au glucose (GSIS). Ces
deux entités mèneront ultimement à l'hyperglycémie chronique par une atteinte directe de la régulation du métabolisme énergétique et de la physiologie de l'insuline. Plusieurs hypothèses de travail ont été mises de l'avant afin de tenter d'expliquer les dysfonctions métaboliques présentes chez ces patients. La surexposition des tissus non-adipeux aux acides gras libres (AGL), la lipotoxicité, est une candidate potentielle à l'identification d'une étiologie liée à la progression naturelle du diabète de type 2. Il est donc très pertinent d'étudier les effets lipotoxiques des AGL chez des sujets non-diabétiques enfants de
deux parents diabétiques, qui sont à haut risque de développer cette pathologie. Notre équipe a récemment déterminé que ces sujets présentaient une augmentation de l'apparition des AGL plasmatiques ainsi qu'une augmentation de leur oxydation au cours d'une élévation expérimentales des
niveaux d'AGL circulants. En conditions physiologiques, via l'ingestion d'un repas standardisé, les sujets non-diabétiques enfants de
deux parents diabétiques, tout comme les sujets diabétiques, montrent une hypertriglycéridémie postprandiale qui n'est pas corrigée lorsque les
niveaux de glucose sont contrôlés. De plus, ces sujets à haut risque de développer le DM2 ne se comportent pas comme les sujets diabétiques à ce qui à [i.e. a] trait aux
niveaux d'apparition des AGL et de leur oxydation, comme il aurait été attendu. Les sujets diabétiques présentent une nette élévation des
niveaux d'apparition et d'oxydation des AGL même si les
niveaux de glucose sont corrigés. Ces anomalies semblent fortement associées avec la présence d'une adiposité abdominale chez les sujets DM2. Ces résultats expérimentaux suggèrent donc que les enfants de
deux parents diabétiques ne possèdent pas encore les dysfonctions métaboliques qui mèneront ultimement à une surexposition des tissus non-adipeux aux acides gras libres via une augmentation de leur apparition plasmatique.
Advisors/Committee Members: Carpentier, André (advisor).
Subjects/Keywords: Niveaux d'apparition;
Oxydation;
Acides gras libres;
Tissu adipeux;
Lipotoxicité;
Résistance à l'insuline;
Enfants de deux parents diabétiques;
Diabète de type 2
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Normand-Lauzière, F. (2010). Anomalies postprandiales du métabolisme des acides gras libres dans l'évolution naturelle du diabète de type 2
. (Masters Thesis). Université de Sherbrooke. Retrieved from http://hdl.handle.net/11143/5545
Chicago Manual of Style (16th Edition):
Normand-Lauzière, François. “Anomalies postprandiales du métabolisme des acides gras libres dans l'évolution naturelle du diabète de type 2
.” 2010. Masters Thesis, Université de Sherbrooke. Accessed December 08, 2019.
http://hdl.handle.net/11143/5545.
MLA Handbook (7th Edition):
Normand-Lauzière, François. “Anomalies postprandiales du métabolisme des acides gras libres dans l'évolution naturelle du diabète de type 2
.” 2010. Web. 08 Dec 2019.
Vancouver:
Normand-Lauzière F. Anomalies postprandiales du métabolisme des acides gras libres dans l'évolution naturelle du diabète de type 2
. [Internet] [Masters thesis]. Université de Sherbrooke; 2010. [cited 2019 Dec 08].
Available from: http://hdl.handle.net/11143/5545.
Council of Science Editors:
Normand-Lauzière F. Anomalies postprandiales du métabolisme des acides gras libres dans l'évolution naturelle du diabète de type 2
. [Masters Thesis]. Université de Sherbrooke; 2010. Available from: http://hdl.handle.net/11143/5545
16.
Teyssier, Geoffrey.
Inequality of opportunity : measurement and impact on economic growth : Inégalité d'opportunité : mesure et effet sur la croissance économique.
Degree: Docteur es, Sciences économiques, 2017, Paris 1
URL: http://www.theses.fr/2017PA01E060
► Cette thèse porte sur la mesure de l'inégalité d'opportunité et son effet sur la croissance économique. Le Chapitre 1 étudie les propriétés axiomatiques de deux…
(more)
▼ Cette thèse porte sur la mesure de l'inégalité d'opportunité et son effet sur la croissance économique. Le Chapitre 1 étudie les propriétés axiomatiques de deux approches de mesure concurrentes. Dans les deux cas, la population est partitionnée en groupes rassemblant des personnes partageant les mêmes circonstances, ces déterminants de revenu que les individus ne peuvent choisir (ex. sexe ou milieu familial). L'inégalité d'opportunité est alors mesurée comme celle présente au sein d'une distribution contrefactuelle où chacun se voit attribuer le revenu représentatif de son groupe. La première approche considère la moyenne arithmétique comme revenu représentatif. Lorsque le nombre de groupes est grand et que leur taille est petite, ces moyennes sont peu précisément estimées. Afin de d'atténuer ce problème, la seconde approche, dite paramétrique, suppose que les circonstances n'ont pas d'effet d'interaction et remplace la moyenne arithmétique par la prédiction OLS du revenu régressé sur les circonstances. Le Chapitre 1 montre que la méthode paramétrique est faible d'un point de vue axiomatique. En particulier, elle ne respecte pas une version «entre-groupes» du principe des transferts. Le Chapitre 2 propose une méthodologie afin de contourner le manque actuel de micro-données sur les circonstances parentales, un déterminant majeur de l'inégalité d'opportunité. L'idée est d'utiliser 1 structure des enquêtes démographiques organisées autour de foyers afin de retrouver les circonstances parentales des adultes vivant avec leurs parents, puis d'utiliser une méthode d'ajustement statistique -l'imputation multiple -afin d'obtenir une mesure d'inégalité d'opportunité représentative de la population adulte dans son ensemble. Celle-ci est proche de la« vraie» inégalité d'opportunité, qui repose sur des questions directes à propos du milieu parental contenue dans l'enquête brésilienne du PNAD 1996. Le Chapitre 3 étudie empiriquement une récente explication quant au caractère peu concluant de la littérature empirique sur l'inégalité et la croissance: ce n'est pas l'inégalité de revenus qui compte pour la croissance mais ses deux composantes, à savoir l'inégalité d'opportunité et la composante résiduelle qu'est l'inégalité d'effort. Cette explication est validée au Brésil au niveau municipal durant la période 1980-2010, où le: inégalités d'opportunité et d'effort sont respectivement préjudiciables et bénéfiques à la croissance économique future, comme attendu. Leurs effets sont robustes et significatifs, contrairement à celui de l'inégalité total de revenus.
This thesis is about the measurement of inequality of opportunity and its impact on economic growth. Chapter 1 studies the axiomatic properties of two prominent measurement approaches. In both cases, the population is partitioned into groups of people sharing the same circumstances, those income determinants that are beyond individual control (e.g. sex or parental background) and that shape one's opportunities. Inequality of opportunity is then measured by applying a1…
Advisors/Committee Members: Poncet, Sandra (thesis director).
Subjects/Keywords: Inégalité de revenus; Inégalité d'opportunité; Croissance économique; Imputation multiple; Income inequality; Inequality of opportunity; Economic growth; Multiple imputation
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Teyssier, G. (2017). Inequality of opportunity : measurement and impact on economic growth : Inégalité d'opportunité : mesure et effet sur la croissance économique. (Doctoral Dissertation). Paris 1. Retrieved from http://www.theses.fr/2017PA01E060
Chicago Manual of Style (16th Edition):
Teyssier, Geoffrey. “Inequality of opportunity : measurement and impact on economic growth : Inégalité d'opportunité : mesure et effet sur la croissance économique.” 2017. Doctoral Dissertation, Paris 1. Accessed December 08, 2019.
http://www.theses.fr/2017PA01E060.
MLA Handbook (7th Edition):
Teyssier, Geoffrey. “Inequality of opportunity : measurement and impact on economic growth : Inégalité d'opportunité : mesure et effet sur la croissance économique.” 2017. Web. 08 Dec 2019.
Vancouver:
Teyssier G. Inequality of opportunity : measurement and impact on economic growth : Inégalité d'opportunité : mesure et effet sur la croissance économique. [Internet] [Doctoral dissertation]. Paris 1; 2017. [cited 2019 Dec 08].
Available from: http://www.theses.fr/2017PA01E060.
Council of Science Editors:
Teyssier G. Inequality of opportunity : measurement and impact on economic growth : Inégalité d'opportunité : mesure et effet sur la croissance économique. [Doctoral Dissertation]. Paris 1; 2017. Available from: http://www.theses.fr/2017PA01E060

Université Paris-Sud – Paris XI
17.
Marti soler, Helena.
Modélisation des données d'enquêtes cas-cohorte par imputation multiple : application en épidémiologie cardio-vasculaire : Modeling of case-cohort data by multiple imputation : application to cardio-vascular epidemiology.
Degree: Docteur es, Biostatistiques, 2012, Université Paris-Sud – Paris XI
URL: http://www.theses.fr/2012PA11T022
► Les estimateurs pondérés généralement utilisés pour analyser les enquêtes cas-cohorte ne sont pas pleinement efficaces. Or, les enquêtes cas-cohorte sont un cas particulier de données…
(more)
▼ Les estimateurs pondérés généralement utilisés pour analyser les enquêtes cas-cohorte ne sont pas pleinement efficaces. Or, les enquêtes cas-cohorte sont un cas particulier de données incomplètes où le processus d'observation est contrôlé par les organisateurs de l'étude. Ainsi, des méthodes d'analyse pour données manquant au hasard (MA) peuvent être pertinentes, en particulier, l'
imputation multiple, qui utilise toute l'information disponible et permet d'approcher l'estimateur du maximum de vraisemblance partielle.Cette méthode est fondée sur la génération de plusieurs jeux plausibles de données complétées prenant en compte les différents
niveaux d'incertitude sur les données manquantes. Elle permet d'adapter facilement n'importe quel outil statistique disponible pour les données de cohorte, par exemple, l'estimation de la capacité prédictive d'un modèle ou d'une variable additionnelle qui pose des problèmes spécifiques dans les enquêtes cas-cohorte. Nous avons montré que le modèle d'
imputation doit être estimé à partir de tous les sujets complètement observés (cas et non-cas) en incluant l'indicatrice de statut parmi les variables explicatives. Nous avons validé cette approche à l'aide de plusieurs séries de simulations: 1) données complètement simulées, où nous connaissions les vraies valeurs des paramètres, 2) enquêtes cas-cohorte simulées à partir de la cohorte PRIME, où nous ne disposions pas d'une variable de phase-1 (observée sur tous les sujets) fortement prédictive de la variable de phase-2 (incomplètement observée), 3) enquêtes cas-cohorte simulées à partir de la cohorte NWTS, où une variable de phase-1 fortement prédictive de la variable de phase-2 était disponible. Ces simulations ont montré que l'
imputation multiple fournissait généralement des estimateurs sans biais des risques relatifs. Pour les variables de phase-1, ils approchaient la précision obtenue par l'analyse de la cohorte complète, ils étaient légèrement plus précis que l'estimateur calibré de Breslow et coll. et surtout que les estimateurs pondérés classiques. Pour les variables de phase-2, l'estimateur de l'
imputation multiple était généralement sans biais et d'une précision supérieure à celle des estimateurs pondérés classiques et analogue à celle de l'estimateur calibré. Les résultats des simulations réalisées à partir des données de la cohorte NWTS étaient cependant moins bons pour les effets impliquant la variable de phase-2 : les estimateurs de l'
imputation multiple étaient légèrement biaisés et moins précis que les estimateurs pondérés. Cela s'explique par la présence de termes d'interaction impliquant la variable de phase-2 dans le modèle d'analyse, d'où la nécessité d'estimer des modèles d'
imputation spécifiques à différentes strates de la cohorte incluant parfois trop peu de cas pour que les conditions asymptotiques soient réunies.Nous recommandons d'utiliser l'
imputation multiple pour obtenir des estimations plus précises des risques relatifs, tout en s'assurant qu'elles sont analogues à celles fournies par les analyses…
Advisors/Committee Members: Chavance, Michel (thesis director).
Subjects/Keywords: Enquêtes cas-cohorte; Estimateurs pondérés; Imputation multiple; Capacité prédictive; Case-cohort surveys; Weighted estimators; Multiple imputation; Predictive ability
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Marti soler, H. (2012). Modélisation des données d'enquêtes cas-cohorte par imputation multiple : application en épidémiologie cardio-vasculaire : Modeling of case-cohort data by multiple imputation : application to cardio-vascular epidemiology. (Doctoral Dissertation). Université Paris-Sud – Paris XI. Retrieved from http://www.theses.fr/2012PA11T022
Chicago Manual of Style (16th Edition):
Marti soler, Helena. “Modélisation des données d'enquêtes cas-cohorte par imputation multiple : application en épidémiologie cardio-vasculaire : Modeling of case-cohort data by multiple imputation : application to cardio-vascular epidemiology.” 2012. Doctoral Dissertation, Université Paris-Sud – Paris XI. Accessed December 08, 2019.
http://www.theses.fr/2012PA11T022.
MLA Handbook (7th Edition):
Marti soler, Helena. “Modélisation des données d'enquêtes cas-cohorte par imputation multiple : application en épidémiologie cardio-vasculaire : Modeling of case-cohort data by multiple imputation : application to cardio-vascular epidemiology.” 2012. Web. 08 Dec 2019.
Vancouver:
Marti soler H. Modélisation des données d'enquêtes cas-cohorte par imputation multiple : application en épidémiologie cardio-vasculaire : Modeling of case-cohort data by multiple imputation : application to cardio-vascular epidemiology. [Internet] [Doctoral dissertation]. Université Paris-Sud – Paris XI; 2012. [cited 2019 Dec 08].
Available from: http://www.theses.fr/2012PA11T022.
Council of Science Editors:
Marti soler H. Modélisation des données d'enquêtes cas-cohorte par imputation multiple : application en épidémiologie cardio-vasculaire : Modeling of case-cohort data by multiple imputation : application to cardio-vascular epidemiology. [Doctoral Dissertation]. Université Paris-Sud – Paris XI; 2012. Available from: http://www.theses.fr/2012PA11T022

Université de Montréal
18.
Vallée, Audrey-Anne.
Estimation de la variance en présence de données imputées pour des plans de sondage à grande entropie
.
Degree: 2014, Université de Montréal
URL: http://hdl.handle.net/1866/11120
► Les travaux portent sur l’estimation de la variance dans le cas d’une non- réponse partielle traitée par une procédure d’imputation. Traiter les valeurs imputées comme…
(more)
▼ Les travaux portent sur l’estimation de la variance dans le cas d’une non- réponse partielle traitée par une procédure d’
imputation. Traiter les valeurs imputées comme si elles avaient été observées peut mener à une sous-estimation substantielle de la variance des estimateurs ponctuels. Les estimateurs de variance usuels reposent sur la disponibilité des probabilités d’inclusion d’ordre
deux, qui sont parfois difficiles (voire impossibles) à calculer. Nous proposons d’examiner les propriétés d’estimateurs de variance obtenus au moyen d’approximations des probabilités d’inclusion d’ordre
deux. Ces approximations s’expriment comme une fonction des probabilités d’inclusion d’ordre un et sont généralement valides pour des plans à grande entropie. Les résultats d’une étude de simulation, évaluant les propriétés des estimateurs de variance proposés en termes de biais et d’erreur quadratique moyenne, seront présentés.
Advisors/Committee Members: Haziza, David (advisor).
Subjects/Keywords: Imputation;
Non-réponse;
Estimation de la variance;
Entropie d'un plan de sondage;
Probabilités d'inclusion d'ordre deux;
Imputation;
Nonresponse;
Variance estimation;
Entropy of a sampling design;
Second-order inclusion probabilities
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Vallée, A. (2014). Estimation de la variance en présence de données imputées pour des plans de sondage à grande entropie
. (Thesis). Université de Montréal. Retrieved from http://hdl.handle.net/1866/11120
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Vallée, Audrey-Anne. “Estimation de la variance en présence de données imputées pour des plans de sondage à grande entropie
.” 2014. Thesis, Université de Montréal. Accessed December 08, 2019.
http://hdl.handle.net/1866/11120.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Vallée, Audrey-Anne. “Estimation de la variance en présence de données imputées pour des plans de sondage à grande entropie
.” 2014. Web. 08 Dec 2019.
Vancouver:
Vallée A. Estimation de la variance en présence de données imputées pour des plans de sondage à grande entropie
. [Internet] [Thesis]. Université de Montréal; 2014. [cited 2019 Dec 08].
Available from: http://hdl.handle.net/1866/11120.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Vallée A. Estimation de la variance en présence de données imputées pour des plans de sondage à grande entropie
. [Thesis]. Université de Montréal; 2014. Available from: http://hdl.handle.net/1866/11120
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Illinois – Chicago
19.
Helenowski, Irene B.
Multiple Imputation via a Semi-Parametric Probability Integral Transformation.
Degree: 2012, University of Illinois – Chicago
URL: http://hdl.handle.net/10027/8652
► In real data scenarios, the distribution of the data is often unknown. Therefore, methods for imputing data which relax distributional or model assumptions may be…
(more)
▼ In real data scenarios, the distribution of the data is often unknown. Therefore, methods for imputing data which relax distributional or model assumptions may be of great interest to investigators. Here, we propose semi-parametric approaches allowing us to relax distributional assumptions when imputing continuous data, multinomial or loglinear model assumptions when imputing binary data, and general location model assumptions when imputing mixed continuous and binary data. The nonparametric portion of our methods involves mapping data to normally distributed values via empirical cumulative distribution (eCDF) or quantile computation and the parametric portion involves
multiple imputation under the normality assumption via joint modeling. Applying our approaches to data generated under the MCAR mechanism and to real data from databases of the Northwestern University SPORE in Prostate Cancer (Grant: P50 Ca 090386) and New York City Health and Nutrition Survey gave promising results.
Advisors/Committee Members: Demirtas, Hakan (advisor).
Subjects/Keywords: multiple imputation; random number generation; empirical cumulative distribution function
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Helenowski, I. B. (2012). Multiple Imputation via a Semi-Parametric Probability Integral Transformation. (Thesis). University of Illinois – Chicago. Retrieved from http://hdl.handle.net/10027/8652
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Helenowski, Irene B. “Multiple Imputation via a Semi-Parametric Probability Integral Transformation.” 2012. Thesis, University of Illinois – Chicago. Accessed December 08, 2019.
http://hdl.handle.net/10027/8652.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Helenowski, Irene B. “Multiple Imputation via a Semi-Parametric Probability Integral Transformation.” 2012. Web. 08 Dec 2019.
Vancouver:
Helenowski IB. Multiple Imputation via a Semi-Parametric Probability Integral Transformation. [Internet] [Thesis]. University of Illinois – Chicago; 2012. [cited 2019 Dec 08].
Available from: http://hdl.handle.net/10027/8652.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Helenowski IB. Multiple Imputation via a Semi-Parametric Probability Integral Transformation. [Thesis]. University of Illinois – Chicago; 2012. Available from: http://hdl.handle.net/10027/8652
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Illinois – Chicago
20.
Nieh, Chiping.
Using Mass Balance, Factor Analysis, and Multiple Imputation to Assess Health Effects of Water Quality.
Degree: 2012, University of Illinois – Chicago
URL: http://hdl.handle.net/10027/8658
► This dissertation explores the use of three analytical methods to improve the utility of microbial water quality data, collected on the Chicago River from 2007…
(more)
▼ This dissertation explores the use of three analytical methods to improve the utility of microbial water quality data, collected on the Chicago River from 2007 to 2009, in predicting health risk among water users. The
Multiple Imputation(MI) method was applied to fill in microbial missing values and the ability of the method to reduce bias was evaluated, chemical mass balance model and exploratory factor analysis were then utilized to identify sources of fecal contamination in the river system. Sources Identified as contributing to fecal contamination were used in predicting health risk.
The results showed that by introducing a 2% bias to the parameter estimates, the MI method was able to recover 24% of missing data. However, in order to fill in 36% of missing values, 33% of bias was introduced. Chemical mass balance model and exploratory factor analysis both identified the water reclamation plant, combine sewer overflows (CSOs), and the precipitation as sources of fecal contamination in the river system. However, no association between pollutant sources and health risk were observed.
Advisors/Committee Members: Scheff, Peter A (advisor), Copyright 2011 Chiping Nieh (advisor).
Subjects/Keywords: Multiple imputation; factor analysis; chemical mass balance model; surface water quality
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Nieh, C. (2012). Using Mass Balance, Factor Analysis, and Multiple Imputation to Assess Health Effects of Water Quality. (Thesis). University of Illinois – Chicago. Retrieved from http://hdl.handle.net/10027/8658
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Nieh, Chiping. “Using Mass Balance, Factor Analysis, and Multiple Imputation to Assess Health Effects of Water Quality.” 2012. Thesis, University of Illinois – Chicago. Accessed December 08, 2019.
http://hdl.handle.net/10027/8658.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Nieh, Chiping. “Using Mass Balance, Factor Analysis, and Multiple Imputation to Assess Health Effects of Water Quality.” 2012. Web. 08 Dec 2019.
Vancouver:
Nieh C. Using Mass Balance, Factor Analysis, and Multiple Imputation to Assess Health Effects of Water Quality. [Internet] [Thesis]. University of Illinois – Chicago; 2012. [cited 2019 Dec 08].
Available from: http://hdl.handle.net/10027/8658.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Nieh C. Using Mass Balance, Factor Analysis, and Multiple Imputation to Assess Health Effects of Water Quality. [Thesis]. University of Illinois – Chicago; 2012. Available from: http://hdl.handle.net/10027/8658
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Washington University in St. Louis
21.
Murden, Raphiel.
Examining The Effectiveness Of Multiple Imputation: A Case Study On Hiv Risk Behaviors In Women Receiving Treatment For Substance Use Disorders.
Degree: MA, Mathematics, 2011, Washington University in St. Louis
URL: https://openscholarship.wustl.edu/etd/496
► Women in the United States are becoming infected with HIV more quickly now than ever before; many of whom are at higher risk because of…
(more)
▼ Women in the United States are becoming infected with HIV more quickly now than ever before; many of whom are at higher risk because of their substance use habits or that of their partners.: CDC, 2010) This study analyzes cross sectional data regarding the risk behaviors and addiction severity of a sample of women receiving treatment for substance use disorders: SUDs). The data was gathered between 2006 and 2010 at a women's substance use treatment center in St. Louis, Missouri: MO), the name of which cannot be disclosed. We develop a scale, the HIV Risk Scale: HRS), to quantify a woman's risk of contracting HIV at the time of presenting for rehabilitation based on self-reported sexual and drug behaviors. We then, using the seven interviewer-ratings of the Addiction Severity Index: ASI) as predictors of the HRS, examine the results of regression using two methods to adjust for missing data:: 1) case-wise deletion and: 2)
multiple imputation. Results suggest that using several of the ASI, a tool already implemented in rehabilitation efforts, interventions can be tailored to address more closely all of the issues regarding the health and safety of substance abusing women seeking relief from addiction. Results show that specifically looking at the interviewer's assessment of how severely addiction impacts legal, drug-related, alcohol-related, employment-related and medical aspects of a woman's life may enable treatment centers to help her alleviate the HIV to which she maybe exposed.
Advisors/Committee Members: Edward Spitznagel.
Subjects/Keywords: Statistics; Missing data, Multiple Imputation, HIV, Substance Use Disorder, Women
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Murden, R. (2011). Examining The Effectiveness Of Multiple Imputation: A Case Study On Hiv Risk Behaviors In Women Receiving Treatment For Substance Use Disorders. (Thesis). Washington University in St. Louis. Retrieved from https://openscholarship.wustl.edu/etd/496
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Murden, Raphiel. “Examining The Effectiveness Of Multiple Imputation: A Case Study On Hiv Risk Behaviors In Women Receiving Treatment For Substance Use Disorders.” 2011. Thesis, Washington University in St. Louis. Accessed December 08, 2019.
https://openscholarship.wustl.edu/etd/496.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Murden, Raphiel. “Examining The Effectiveness Of Multiple Imputation: A Case Study On Hiv Risk Behaviors In Women Receiving Treatment For Substance Use Disorders.” 2011. Web. 08 Dec 2019.
Vancouver:
Murden R. Examining The Effectiveness Of Multiple Imputation: A Case Study On Hiv Risk Behaviors In Women Receiving Treatment For Substance Use Disorders. [Internet] [Thesis]. Washington University in St. Louis; 2011. [cited 2019 Dec 08].
Available from: https://openscholarship.wustl.edu/etd/496.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Murden R. Examining The Effectiveness Of Multiple Imputation: A Case Study On Hiv Risk Behaviors In Women Receiving Treatment For Substance Use Disorders. [Thesis]. Washington University in St. Louis; 2011. Available from: https://openscholarship.wustl.edu/etd/496
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
22.
Liebenberg, Shawn Carl.
Multiple imputation in the presence of a detection limit, with applications : an empirical approach / Shawn Carl Liebenberg
.
Degree: 2014, North-West University
URL: http://hdl.handle.net/10394/15363
► Scientists often encounter unobserved or missing measurements that are typically reported as less than a fixed detection limit. This especially occurs in the environmental sciences…
(more)
▼ Scientists often encounter unobserved or missing measurements that are typically reported as less than a fixed detection limit. This especially occurs in the environmental sciences when detection of low exposures are not possible due to limitations of the measuring instrument, and the resulting data are often referred to as type I and II left censored data. Observations lying below this detection limit are therefore often ignored, or `guessed' because it cannot be measured accurately. However, reliable estimates of the population parameters are nevertheless required to perform statistical analysis. The problem of dealing with values below a detection limit becomes increasingly complex when a large number of observations are present below this limit. Researchers thus have interest in developing statistical robust estimation procedures for dealing with left- or right-censored data sets (SinghandNocerino2002). The aim of this study focuses on several main components regarding the problems mentioned above. The imputation of censored data below a fixed detection limit are studied, particularly using the maximum likelihood procedure of Cohen(1959), and several variants thereof, in combination with four new variations of the multiple imputation concept found in literature. Furthermore, the focus also falls strongly on estimating the density of the resulting imputed, `complete' data set by applying various kernel density estimators. It should be noted that bandwidth selection issues are not of importance in this study, and will be left for further research. In this study, however, the maximum likelihood estimation method of Cohen (1959) will be compared with several variant methods, to establish which of these maximum likelihood estimation procedures for censored data estimates the population parameters of three chosen Lognormal distribution, the most reliably in terms of well-known discrepancy measures. These methods will be implemented in combination with four new multiple imputation procedures, respectively, to assess which of these nonparametric methods are most effective with imputing the 12 censored values below the detection limit, with regards to the global discrepancy measures mentioned above. Several variations of the Parzen-Rosenblatt kernel density estimate will be fitted to the complete filled-in data sets, obtained from the previous methods, to establish which is the preferred data-driven method to estimate these densities. The primary focus of the current study will therefore be the performance of the four chosen multiple imputation methods, as well as the recommendation of methods and procedural combinations to deal with data in the presence of a detection limit. An extensive Monte Carlo simulation study was performed to compare the various methods and procedural combinations. Conclusions and recommendations regarding the best of these methods and combinations are made based on the study's results.
Subjects/Keywords: Multiple imputation;
Detection limit;
Maximum likelihood estimation;
Kernel density estimation;
Bootstrap
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Liebenberg, S. C. (2014). Multiple imputation in the presence of a detection limit, with applications : an empirical approach / Shawn Carl Liebenberg
. (Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/15363
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Liebenberg, Shawn Carl. “Multiple imputation in the presence of a detection limit, with applications : an empirical approach / Shawn Carl Liebenberg
.” 2014. Thesis, North-West University. Accessed December 08, 2019.
http://hdl.handle.net/10394/15363.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Liebenberg, Shawn Carl. “Multiple imputation in the presence of a detection limit, with applications : an empirical approach / Shawn Carl Liebenberg
.” 2014. Web. 08 Dec 2019.
Vancouver:
Liebenberg SC. Multiple imputation in the presence of a detection limit, with applications : an empirical approach / Shawn Carl Liebenberg
. [Internet] [Thesis]. North-West University; 2014. [cited 2019 Dec 08].
Available from: http://hdl.handle.net/10394/15363.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Liebenberg SC. Multiple imputation in the presence of a detection limit, with applications : an empirical approach / Shawn Carl Liebenberg
. [Thesis]. North-West University; 2014. Available from: http://hdl.handle.net/10394/15363
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Minnesota
23.
Medhanie, Amanuel Gebri.
The robustness of multilevel multiple imputation for handling missing data in hierarchical linear models.
Degree: PhD, Educational Psychology, 2013, University of Minnesota
URL: http://purl.umn.edu/155986
► Missing data often present problems for credible statistical analyses. Luckily there are valid methods for dealing with missing data but the context in which the…
(more)
▼ Missing data often present problems for credible statistical analyses. Luckily there are valid methods for dealing with missing data but the context in which the data are missing can impact the performance of these methods. Relatively little is known about the proper way to handle missing data in multilevel data structures. This study used a Monte Carlo simulation to compare the performance of three missing data methods on multilevel data (multilevel multiple imputation, multiple imputation ignoring the multilevel structure, and listwise deletion). The comparison of these methods was made under conditions known or believed to influence both the performance of missing data methods and multilevel modeling. The results suggest that listwise deletion performs well compared to multilevel multiple imputation but multiple imputation ignoring the multilevel structure performed poorly. The implications of these results for educational research are discussed.
Subjects/Keywords: Hierarchical linear models; Missing data; Multilevel; Multiple imputation; Nested data; PAN
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Medhanie, A. G. (2013). The robustness of multilevel multiple imputation for handling missing data in hierarchical linear models. (Doctoral Dissertation). University of Minnesota. Retrieved from http://purl.umn.edu/155986
Chicago Manual of Style (16th Edition):
Medhanie, Amanuel Gebri. “The robustness of multilevel multiple imputation for handling missing data in hierarchical linear models.” 2013. Doctoral Dissertation, University of Minnesota. Accessed December 08, 2019.
http://purl.umn.edu/155986.
MLA Handbook (7th Edition):
Medhanie, Amanuel Gebri. “The robustness of multilevel multiple imputation for handling missing data in hierarchical linear models.” 2013. Web. 08 Dec 2019.
Vancouver:
Medhanie AG. The robustness of multilevel multiple imputation for handling missing data in hierarchical linear models. [Internet] [Doctoral dissertation]. University of Minnesota; 2013. [cited 2019 Dec 08].
Available from: http://purl.umn.edu/155986.
Council of Science Editors:
Medhanie AG. The robustness of multilevel multiple imputation for handling missing data in hierarchical linear models. [Doctoral Dissertation]. University of Minnesota; 2013. Available from: http://purl.umn.edu/155986

University of Rochester
24.
Hebert, Donald Joseph.
Global Tests for Multiple Outcomes in Randomized
Trials.
Degree: PhD, 2016, University of Rochester
URL: http://hdl.handle.net/1802/31567
► Methods for analyses of multiple outcome variables in randomized trials are prevalent throughout the statistical literature. Research for the case where the interest is in…
(more)
▼ Methods for analyses of multiple outcome variables
in randomized trials are prevalent
throughout the statistical
literature. Research for the case where the interest is in
evaluating an overall treatment effect across the multiple outcomes
has received a
great deal of attention due to its importance in
practice. This thesis provides a
thorough review of current
approaches for the analyses of multiple outcomes and
suggests a
need for an approach that maintains high statistical power under
several
different alternatives of clinical interest. The proposed
methods aim to satisfy this
need in the cases of both multivariate
normal and mixed outcomes.
Multiple clinical outcomes are often
measured repeatedly over time and the problem
of missing data is
ubiquitous in clinical trials. Available methods to account for
missing data are discussed in relation to the three sources of
correlation stemming
from these outcomes in this multivariate
longitudinal context. This thesis suggests a
novel approach to
properly account for missing data when implementing the proposed
methods for analyses of the multiple clinical
outcomes.
Subjects/Keywords: Global testing; Multiples outcomes; Missing data; Linear combinations; Multiple imputation
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Hebert, D. J. (2016). Global Tests for Multiple Outcomes in Randomized
Trials. (Doctoral Dissertation). University of Rochester. Retrieved from http://hdl.handle.net/1802/31567
Chicago Manual of Style (16th Edition):
Hebert, Donald Joseph. “Global Tests for Multiple Outcomes in Randomized
Trials.” 2016. Doctoral Dissertation, University of Rochester. Accessed December 08, 2019.
http://hdl.handle.net/1802/31567.
MLA Handbook (7th Edition):
Hebert, Donald Joseph. “Global Tests for Multiple Outcomes in Randomized
Trials.” 2016. Web. 08 Dec 2019.
Vancouver:
Hebert DJ. Global Tests for Multiple Outcomes in Randomized
Trials. [Internet] [Doctoral dissertation]. University of Rochester; 2016. [cited 2019 Dec 08].
Available from: http://hdl.handle.net/1802/31567.
Council of Science Editors:
Hebert DJ. Global Tests for Multiple Outcomes in Randomized
Trials. [Doctoral Dissertation]. University of Rochester; 2016. Available from: http://hdl.handle.net/1802/31567

University of Adelaide
25.
Sullivan, Thomas Richard.
Multiple Imputation for Handling Missing Outcome Data.
Degree: 2017, University of Adelaide
URL: http://hdl.handle.net/2440/119248
► Background: Multiple imputation is a widely used approach to handling missing data. Despite a growing evidence base for its use, implementation in practical settings remains…
(more)
▼ Background:
Multiple imputation is a widely used approach to handling missing data. Despite a growing evidence base for its use, implementation in practical settings remains challenging. This thesis considers knowledge gaps in the application of
multiple imputation for handling missing outcome data. Research has shown that deleting observations with multiply imputed outcomes before analysis can be beneficial when
imputation and analysis models are the same. However, it is unclear how this approach performs with auxiliary variables, which are often available in practice. Another challenge arises when the outcome of interest is binary. The use of log binomial regression to produce relative risks is common, yet standard methods for imputing binary outcomes involve logistic regression or a multivariate normal assumption. It is uncertain whether inconsistencies between
imputation and analysis models in this setting lead to biased or inefficient estimation. Questions also remain concerning the utility of
multiple imputation in randomised trials. Unlike observational studies, the key exposure in randomised trials (randomised group) is always observed and independent of covariates for adjustment. If extended follow-up beyond completion of a randomised trial is planned, there may be more missing outcome data than in the original trial, and the use of eligibility restrictions and separate consent processes for participation in extended follow-up may complicate the use of
multiple imputation. Unfortunately little is known about the extent of missing outcome data in this setting. Aims: Specific aims are to: 1. Evaluate the effect of deleting imputed outcomes prior to analysis in the presence of auxiliary variables; 2. Investigate the performance of
multiple imputation when estimating the relative risk; 3. Assess the utility of
multiple imputation in randomised trials; 4. Summarise the extent of missing outcome data and provide guidance on the implementation of
multiple imputation in extended follow-up studies. Methods: The performance of
multiple imputation was evaluated using data simulation and application to a real clinical trial. To summarise the extent of missing outcome data in extended follow-up studies, a systematic review of published follow-up studies was undertaken. Results: Deleting imputed outcomes prior to analysis can lead to bias when the
imputation model contains auxiliary variables associated with missingness in the outcome. For relative risk estimation, standard
multiple imputation methods introduce bias and tend to produce confidence intervals that are too wide.
Multiple imputation performs well in randomised trials, but simpler unbiased alternative methods for handling missing data are often slightly more efficient. Missing outcome data are a considerable threat to the validity of conclusions from extended follow-up studies. Eligibility restrictions and separate consent processes for participation are commonly employed in this setting, making the implementation of
multiple imputation more challenging.…
Advisors/Committee Members: Salter, Amy (advisor), School of Public Health (school).
Subjects/Keywords: Multiple imputation; missing data; missing at random; clinical trials
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Sullivan, T. R. (2017). Multiple Imputation for Handling Missing Outcome Data. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/119248
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Sullivan, Thomas Richard. “Multiple Imputation for Handling Missing Outcome Data.” 2017. Thesis, University of Adelaide. Accessed December 08, 2019.
http://hdl.handle.net/2440/119248.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Sullivan, Thomas Richard. “Multiple Imputation for Handling Missing Outcome Data.” 2017. Web. 08 Dec 2019.
Vancouver:
Sullivan TR. Multiple Imputation for Handling Missing Outcome Data. [Internet] [Thesis]. University of Adelaide; 2017. [cited 2019 Dec 08].
Available from: http://hdl.handle.net/2440/119248.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Sullivan TR. Multiple Imputation for Handling Missing Outcome Data. [Thesis]. University of Adelaide; 2017. Available from: http://hdl.handle.net/2440/119248
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Arizona State University
26.
Mistler, Stephen Andrew.
Multilevel multiple imputation: An examination of competing
methods.
Degree: Psychology, 2015, Arizona State University
URL: http://repository.asu.edu/items/29655
► Missing data are common in psychology research and can lead to bias and reduced power if not properly handled. Multiple imputation is a state-of-the-art missing…
(more)
▼ Missing data are common in psychology research and can
lead to bias and reduced power if not properly handled. Multiple
imputation is a state-of-the-art missing data method recommended by
methodologists. Multiple imputation methods can generally be
divided into two broad categories: joint model (JM) imputation and
fully conditional specification (FCS) imputation. JM draws missing
values simultaneously for all incomplete variables using a
multivariate distribution (e.g., multivariate normal). FCS, on the
other hand, imputes variables one at a time, drawing missing values
from a series of univariate distributions. In the single-level
context, these two approaches have been shown to be equivalent with
multivariate normal data. However, less is known about the
similarities and differences of these two approaches with
multilevel data, and the methodological literature provides no
insight into the situations under which the approaches would
produce identical results. This document examined five multilevel
multiple imputation approaches (three JM methods and two FCS
methods) that have been proposed in the literature. An analytic
section shows that only two of the methods (one JM method and one
FCS method) used imputation models equivalent to a two-level joint
population model that contained random intercepts and different
associations across levels. The other three methods employed
imputation models that differed from the population model primarily
in their ability to preserve distinct level-1 and level-2
covariances. I verified the analytic work with computer
simulations, and the simulation results also showed that imputation
models that failed to preserve level-specific covariances produced
biased estimates. The studies also highlighted conditions that
exacerbated the amount of bias produced (e.g., bias was greater for
conditions with small cluster sizes). The analytic work and
simulations lead to a number of practical recommendations for
researchers.
Subjects/Keywords: Statistics; Psychology; Hierarchical; Missing Data; Multilevel Modeling; Multiple Imputation
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Mistler, S. A. (2015). Multilevel multiple imputation: An examination of competing
methods. (Doctoral Dissertation). Arizona State University. Retrieved from http://repository.asu.edu/items/29655
Chicago Manual of Style (16th Edition):
Mistler, Stephen Andrew. “Multilevel multiple imputation: An examination of competing
methods.” 2015. Doctoral Dissertation, Arizona State University. Accessed December 08, 2019.
http://repository.asu.edu/items/29655.
MLA Handbook (7th Edition):
Mistler, Stephen Andrew. “Multilevel multiple imputation: An examination of competing
methods.” 2015. Web. 08 Dec 2019.
Vancouver:
Mistler SA. Multilevel multiple imputation: An examination of competing
methods. [Internet] [Doctoral dissertation]. Arizona State University; 2015. [cited 2019 Dec 08].
Available from: http://repository.asu.edu/items/29655.
Council of Science Editors:
Mistler SA. Multilevel multiple imputation: An examination of competing
methods. [Doctoral Dissertation]. Arizona State University; 2015. Available from: http://repository.asu.edu/items/29655

University of Michigan
27.
Beesley, Lauren.
Missing Data and Variable Selection Methods for Cure Models in Cancer Research.
Degree: PhD, Biostatistics, 2018, University of Michigan
URL: http://hdl.handle.net/2027.42/144010
► In survival analysis, a common assumption is that all subjects will eventually experience the event of interest given long enough follow-up time. However, there are…
(more)
▼ In survival analysis, a common assumption is that all subjects will eventually experience the event of interest given long enough follow-up time. However, there are many settings in which this assumption does not hold. For example, suppose we are interested in studying cancer recurrence. If the treatment eradicated the cancer for some patients, then there will be a subset of the population that will never experience a recurrence. We call these subjects “cured.”
The Cox proportional hazards (CPH) mixture cure model and a generalization, the multistate cure model, can be used to model time-to-event outcomes in the cure setting. In this dissertation, we will address issues of missing data, variable selection, and parameter estimation for these models. We will also explore issues of missing covariate and outcome data for a more general class of models, of which cure models are a particular case.
In Chapter II, we propose several chained equations methods for imputing missing covariates under the CPH mixture cure model, and we compare the novel approaches with existing chained equations methods for imputing survival data without a cured fraction.
In Chapter III, we develop sequential
imputation methods for a general class of models with latent and partially latent variables (of which cure models are an example). In particular, we consider the setting where covariate/outcome missingness depends on the latent variable, which is a missing not at random mechanism.
In Chapter IV, we develop an EM algorithm for fitting the multistate cure model. The existing method for fitting this model requires custom software and can be slow to converge. In contrast, the proposed method can be easily implemented using standard software and typically converges quickly. We further propose a Monte Carlo EM algorithm for fitting the multistate cure model in the presence of covariate missingness and/or unequal censoring of the outcomes.
In Chapter V, we propose a generalization of the multistate cure model to incorporate subjects with persistent disease. This model has many parameters, and variable selection/shrinkage methods are needed to aid in estimation. We compare the performance of existing variable selection/shrinkage methods in estimating model parameters for a study of head and neck cancer.
In Chapter VI, we develop Bayesian methods for performing variable selection when we have order restrictions for model parameters. In particular, we consider the setting in which we have interactions with one or more order-restricted variables. A simulation study demonstrates promising properties of the proposed selection method.
Advisors/Committee Members: Taylor, Jeremy Michael George (committee member), Rozek, Laura Marie (committee member), Braun, Thomas M (committee member), Little, Roderick J (committee member), Schipper, Matthew Jason (committee member).
Subjects/Keywords: cure models; multiple imputation; cancer modeling; Public Health; Health Sciences
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Beesley, L. (2018). Missing Data and Variable Selection Methods for Cure Models in Cancer Research. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/144010
Chicago Manual of Style (16th Edition):
Beesley, Lauren. “Missing Data and Variable Selection Methods for Cure Models in Cancer Research.” 2018. Doctoral Dissertation, University of Michigan. Accessed December 08, 2019.
http://hdl.handle.net/2027.42/144010.
MLA Handbook (7th Edition):
Beesley, Lauren. “Missing Data and Variable Selection Methods for Cure Models in Cancer Research.” 2018. Web. 08 Dec 2019.
Vancouver:
Beesley L. Missing Data and Variable Selection Methods for Cure Models in Cancer Research. [Internet] [Doctoral dissertation]. University of Michigan; 2018. [cited 2019 Dec 08].
Available from: http://hdl.handle.net/2027.42/144010.
Council of Science Editors:
Beesley L. Missing Data and Variable Selection Methods for Cure Models in Cancer Research. [Doctoral Dissertation]. University of Michigan; 2018. Available from: http://hdl.handle.net/2027.42/144010
28.
Imbert, Alyssa.
Intégration de données hétérogènes complexes à partir de tableaux de tailles déséquilibrées : Integrating heterogeneous complex data from unbalanced datasets.
Degree: Docteur es, Mathématiques appliquées, 2018, Université Toulouse I – Capitole
URL: http://www.theses.fr/2018TOU10022
► Les avancées des nouvelles technologies de séquençage ont permis aux études cliniques de produire des données volumineuses et complexes. Cette complexité se décline selon diverses…
(more)
▼ Les avancées des nouvelles technologies de séquençage ont permis aux études cliniques de produire des données volumineuses et complexes. Cette complexité se décline selon diverses modalités, notamment la grande dimension, l’hétérogénéité des données au niveau biologique (acquises à différents niveaux de l’échelle du vivant et à divers moments de l’expérience), l’hétérogénéité du type de données, le bruit (hétérogénéité biologique ou données entachées d’erreurs) dans les données et la présence de données manquantes (au niveau d’une valeur ou d’un individu entier). L’intégration de différentes données est donc un défi important pour la biologie computationnelle. Cette thèse s’inscrit dans un projet de recherche clinique sur l’obésité, DiOGenes, pour lequel nous avons fait des propositions méthodologiques pour l’analyse et l’intégration de données. Ce projet est basé sur une intervention nutritionnelle menée dans huit pays européens et vise à analyser les effets de différents régimes sur le maintien pondéral et sur certains marqueurs de risque cardio-vasculaire et de diabète, chez des individus obèses. Dans le cadre de ce projet, mes travaux ont porté sur l’analyse de données transcriptomiques (RNA-Seq) avec des individus manquants et sur l’intégration de données transcriptomiques (nouvelle technique QuantSeq) avec des données cliniques. La première partie de cette thèse est consacrée aux données manquantes et à l’inférence de réseaux à partir de données d’expression RNA-Seq. Lors d’études longitudinales transcriptomiques, il arrive que certains individus ne soient pas observés à certains pas de temps, pour des raisons expérimentales. Nous proposons une méthode d’imputation multiple hot-deck (hd-MI) qui permet d’intégrer de l’information externe mesurée sur les mêmes individus et d’autres individus. hd-MI permet d’améliorer la qualité de l’inférence de réseau. La seconde partie porte sur une étude intégrative de données cliniques et transcriptomiques (mesurées par QuantSeq) basée sur une approche réseau. Nous y montrons l’intérêt de cette nouvelle technique pour l’acquisition de données transcriptomiques et l’analysons par une approche d’inférence de réseau en lien avec des données cliniques d’intérêt.
The development of high-throughput sequencing technologies has lead to a massive acquisition of high dimensional and complex datasets. Different features make these datasets hard to analyze : high dimensionality, heterogeneity at the biological level or at the data type level, the noise in data (due to biological heterogeneity or to errors in data) and the presence of missing data (for given values or for an entire individual). The integration of various data is thus an important challenge for computational biology. This thesis is part of a large clinical research project on obesity, DiOGenes, in which we have developed methods for data analysis and integration. The project is based on a dietary intervention that was led in eight Europeans centers. This study investigated the effect of macronutrient composition on…
Advisors/Committee Members: Villa-Vialaneix, Nathalie (thesis director), Viguerie, Nathalie (thesis director).
Subjects/Keywords: Analyse de données transcriptomiques; Imputation multiple hot-deck
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Imbert, A. (2018). Intégration de données hétérogènes complexes à partir de tableaux de tailles déséquilibrées : Integrating heterogeneous complex data from unbalanced datasets. (Doctoral Dissertation). Université Toulouse I – Capitole. Retrieved from http://www.theses.fr/2018TOU10022
Chicago Manual of Style (16th Edition):
Imbert, Alyssa. “Intégration de données hétérogènes complexes à partir de tableaux de tailles déséquilibrées : Integrating heterogeneous complex data from unbalanced datasets.” 2018. Doctoral Dissertation, Université Toulouse I – Capitole. Accessed December 08, 2019.
http://www.theses.fr/2018TOU10022.
MLA Handbook (7th Edition):
Imbert, Alyssa. “Intégration de données hétérogènes complexes à partir de tableaux de tailles déséquilibrées : Integrating heterogeneous complex data from unbalanced datasets.” 2018. Web. 08 Dec 2019.
Vancouver:
Imbert A. Intégration de données hétérogènes complexes à partir de tableaux de tailles déséquilibrées : Integrating heterogeneous complex data from unbalanced datasets. [Internet] [Doctoral dissertation]. Université Toulouse I – Capitole; 2018. [cited 2019 Dec 08].
Available from: http://www.theses.fr/2018TOU10022.
Council of Science Editors:
Imbert A. Intégration de données hétérogènes complexes à partir de tableaux de tailles déséquilibrées : Integrating heterogeneous complex data from unbalanced datasets. [Doctoral Dissertation]. Université Toulouse I – Capitole; 2018. Available from: http://www.theses.fr/2018TOU10022

University of Arizona
29.
Zhou, Muhan.
A Nearest-Neighbor Nonparametric Multiple Imputation Approach for Incomplete Categorical Data under Missing at Random
.
Degree: 2019, University of Arizona
URL: http://hdl.handle.net/10150/634211
► Incomplete categorical data is a common problem in medical research. If researchers simply use complete cases for data analysis, the estimation might be biased and/or…
(more)
▼ Incomplete categorical data is a common problem in medical research. If researchers simply use complete cases for data analysis, the estimation might be biased and/or inefficient due to ignoring the missing values. Under the assumption of missing at random (MAR), i.e. missing values depend only on the observed data but not on the unobserved data, an increasing number of approaches have been proposed to handle missing data. However, most of the existing missing-data methods for incomplete categorical data are either not robust or sensitive to extreme missingness probabilities. In my dissertation, I study a nearest-neighbor nonparametric
multiple imputation approach (NNMI) using two working models to impute values for a missing at random categorical variable, and to estimate marginal mean as well as conditional mean under three different study designs.
In the first paper, I adopt the NNMI for dealing with a categorical outcome with missing values and estimating the proportion of each category. Specifically, multinomial logistic regression/cumulative logistic regression is performed to construct a working model for predicting the incomplete categorical outcome. Logistic regression is performed to fit a working model for predicting the missingness probabilities. The predicted values from the two working models are used as scores for calculating distances between each missing value with other non-missing values. A weighting scheme is used to accommodate contributions from two working models when generating predictive scores. A missing value is imputed by randomly selecting one of the non-missing values with the smallest distances (donors) from each of the missing observations. I conduct a simulation study to evaluate the performance of the NNMI method and compare it with several alternative methods. A real-data application is presented using a dataset from the 2013 Behavioral Risk Factor Surveillance System (BRFSS) survey.
In the second paper, I use the NNMI method to handle missing covariate in logistic regression. Similarly, two working models are used to predict the incomplete covariate and the missingness probabilities. First, I perform a computation to assess the potential factors related to selecting an optimal size of donors. Second, the performance of the proposed method is compared with several alternative methods. Finally, the NNMI is applied on the 2013 BRFSS survey data to impute an incomplete categorical covariate and estimate the regression coefficients from a logistic regression model.
In the third paper, the NNMI is extended to handle missing covariate under a matched case-control study. The estimation is conducted using a conditional logistic regression model. The performance of the NNMI is compared with complete cases and six parametric
multiple imputation methods. The objective is to assess whether the NNMI demonstrates a doubly robust property compared with parametric methods. Then the NNMI is applied to impute an incomplete categorical covariate under a nested case-control cohort using the 2013 BRFSS…
Advisors/Committee Members: Hsu, Chiu-Hsieh (advisor), Bell, Melanie L. (committeemember), Guerra, Stefano (committeemember), Hu, Chengcheng (committeemember).
Subjects/Keywords: Categorical data;
Double Robustness;
Missing data;
Multiple imputation;
Nearest Neighbor
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zhou, M. (2019). A Nearest-Neighbor Nonparametric Multiple Imputation Approach for Incomplete Categorical Data under Missing at Random
. (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/634211
Chicago Manual of Style (16th Edition):
Zhou, Muhan. “A Nearest-Neighbor Nonparametric Multiple Imputation Approach for Incomplete Categorical Data under Missing at Random
.” 2019. Doctoral Dissertation, University of Arizona. Accessed December 08, 2019.
http://hdl.handle.net/10150/634211.
MLA Handbook (7th Edition):
Zhou, Muhan. “A Nearest-Neighbor Nonparametric Multiple Imputation Approach for Incomplete Categorical Data under Missing at Random
.” 2019. Web. 08 Dec 2019.
Vancouver:
Zhou M. A Nearest-Neighbor Nonparametric Multiple Imputation Approach for Incomplete Categorical Data under Missing at Random
. [Internet] [Doctoral dissertation]. University of Arizona; 2019. [cited 2019 Dec 08].
Available from: http://hdl.handle.net/10150/634211.
Council of Science Editors:
Zhou M. A Nearest-Neighbor Nonparametric Multiple Imputation Approach for Incomplete Categorical Data under Missing at Random
. [Doctoral Dissertation]. University of Arizona; 2019. Available from: http://hdl.handle.net/10150/634211

Duke University
30.
Si, Yajuan.
Nonparametric Bayesian Methods for Multiple Imputation of Large Scale Incomplete Categorical Data in Panel Studies
.
Degree: 2012, Duke University
URL: http://hdl.handle.net/10161/5837
► The thesis develops nonparametric Bayesian models to handle incomplete categorical variables in data sets with high dimension using the framework of multiple imputation. It…
(more)
▼ The thesis develops nonparametric Bayesian models to handle incomplete categorical variables in data sets with high dimension using the framework of
multiple imputation. It presents methods for ignorable missing data in cross-sectional studies, and potentially non-ignorable missing data in panel studies with refreshment samples. The first contribution is a fully Bayesian, joint modeling approach of
multiple imputation for categorical data based on Dirichlet process mixtures of multinomial distributions. The approach automatically models complex dependencies while being computationally expedient. I illustrate repeated sampling properties of the approach using simulated data. This approach offers better performance than default chained equations methods, which are often used in such settings. I apply the methodology to impute missing background data in the 2007 Trends in International Mathematics and Science Study. For the second contribution, I extend the nonparametric Bayesian
imputation engine to consider a mix of potentially non-ignorable attrition and ignorable item nonresponse in
multiple wave panel studies. Ignoring the attrition in models for panel data can result in biased inference if the reason for attrition is systematic and related to the missing values. Panel data alone cannot estimate the attrition effect without untestable assumptions about the missing data mechanism. Refreshment samples offer an extra data source that can be utilized to estimate the attrition effect while reducing reliance on strong assumptions of the missing data mechanism. I consider two novel Bayesian approaches to handle the attrition and item non-response simultaneously under
multiple imputation in a two wave panel with one refreshment sample when the variables involved are categorical and high dimensional. First, I present a semi-parametric selection model that includes an additive non-ignorable attrition model with main effects of all variables, including demographic variables and outcome measures in wave 1 and wave 2. The survey variables are modeled jointly using Bayesian mixture of multinomial distributions. I develop the posterior computation algorithms for the semi-parametric selection model under different prior choices for the regression coefficients in the attrition model. Second, I propose two Bayesian pattern mixture models for this scenario that use latent classes to model the dependency among the variables and the attrition. I develop a dependent Bayesian latent pattern mixture model for which variables are modeled via latent classes and attrition is treated as a covariate in the class allocation weights. And, I develop a joint Bayesian latent pattern mixture model, for which attrition and variables are modeled jointly via latent classes. I show via simulation studies that the pattern mixture models can recover true parameter estimates, even when inferences based on the panel alone are biased from attrition. I apply both the selection and pattern mixture…
Advisors/Committee Members: Reiter, Jerome P (advisor).
Subjects/Keywords: Statistics;
Categorical;
Large scale;
Multiple imputation;
Nonparametric Bayes;
Panel;
Refreshment sample
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APA (6th Edition):
Si, Y. (2012). Nonparametric Bayesian Methods for Multiple Imputation of Large Scale Incomplete Categorical Data in Panel Studies
. (Thesis). Duke University. Retrieved from http://hdl.handle.net/10161/5837
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Si, Yajuan. “Nonparametric Bayesian Methods for Multiple Imputation of Large Scale Incomplete Categorical Data in Panel Studies
.” 2012. Thesis, Duke University. Accessed December 08, 2019.
http://hdl.handle.net/10161/5837.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Si, Yajuan. “Nonparametric Bayesian Methods for Multiple Imputation of Large Scale Incomplete Categorical Data in Panel Studies
.” 2012. Web. 08 Dec 2019.
Vancouver:
Si Y. Nonparametric Bayesian Methods for Multiple Imputation of Large Scale Incomplete Categorical Data in Panel Studies
. [Internet] [Thesis]. Duke University; 2012. [cited 2019 Dec 08].
Available from: http://hdl.handle.net/10161/5837.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Si Y. Nonparametric Bayesian Methods for Multiple Imputation of Large Scale Incomplete Categorical Data in Panel Studies
. [Thesis]. Duke University; 2012. Available from: http://hdl.handle.net/10161/5837
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
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