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Rutgers University
1.
Fan, Yi, 1990-.
New nonparametric approaches for multivariate and functional data analysis in outlier detection, construction of tolerance tubes, and clustering.
Degree: PhD, Statistics and Biostatistics, 2016, Rutgers University
URL: https://rucore.libraries.rutgers.edu/rutgers-lib/49960/ 
► Recent advances of powerful computing and data acquisition technologies have made large complex datasets ever-present, including high-dimensional or functional data. Most existing statistical approaches for…
(more)
▼ Recent advances of powerful computing and data acquisition technologies have made large complex datasets ever-present, including high-dimensional or functional data. Most existing statistical approaches for multivariate or functional data rely on parametric assumptions such as normality. In reality, such assumptions are either difficult to justify or verify. The goal of this dissertation is to develop general nonparametric statistical approaches for outlier detection, tolerance tubes construction, and clustering for multivariate and functional data. i) In Chapter 3, we propose a general approach named Antipodal Reflection Depth (ARD), to refine any existing function of depth (henceforth base depth) to form a class of new depth functions. ARD has the advantage over its base depth in capturing the relative magnitude of deviation from all data points to the deepest one. This desirable property is key in making ARD particularly useful in many applications. Here, we focus primarily on its utility in outlier detection. ii) In Chapter 4, we introduce tolerance tubes, which can be viewed as generalizations of tolerance intervals/regions to functional settings. A tolerance tube ensures a specified portion of the functional dataset be contained within the tolerance limits with some level of confidence. In addition to extending the commonly accepted definitions of β-content and β-expectation, we introduce modifications by incorporating an exempt level α. The latter relaxes the definitions by allowing α portion of each functional to be exempt from the requirements and is thus particularly useful to offset allowable occasional aberrations. iii) In Chapter 5, we propose a new clustering approach named K-means on Pairwise Distance (KMPD), and show it to be effective in detecting clusters with different sizes. Moreover, KMPD has the capability of grouping anomalous sample points into a single cluster, and therefore is an effective approach for outlier detection as well. All these approaches are completely non-parametric and data-driven, and thus can be broadly applicable. Relevant theoretical properties are investigated and justified. These approaches are also illustrated and tested using data from both simulations and a real application on a medical study of continuous glucose monitoring.
Advisors/Committee Members: Liu, Regina (chair), Zhang, Cun-Hui (internal member), Xie, Minge (internal member), Cheng, Andrew (outside member).
Subjects/Keywords: Outliers (Statistics)
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APA (6th Edition):
Fan, Yi, 1. (2016). New nonparametric approaches for multivariate and functional data analysis in outlier detection, construction of tolerance tubes, and clustering. (Doctoral Dissertation). Rutgers University. Retrieved from https://rucore.libraries.rutgers.edu/rutgers-lib/49960/
Chicago Manual of Style (16th Edition):
Fan, Yi, 1990-. “New nonparametric approaches for multivariate and functional data analysis in outlier detection, construction of tolerance tubes, and clustering.” 2016. Doctoral Dissertation, Rutgers University. Accessed March 05, 2021.
https://rucore.libraries.rutgers.edu/rutgers-lib/49960/.
MLA Handbook (7th Edition):
Fan, Yi, 1990-. “New nonparametric approaches for multivariate and functional data analysis in outlier detection, construction of tolerance tubes, and clustering.” 2016. Web. 05 Mar 2021.
Vancouver:
Fan, Yi 1. New nonparametric approaches for multivariate and functional data analysis in outlier detection, construction of tolerance tubes, and clustering. [Internet] [Doctoral dissertation]. Rutgers University; 2016. [cited 2021 Mar 05].
Available from: https://rucore.libraries.rutgers.edu/rutgers-lib/49960/.
Council of Science Editors:
Fan, Yi 1. New nonparametric approaches for multivariate and functional data analysis in outlier detection, construction of tolerance tubes, and clustering. [Doctoral Dissertation]. Rutgers University; 2016. Available from: https://rucore.libraries.rutgers.edu/rutgers-lib/49960/
University of Alberta
2.
Babakhani, Mahshid.
Geostatistical Modeling in Presence of Extreme
Values.
Degree: MS, Department of Civil and Environmental
Engineering, 2014, University of Alberta
URL: https://era.library.ualberta.ca/files/tx31qj23c
► Geostatistical modeling in presence of extreme values needs special attention. Certain extreme high values known as outliers require proper treatment or mineral resources may be…
(more)
▼ Geostatistical modeling in presence of extreme values
needs special attention. Certain extreme high values known as
outliers require proper treatment or mineral resources may be
overstated. A number of methodologies are proposed in this thesis
to identify and manage outliers. The main goal of the outlier
management strategies is to keep the outliers but control their
influence on local block estimates, if required, by reducing their
values. The variogram is an essential geostatistical tool that is
highly sensitive to outlier high values. There are alternatives to
the experimental traditional variogram. The pairwise relative
variogram is known to be a very robust alternative to the
experimental traditional variogram in presence of outlier high
values. There are two issues with the pairwise relative variogram;
(1) an unknown sill, and (2) its convergence to the wrong
variogram. Solutions to both of these problems are developed and
documented in this thesis. Another contribution of this thesis is a
simulation-based approach for cutting outlier values. The volume of
influence of an outlier is identified. The uncertainty in the mean
of the volume of influence is established by simulation. Then, the
outlier value is reduced until the estimated quantity of metal
within the identified volume is reasonable relative to the
distribution coming from simulation. The outlier management
strategies presented in this thesis will provide practical
assistance for geological modeling for engineering
evaluations.
Subjects/Keywords: Outliers; Geostatistical Modeling; Extreme values
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APA (6th Edition):
Babakhani, M. (2014). Geostatistical Modeling in Presence of Extreme
Values. (Masters Thesis). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/tx31qj23c
Chicago Manual of Style (16th Edition):
Babakhani, Mahshid. “Geostatistical Modeling in Presence of Extreme
Values.” 2014. Masters Thesis, University of Alberta. Accessed March 05, 2021.
https://era.library.ualberta.ca/files/tx31qj23c.
MLA Handbook (7th Edition):
Babakhani, Mahshid. “Geostatistical Modeling in Presence of Extreme
Values.” 2014. Web. 05 Mar 2021.
Vancouver:
Babakhani M. Geostatistical Modeling in Presence of Extreme
Values. [Internet] [Masters thesis]. University of Alberta; 2014. [cited 2021 Mar 05].
Available from: https://era.library.ualberta.ca/files/tx31qj23c.
Council of Science Editors:
Babakhani M. Geostatistical Modeling in Presence of Extreme
Values. [Masters Thesis]. University of Alberta; 2014. Available from: https://era.library.ualberta.ca/files/tx31qj23c
North Carolina State University
3.
Schumann, David Heinz.
Robust Variable Selection.
Degree: PhD, Statistics, 2009, North Carolina State University
URL: http://www.lib.ncsu.edu/resolver/1840.16/4764
► The prevalence of extreme outliers in many regression data sets has led to the development of robust methods that can handle these observations. While much…
(more)
▼ The prevalence of extreme
outliers in many regression data sets has led to the development of robust methods that can handle these observations. While much attention has been placed on the problem of estimating regression coefficients in the presence of
outliers, few methods address variable selection. We develop and study robust versions of the forward selection algorithm, one of the most popular standard variable selection techniques. Specifically we modify the VAMS procedure, a version of forward selection tuned to control the false selection rate, to simultaneously select variables and eliminate
outliers. In an alternative approach, robust versions of the forward selection algorithm are developed using the robust forward addition sequence associated with the generalized score statistic. Combining the robust forward addition sequence with robust versions of BIC and the VAMS procedure, a final model is obtained. Monte Carlo simulation compares these robust methods to current robust methods like the LSA and LAD-LASSO. Further simulation investigates the relationship between the breakdown point of the estimation methods central to each procedure and the breakdown point of the final variable selection method.
Advisors/Committee Members: Dennis Boos, Committee Member (advisor), Judy Wang, Committee Member (advisor), Leonard Stefanski, Committee Co-Chair (advisor), Lexin Li, Committee Member (advisor).
Subjects/Keywords: VAMS; outliers; variable selection; robust
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APA (6th Edition):
Schumann, D. H. (2009). Robust Variable Selection. (Doctoral Dissertation). North Carolina State University. Retrieved from http://www.lib.ncsu.edu/resolver/1840.16/4764
Chicago Manual of Style (16th Edition):
Schumann, David Heinz. “Robust Variable Selection.” 2009. Doctoral Dissertation, North Carolina State University. Accessed March 05, 2021.
http://www.lib.ncsu.edu/resolver/1840.16/4764.
MLA Handbook (7th Edition):
Schumann, David Heinz. “Robust Variable Selection.” 2009. Web. 05 Mar 2021.
Vancouver:
Schumann DH. Robust Variable Selection. [Internet] [Doctoral dissertation]. North Carolina State University; 2009. [cited 2021 Mar 05].
Available from: http://www.lib.ncsu.edu/resolver/1840.16/4764.
Council of Science Editors:
Schumann DH. Robust Variable Selection. [Doctoral Dissertation]. North Carolina State University; 2009. Available from: http://www.lib.ncsu.edu/resolver/1840.16/4764
Northeastern University
4.
Zhang, Yuexi.
Outliers cleaning in dynamic systems.
Degree: MS, Department of Electrical and Computer Engineering, 2017, Northeastern University
URL: http://hdl.handle.net/2047/D20292552
► In this thesis, we focused on solving the problem of detecting and cleaning outliers when estimating human poses in a temporal sequence. We addressed this…
(more)
▼ In this thesis, we focused on solving the problem of detecting and cleaning outliers when estimating human poses in a temporal sequence. We addressed this challenge by formulating optimization problems that use properties of dynamic systems explaining the temporal data. In particular, we solved this problem using two different approaches. In the first approach, we assumed that the data was generated by an underlying, but unknown, dynamic system. So, we designed a framework which combined a distance-like function of the Hankel matrix constructed by measurements to detect sharp changes with a data Interpolation algorithm. In the second approach, we also incorporated apriori knowledge of the underlying dynamics. In this case, it was assumed that training data is available to learn the underlying dynamics. Then, trajectories were cleaned while respecting this apriori knowledge. We tested the proposed approaches using both synthetic and real data from video sequences. Experiments showed that our approaches had better performances.
Subjects/Keywords: outliers; dynamic systems; human poses
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APA (6th Edition):
Zhang, Y. (2017). Outliers cleaning in dynamic systems. (Masters Thesis). Northeastern University. Retrieved from http://hdl.handle.net/2047/D20292552
Chicago Manual of Style (16th Edition):
Zhang, Yuexi. “Outliers cleaning in dynamic systems.” 2017. Masters Thesis, Northeastern University. Accessed March 05, 2021.
http://hdl.handle.net/2047/D20292552.
MLA Handbook (7th Edition):
Zhang, Yuexi. “Outliers cleaning in dynamic systems.” 2017. Web. 05 Mar 2021.
Vancouver:
Zhang Y. Outliers cleaning in dynamic systems. [Internet] [Masters thesis]. Northeastern University; 2017. [cited 2021 Mar 05].
Available from: http://hdl.handle.net/2047/D20292552.
Council of Science Editors:
Zhang Y. Outliers cleaning in dynamic systems. [Masters Thesis]. Northeastern University; 2017. Available from: http://hdl.handle.net/2047/D20292552
University of Notre Dame
5.
Jiyun Zu.
Robust Procedures for Mediation Analysis</h1>.
Degree: Psychology, 2009, University of Notre Dame
URL: https://curate.nd.edu/show/x059c53710k
► Mediation analysis investigates how certain variables mediate the effect of predictors on outcome variables. Existing studies of mediation have been limited to normal theory…
(more)
▼ Mediation analysis investigates how certain
variables mediate the effect of predictors on outcome variables.
Existing studies of mediation have been limited to normal theory
maximum likelihood (ML) or least squares with normally distributed
data. Because real data in psychology are seldom normally
distributed, classic methods often lead to biased or inefficient
parameter estimates, which make the result of mediation analysis
misleading. To circumvent these problems, this dissertation
proposes to utilize robust methods for parameter estimation, and
then to evaluate the mediated effect based on robust estimates.
Theoretical details of robust procedures for mediation analysis are
provided. Their properties are investigated via simulation studies,
and results suggest that (a) the most commonly used Sobel z method
relying on ML point and information-based standard error (SE)
estimates has the worst overall performance; (b) the distribution
of the product confidence interval based on robust point and
sandwich-type SE estimates has the best overall performance.
Applications of robust procedures are illustrated using real data
examples, which show that robust procedures provide more reliable
results.
Advisors/Committee Members: Ke-Hai Yuan , Committee Member.
Subjects/Keywords: outliers; nonnormality
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APA (6th Edition):
Zu, J. (2009). Robust Procedures for Mediation Analysis</h1>. (Thesis). University of Notre Dame. Retrieved from https://curate.nd.edu/show/x059c53710k
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):
Zu, Jiyun. “Robust Procedures for Mediation Analysis</h1>.” 2009. Thesis, University of Notre Dame. Accessed March 05, 2021.
https://curate.nd.edu/show/x059c53710k.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Zu, Jiyun. “Robust Procedures for Mediation Analysis</h1>.” 2009. Web. 05 Mar 2021.
Vancouver:
Zu J. Robust Procedures for Mediation Analysis</h1>. [Internet] [Thesis]. University of Notre Dame; 2009. [cited 2021 Mar 05].
Available from: https://curate.nd.edu/show/x059c53710k.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Zu J. Robust Procedures for Mediation Analysis</h1>. [Thesis]. University of Notre Dame; 2009. Available from: https://curate.nd.edu/show/x059c53710k
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Illinois – Urbana-Champaign
6.
Zwilling, Christopher Eric.
New approaches for outlier detection.
Degree: PhD, Psychology, 2016, University of Illinois – Urbana-Champaign
URL: http://hdl.handle.net/2142/97645
► Outlier detection has relevance in many modern day contexts, including health care, engineering, data processing and analysis, credit card fraud, monitoring computer and internet intrusions…
(more)
▼ Outlier detection has relevance in many modern day contexts, including health care, engineering, data processing and analysis, credit card fraud, monitoring computer and internet intrusions and wearable personal health sensors. Outlier detection once represented a single pre-processing step, completed prior to the analysis of data proper. Today it has importance in all stages of the data analysis pipeline, from initial processing to defining data points of interest, such as when a sensor detects an anomaly. Moreover, as data sets have grown to encompass millions and billions of observations and variables, it is imperative to have outlier detection methods capable of effectively and automatically winnowing through large amounts of data with few or no inputs from a data analyst. Many existing outlier detection methods are constrained in certain ways which might limit their utility and efficacy. For instance, it is not uncommon for outlier detection methods to require some knowledge about the data under study or require the analyst to specify information about the number of
outliers in the data. Another possible constraint of many outlier detection methods is the use of the raw data. Sometimes
outliers can readily be detected in the raw data; but sometimes not, in which case one can achieve greater sensitivity and accuracy from features derived from data. This study uses feature extraction on multivariate time series data and demonstrates the efficacy of a set of features and their potential for aggregation through the use of Voronoi diagrams. Voronoi diagrams are constructed from the data to create tessellations which satisfy certain geometric properties. The covariance based outlier detection is proposed and demonstrated to addresses both of these challenges. It utilizes covariance information in the data and its efficacy lies in its ability to take a set of features constructed from the data and determine which feature is best at detecting
outliers. The method is shown to work effectively on time series data; but it is general and can be applied or extended to other types of data objects and data sets.
Advisors/Committee Members: Wang, Michelle Y. (advisor), Wang, Michelle Y. (Committee Chair), Anderson, Carolyn (committee member), Kohn, Hans-Friedrich (committee member), Marden, John (committee member), Drasgow, Fritz (committee member).
Subjects/Keywords: Outliers; Covariance; Time series
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APA ·
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Manager
APA (6th Edition):
Zwilling, C. E. (2016). New approaches for outlier detection. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/97645
Chicago Manual of Style (16th Edition):
Zwilling, Christopher Eric. “New approaches for outlier detection.” 2016. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed March 05, 2021.
http://hdl.handle.net/2142/97645.
MLA Handbook (7th Edition):
Zwilling, Christopher Eric. “New approaches for outlier detection.” 2016. Web. 05 Mar 2021.
Vancouver:
Zwilling CE. New approaches for outlier detection. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2016. [cited 2021 Mar 05].
Available from: http://hdl.handle.net/2142/97645.
Council of Science Editors:
Zwilling CE. New approaches for outlier detection. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2016. Available from: http://hdl.handle.net/2142/97645
University of Georgia
7.
Wang, Jue.
The sensitivity of hierarchical linear models to outliers.
Degree: 2015, University of Georgia
URL: http://hdl.handle.net/10724/31334
► The hierarchical linear model (HLM) has become popular in behavioral research, and has been widely used in various educational studies in recent years. Violations of…
(more)
▼ The hierarchical linear model (HLM) has become popular in behavioral research, and has been widely used in various educational studies in recent years. Violations of model assumptions can have a non-ignorable impact on the model. One issue
in this regard is the sensitivity of HLM to outliers. The purpose of this study is to evaluate the sensitivity of two-level HLM to the outliers by exploring the influence of outliers on parameter estimates of HLM under normality assumptions at both
levels. A simulation study is performed to examine the biases of parameter estimates with different numbers and types of outliers (3 SD and 5 SD) given different sample sizes. Results indicated that the biases of parameter estimates increased with the
growing of standard deviation and the number of outliers. The estimates have very small biases with a few outliers. A robust method Huber sandwich estimator corrects the standard errors efficiently when there is a large proportion of
outliers.
Subjects/Keywords: Hierarchical linear model; outliers; sensitivity
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APA (6th Edition):
Wang, J. (2015). The sensitivity of hierarchical linear models to outliers. (Thesis). University of Georgia. Retrieved from http://hdl.handle.net/10724/31334
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):
Wang, Jue. “The sensitivity of hierarchical linear models to outliers.” 2015. Thesis, University of Georgia. Accessed March 05, 2021.
http://hdl.handle.net/10724/31334.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Wang, Jue. “The sensitivity of hierarchical linear models to outliers.” 2015. Web. 05 Mar 2021.
Vancouver:
Wang J. The sensitivity of hierarchical linear models to outliers. [Internet] [Thesis]. University of Georgia; 2015. [cited 2021 Mar 05].
Available from: http://hdl.handle.net/10724/31334.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Wang J. The sensitivity of hierarchical linear models to outliers. [Thesis]. University of Georgia; 2015. Available from: http://hdl.handle.net/10724/31334
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Oklahoma
8.
Sadik, Shiblee.
Online Detection of Outliers for Data Streams.
Degree: PhD, 2013, University of Oklahoma
URL: http://hdl.handle.net/11244/320199
► Extensive theoretical and empirical analyses have been conducted to evaluate the performance of Orion and Wadjet using real and synthetic datasets. The evaluation results show…
(more)
▼ Extensive theoretical and empirical analyses have been conducted to evaluate the performance of Orion and Wadjet using real and synthetic datasets. The evaluation results show that both algorithms have better accuracy and execution time than the state-of-art techniques when applied to homogeneous data stream applications. The results also show that Wadjet is effective in detecting
outliers in heterogeneous data streams which cannot be handled by existing algorithms.
Advisors/Committee Members: Gruenwald, Le (advisor).
Subjects/Keywords: Outliers (Statistics); Algorithms; Data mining
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APA (6th Edition):
Sadik, S. (2013). Online Detection of Outliers for Data Streams. (Doctoral Dissertation). University of Oklahoma. Retrieved from http://hdl.handle.net/11244/320199
Chicago Manual of Style (16th Edition):
Sadik, Shiblee. “Online Detection of Outliers for Data Streams.” 2013. Doctoral Dissertation, University of Oklahoma. Accessed March 05, 2021.
http://hdl.handle.net/11244/320199.
MLA Handbook (7th Edition):
Sadik, Shiblee. “Online Detection of Outliers for Data Streams.” 2013. Web. 05 Mar 2021.
Vancouver:
Sadik S. Online Detection of Outliers for Data Streams. [Internet] [Doctoral dissertation]. University of Oklahoma; 2013. [cited 2021 Mar 05].
Available from: http://hdl.handle.net/11244/320199.
Council of Science Editors:
Sadik S. Online Detection of Outliers for Data Streams. [Doctoral Dissertation]. University of Oklahoma; 2013. Available from: http://hdl.handle.net/11244/320199
Rutgers University
9.
Xia, Yi, 1975-.
Extended bootlier procedure for detection of outliers in univariate samples and linear regression analysis.
Degree: PhD, Statistics and Biostatistics, 2014, Rutgers University
URL: https://rucore.libraries.rutgers.edu/rutgers-lib/45566/
► Determining if a dataset has one or more outliers is a fundamental and challenging problem in statistical analysis. This dissertation introduces a statistical framework that…
(more)
▼ Determining if a dataset has one or more outliers is a fundamental and challenging problem in statistical analysis. This dissertation introduces a statistical framework that addresses two well-known problems in the outlier analysis. The first problem (Problem 1) is to detect outliers in independent and identically distributed univariate samples, which is the basic setting of outlier problem. The second problem (Problem 2) is to detect outliers and influential observations in the linear regression analysis, which is a major topic in linear regression model diagnostics and represents a more complete setting. The proposed framework is motivated by a graphic outlier detection method proposed recently for Problem 1. It is observed in bootstrapping that some bootstrap samples contain outliers while others do not, when outliers are present in a sample. Based on this observation, the method discovers that a bootstrap sample statistic (termed “mean – trimmed mean”) is sensitive to outliers, and particularly its histogram is multimodal in the presence of outliers. Consequently outliers are detected by plotting and visually checking the histogram. Considering that method captures the essence of outliers that the researches often call, the proposed framework further develops it to a complete inference procedure by constructing a formal statistical test based on a quantitative index that measures the degree of outliers effect. The proposed framework is first developed to address Problem 1. A procedure with a formal test is detailed and the large sample theory is developed to support the proposed procedure. Then, the procedure is extended to linear regression to address Problem 2. The measures for outliers and influential observations, including several residuals and a square-root version of Cook’s distance, are discussed, and large sample theory is developed for such non-independent case. In addressing both problems, the simulation studies are conducted and real data examples are explored to show the wide-range application of the proposed framework. In particular, the comparison with other commonly used methods in the simulation studies demonstrates the overall advantage of the proposed framework.
Advisors/Committee Members: Xie, Minge (chair), Kolassa, John (internal member), Dicker, Lee (internal member), Li, Dayong (outside member).
Subjects/Keywords: Outliers (Statistics); Regression analysis
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APA ·
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Manager
APA (6th Edition):
Xia, Yi, 1. (2014). Extended bootlier procedure for detection of outliers in univariate samples and linear regression analysis. (Doctoral Dissertation). Rutgers University. Retrieved from https://rucore.libraries.rutgers.edu/rutgers-lib/45566/
Chicago Manual of Style (16th Edition):
Xia, Yi, 1975-. “Extended bootlier procedure for detection of outliers in univariate samples and linear regression analysis.” 2014. Doctoral Dissertation, Rutgers University. Accessed March 05, 2021.
https://rucore.libraries.rutgers.edu/rutgers-lib/45566/.
MLA Handbook (7th Edition):
Xia, Yi, 1975-. “Extended bootlier procedure for detection of outliers in univariate samples and linear regression analysis.” 2014. Web. 05 Mar 2021.
Vancouver:
Xia, Yi 1. Extended bootlier procedure for detection of outliers in univariate samples and linear regression analysis. [Internet] [Doctoral dissertation]. Rutgers University; 2014. [cited 2021 Mar 05].
Available from: https://rucore.libraries.rutgers.edu/rutgers-lib/45566/.
Council of Science Editors:
Xia, Yi 1. Extended bootlier procedure for detection of outliers in univariate samples and linear regression analysis. [Doctoral Dissertation]. Rutgers University; 2014. Available from: https://rucore.libraries.rutgers.edu/rutgers-lib/45566/
Universidade Federal de Viçosa
10.
Alyne Neves Silva.
Detecção de Outliers em Séries Espaço-Temporais: Análise de Precipitação em Minas Gerais.
Degree: 2012, Universidade Federal de Viçosa
URL: http://www.tede.ufv.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=5058
► Séries temporais são algumas vezes influenciadas por interrupções de eventos, tais como greves, eclosão de guerras, entre outras. Estas interrupções originam observações atípicas ou outliers…
(more)
▼ Séries temporais são algumas vezes influenciadas por interrupções de eventos, tais como greves, eclosão de guerras, entre outras. Estas interrupções originam observações atípicas ou outliers que influenciam diretamente na homogeneidade da série, ocasionando interpretações e inferências errôneas da variável sob estudo, sendo muito comum em dados climatológicos. Assim, com o interesse de detectar outliers em séries temporais de precipitação, o presente trabalho teve por objetivo estabelecer um método de detecção outliers. Para tal, realizou-se a junção da modelagem ARIMA e de uma das metodologias clássicas de geoestatística, a autovalidação. O critério proposto compara os resíduos da análise de séries temporais com intervalos de confiança dos resíduos da autovalidação. Foram analisadas séries temporais da precipitação média mensal por dias chuvosos de 43 estações pluviométricas localizadas no estado de Minas Gerais, entre os anos de 2000 a 2005. Os procedimentos de análise vão da descrição da periodicidade por meio do periodograma até a obtenção da autovalidação, à partir da estimação dos modelos de semivariograma pelos métodos de mínimos quadrados ordinários e máxima verossimilhança. Pelos resultados, para o período sob estudo, foram detectado 165 outliers, espalhados entre as 43 estações pluviométricas. A estação Fazenda Campo Grande, localizada no município de Passa Tempo, foi a estação em que se registrou o maior número de outliers, 45 no total. Conforme os resultados obtidos considerou-se o método proposto muito eficiente na detecção de outliers e, consequentemente, na análise da homogeneidade das observações.
Time series are sometimes influenced by disruptions of events, such as strikes, the outbreak of war, among others. These interrupts originate atypical observations or outliers that directly influence the homogeneity of the series, leading to erroneous inferences and interpretations of the variable under study, being very common in climatological data. So, in the interest of detecting outliers in time series of precipitation, this study aimed to establish a method of detecting outliers. For this, there was the junction of ARIMA models and methodologies of the classical geostatistics, the self-validation. The proposed criterion compares waste of time series analysis with confidence intervals of the residue of self-validation. We analyzed time series of average monthly rainfall for rainy days of 43 rainfall stations in the state of Minas Gerais, between the years 2000 to 2005. The analysis procedures ranging from the description of the periodicity through the periodogram to obtain validation, from the estimation of the semivariogram models by ordinary least squares methods and maximum likelihood. The results for the period under study, 165 were detected outliers, spread between the 43 rainfall stations. The station Campo Grande Ranch, located in the municipality of Passa Tempo, was the season in which they recorded the highest number of outliers, 45 in total. As the results, we considered the proposed method…
Advisors/Committee Members: Gérson Rodrigues dos Santos, Fernando Falco Pruski, Silvio Bueno Pereira, Eric Batista Ferreira, Nerilson Terra Santos.
Subjects/Keywords: CIENCIAS AGRARIAS; Inconsistências; ARIMA; Autovalidação; Outliers; Inconsistencies; ARIMA; self-validation; Outliers
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APA (6th Edition):
Silva, A. N. (2012). Detecção de Outliers em Séries Espaço-Temporais: Análise de Precipitação em Minas Gerais. (Thesis). Universidade Federal de Viçosa. Retrieved from http://www.tede.ufv.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=5058
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):
Silva, Alyne Neves. “Detecção de Outliers em Séries Espaço-Temporais: Análise de Precipitação em Minas Gerais.” 2012. Thesis, Universidade Federal de Viçosa. Accessed March 05, 2021.
http://www.tede.ufv.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=5058.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Silva, Alyne Neves. “Detecção de Outliers em Séries Espaço-Temporais: Análise de Precipitação em Minas Gerais.” 2012. Web. 05 Mar 2021.
Vancouver:
Silva AN. Detecção de Outliers em Séries Espaço-Temporais: Análise de Precipitação em Minas Gerais. [Internet] [Thesis]. Universidade Federal de Viçosa; 2012. [cited 2021 Mar 05].
Available from: http://www.tede.ufv.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=5058.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Silva AN. Detecção de Outliers em Séries Espaço-Temporais: Análise de Precipitação em Minas Gerais. [Thesis]. Universidade Federal de Viçosa; 2012. Available from: http://www.tede.ufv.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=5058
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
11.
Hacini, Akram.
Une approche de détection d'outliers en présence de l'incertitude : An outlier detection approach in the presence of uncertainty.
Degree: Docteur es, Informatique, 2018, Paris 8
URL: http://www.theses.fr/2018PA080068
► Un des aspects de complexité des nouvelles données, issues des différents systèmes de traitement,sont l’imprécision, l’incertitude, et l’incomplétude. Ces aspects ont aggravés la multiplicité etdissémination…
(more)
▼ Un des aspects de complexité des nouvelles données, issues des différents systèmes de traitement,sont l’imprécision, l’incertitude, et l’incomplétude. Ces aspects ont aggravés la multiplicité etdissémination des sources productrices de données, qu’on observe facilement dans les systèmesde contrôle et de monitoring. Si les outils de la fouille de données sont devenus assez performants avec des données dont on dispose de connaissances a priori fiables, ils ne peuvent pas êtreappliqués aux données où les connaissances elles mêmes peuvent être entachées d’incertitude etd’imprécision. De ce fait, de nouvelles approches qui prennent en compte cet aspect vont certainement améliorer les performances des systèmes de fouille de données, dont la détection desoutliers, objet de notre recherche dans le cadre de cette thèse. Cette thèse s’inscrit dans cette optique, à savoir la proposition d’une nouvelle méthode pourla détection d’outliers dans les données incertaines et/ou imprécises. En effet, l’imprécision etl’incertitude des expertises relatives aux données d’apprentissage, est un aspect de complexitédes données. Pour pallier à ce problème particulier d’imprécision et d’incertitude des donnéesexpertisées, nous avons combinés des techniques issues de l’apprentissage automatique, et plusparticulièrement le clustering, et des techniques issues de la logique floue, en particulier les ensembles flous, et ce, pour pouvoir projeter de nouvelles observations, sur les clusters des donnéesd’apprentissage, et après seuillage, pouvoir définir les observations à considérer comme aberrantes(outliers) dans le jeu de données considéré.Concrètement, en utilisant les tables de décision ambigües (TDA), nous sommes partis des indices d’ambigüité des données d’apprentissage pour calculer les indices d’ambigüités des nouvellesobservations (données de test), et ce en faisant recours à l’inférence floue. Après un clustering del’ensemble des indices d’ambigüité, une opération α-coupe, nous a permis de définir une frontièrede décision au sein des clusters, et qui a été utilisée à son tour pour catégoriser les observations,en normales (inliers) ou aberrantes (outliers). La force de la méthode proposée réside dans sonpouvoir à traiter avec des données d’apprentissage imprécises et/ou incertaines en utilisant uniquement les indices d’ambigüité, palliant ainsi aux différents problèmes d’incomplétude des jeuxde données. Les métriques de faux positifs et de rappel, nous ont permis d’une part d’évaluer lesperformances de notre méthode, et aussi de la paramétrer selon les choix de l’utilisateur.
One of the complexity aspects of the new data produced by the different processing systems is the inaccuracy, the uncertainty, and the incompleteness. These aspects are aggravated by the multiplicity and the dissemination of data-generating sources, that can be easily observed within various control and monitoring systems. While the tools of data mining have become fairly efficient with data that have reliable prior knowledge, they cannot be applied to data where…
Advisors/Committee Members: Akdag, Herman (thesis director).
Subjects/Keywords: La detection des outliers; Outliers et logique floue; La detection des outliers sous incertitude; Anomalies; Données bruitées
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Hacini, A. (2018). Une approche de détection d'outliers en présence de l'incertitude : An outlier detection approach in the presence of uncertainty. (Doctoral Dissertation). Paris 8. Retrieved from http://www.theses.fr/2018PA080068
Chicago Manual of Style (16th Edition):
Hacini, Akram. “Une approche de détection d'outliers en présence de l'incertitude : An outlier detection approach in the presence of uncertainty.” 2018. Doctoral Dissertation, Paris 8. Accessed March 05, 2021.
http://www.theses.fr/2018PA080068.
MLA Handbook (7th Edition):
Hacini, Akram. “Une approche de détection d'outliers en présence de l'incertitude : An outlier detection approach in the presence of uncertainty.” 2018. Web. 05 Mar 2021.
Vancouver:
Hacini A. Une approche de détection d'outliers en présence de l'incertitude : An outlier detection approach in the presence of uncertainty. [Internet] [Doctoral dissertation]. Paris 8; 2018. [cited 2021 Mar 05].
Available from: http://www.theses.fr/2018PA080068.
Council of Science Editors:
Hacini A. Une approche de détection d'outliers en présence de l'incertitude : An outlier detection approach in the presence of uncertainty. [Doctoral Dissertation]. Paris 8; 2018. Available from: http://www.theses.fr/2018PA080068
12.
William Pereira Marciano, Francisco.
Modelo de calibração com erros simétricos
.
Degree: 2012, Universidade Federal de Pernambuco
URL: http://repositorio.ufpe.br/handle/123456789/6639
► Neste trabalho e considerado o problema de calibrac~ao linear simetrico. A maioria dos modelos de calibrac~ao presentes na literatura sup~oe que os erros s~ao normalmente…
(more)
▼ Neste trabalho e considerado o problema de calibrac~ao linear simetrico. A maioria dos
modelos de calibrac~ao presentes na literatura sup~oe que os erros s~ao normalmente distribu
idos, no entanto, a distribuic~ao normal e extremamente sensivel a presenca de observa
c~oes atipicas. O uso de distribuic~oes de caudas pesadas da classe de distribuic~oes
simetricas pode ser uma soluc~ao a este tipo de problema. Distribuic~oes alternativas pertencentes
a classe simetrica de distribuic~oes como suposic~ao para os erros do modelo de
calibrac~ao linear com repetic~oes na variavel resposta s~ao propostas neste trabalho, alem da
distribuic~ao normal, estudamos as distribuic~oes t-Student, exponencial pot^encia e logistica
tipo II. A metodologia de maxima verossimilhanca e empregada para obter as estimativas
dos par^ametros para cada um dos modelos em estudo. Realizamos estudos de simulac~ao
para verificar o comportamento assintotico dos estimadores dos par^ametros para cada um
dos modelos. Finalmente apresentamos aplicac~oes dos modelos propostos a conjuntos de
dados reais
Advisors/Committee Members: José de Azevedo Cysneiros, Francisco (advisor).
Subjects/Keywords: Modelo de calibração linear;
Distribuição simetrica;
Outliers
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APA ·
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Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
William Pereira Marciano, F. (2012). Modelo de calibração com erros simétricos
. (Thesis). Universidade Federal de Pernambuco. Retrieved from http://repositorio.ufpe.br/handle/123456789/6639
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):
William Pereira Marciano, Francisco. “Modelo de calibração com erros simétricos
.” 2012. Thesis, Universidade Federal de Pernambuco. Accessed March 05, 2021.
http://repositorio.ufpe.br/handle/123456789/6639.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
William Pereira Marciano, Francisco. “Modelo de calibração com erros simétricos
.” 2012. Web. 05 Mar 2021.
Vancouver:
William Pereira Marciano F. Modelo de calibração com erros simétricos
. [Internet] [Thesis]. Universidade Federal de Pernambuco; 2012. [cited 2021 Mar 05].
Available from: http://repositorio.ufpe.br/handle/123456789/6639.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
William Pereira Marciano F. Modelo de calibração com erros simétricos
. [Thesis]. Universidade Federal de Pernambuco; 2012. Available from: http://repositorio.ufpe.br/handle/123456789/6639
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Rochester
13.
Evans, Katie N.; Love, Tanzy.
Extensions to model-based clustering for mixed-type data
: a new model framework, variable selection, and outlier
detection.
Degree: PhD, 2014, University of Rochester
URL: http://hdl.handle.net/1802/28443
► In many disciplines, such as marketing, biology, and bioinformatics, there is an increasing desire to identify distinct subgroups of observations within an observed data set;…
(more)
▼ In many disciplines, such as marketing, biology,
and bioinformatics, there is an
increasing desire to identify
distinct subgroups of observations within an observed
data set;
model-based cluster analysis provides a statistical framework to
identify
and evaluate the appropriateness of these groups. Within
cluster analysis,
the primary objective is to determine the
classification of the observations into
distinct groups, but
parameter estimation, used to describe these groups, is also
important. A complete analysis should consider the proper
distributional form
for all variables, identify important
variables for distinguishing clusters, evaluate
model fit, and
identify (and appropriately handle) any atypical observations.
Our
new framework for model-based clustering on data with continuous
and
discrete variables extends the cluster variance structure
framework set forth by
Fraley and Raftery (1999). In modeling how
each variable contributes to cluster
determination, we allow for
dependencies within and between continuous and
discrete
variables.
We also modify and extend existing likelihood-based
variable selection procedures
to accommodate data with variables
of mixed-distributional forms and
only require at least one
continuous variable. Simulation study results showed
desirable
properties of our method when applied to data with variables of
mixed-distributional
forms; our method also outperforms existing
methods when applied
to normally distributed data.
In model-based
clustering based on normal-mixture models, a few outlying
observations
can influence the number of clusters and their
structure. We developed
a method to identify these few points (as
opposed to identifying clusters amidst a field of noise.) We
identify outliers as those observations in a cluster with very few
members, or for which the cluster-specific variance with and
without the observation
is very different. Results from a
simulation study demonstrated the ability of
our method to detect
true outliers without falsely identifying many non-outliers
and
improved performance over other approaches, under most scenarios.
These methods are applied to data from the Seychelles Child
Development
Nutrition Study to identify distinct diet subgroups of
pregnant mothers, the variables
important in defining these
clusters, and whether any mothers exhibit atypical
eating
patterns. We identified five variables important in defining six
unique
diet groups and nine mothers with unusual eating
patterns.
Subjects/Keywords: Mixed-type data; Feature selection; Outliers; Clustering
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APA ·
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MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Evans, Katie N.; Love, T. (2014). Extensions to model-based clustering for mixed-type data
: a new model framework, variable selection, and outlier
detection. (Doctoral Dissertation). University of Rochester. Retrieved from http://hdl.handle.net/1802/28443
Chicago Manual of Style (16th Edition):
Evans, Katie N.; Love, Tanzy. “Extensions to model-based clustering for mixed-type data
: a new model framework, variable selection, and outlier
detection.” 2014. Doctoral Dissertation, University of Rochester. Accessed March 05, 2021.
http://hdl.handle.net/1802/28443.
MLA Handbook (7th Edition):
Evans, Katie N.; Love, Tanzy. “Extensions to model-based clustering for mixed-type data
: a new model framework, variable selection, and outlier
detection.” 2014. Web. 05 Mar 2021.
Vancouver:
Evans, Katie N.; Love T. Extensions to model-based clustering for mixed-type data
: a new model framework, variable selection, and outlier
detection. [Internet] [Doctoral dissertation]. University of Rochester; 2014. [cited 2021 Mar 05].
Available from: http://hdl.handle.net/1802/28443.
Council of Science Editors:
Evans, Katie N.; Love T. Extensions to model-based clustering for mixed-type data
: a new model framework, variable selection, and outlier
detection. [Doctoral Dissertation]. University of Rochester; 2014. Available from: http://hdl.handle.net/1802/28443
Universidade do Rio Grande do Sul
14.
Bisognin, Cleber.
Estimação e previsão em processos sarfima(p, d, q) x (P, D, Q)ѕ[subscrito] na presença de outliers.
Degree: 2007, Universidade do Rio Grande do Sul
URL: http://hdl.handle.net/10183/137796
► Neste trabalho analisamos alguns processos com a propriedade de longa dependência e sazonalidade. Nosso estudo tem por objetivo principal estudar os processos k Factor GARMA…
(more)
▼ Neste trabalho analisamos alguns processos com a propriedade de longa dependência e sazonalidade. Nosso estudo tem por objetivo principal estudar os processos k Factor GARMA p, λ, u, q e SARFIMA p, d, q P, D, Q s, onde s é a sazonalidade. Para os processos k Factor GARMA p, λ, u, q , baseados no conheci- mento das freqüências de Gegenbauer, propomos estimadores da classe semi- paramétrica para o correspondente parâmetro λ. Apresentamos importantes resultados envolvendo a função densidade espectral e os coeficientes das representações auto-regressiva e média móvel destes processos. No estudo dos processos SARFIMA p, d, q P, D, Q s, demonstramos algumas propriedades destes processos, tais como a expressão da função densidade espectral, o seu comportamento próximo às freqüências sazonais, a estacionariedade, as dependências intermediária e longa, a função de autocovariância e a sua expressão assintótica. Investigamos também as condições necessárias e suficientes para a causalidade e a inversibilidade destes processos SARFIMA. Analisamos a ergodicidade e apresentamos a previsão de erro quadrático médio mínimo para estes processos. Apresentamos diversos estimadores na classe dos métodos semiparamétricos para estimar, tanto o parâmetro de diferenciação d, bem como o de diferenciação sazonal D. Na classe paramétrica, apresentamos um método que estima todos os parâmetros do processo. Propomos nova metodologia de estimação para os parâmetros d e D, os chamados estimadores robustos. Introduzimos dois métodos de contaminação por outliers, o modelo multiparamétrico e a contaminação por mistura. Através de simulações de Monte Carlo, analisamos o comportamento dos estimadores das classes semiparamétrica e paramétrica para os parâmetros do processo SARFIMA. Nestas simulações, os processos são considerados com e sem contaminação por outliers do tipo aditivo e de inovação. Apresentamos o teste de verossimilhança para detectar e identificar outliers em processos SARFIMA. Desenvolvemos um estimador para a magnitude de outliers dos tipos aditivo e de inovação. Demonstramos que este estimadoré não viciado e normalmente distribuído. Realizamos a análise da série temporal dos níveis mensais do rio Nilo, em Aswan, com e sem contaminação por outliers do tipo aditivo.
In this work we analyze some processes with long memory and seasonality properties. The main goal is to study the k Factor GARMA p, λ, u, q and SARFIMA p, d, q P, D, Q s processes, where s is the seasonality. For the k Factor GARMA p, λ, u, q process, based on the knowledge of the Gegenbauer frequencies, we propose some estimators in the semiparame- tric class for the corresponding parameter λ. We present important results related to the spectral density function and to the coefficients of the autore- gressive and moving average infinite representations for these processes. In the study of the SARFIMA p, d, q P, D, Q s processes, we prove several properties, such as its spectral density function expression and its behavior near the seasonal frequencies, the stationarity, the…
Advisors/Committee Members: Lopes, Silvia Regina Costa.
Subjects/Keywords: Matematica : Processos estocasticos; Outliers; Processos sarfima
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APA ·
Chicago ·
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Export
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Manager
APA (6th Edition):
Bisognin, C. (2007). Estimação e previsão em processos sarfima(p, d, q) x (P, D, Q)ѕ[subscrito] na presença de outliers. (Thesis). Universidade do Rio Grande do Sul. Retrieved from http://hdl.handle.net/10183/137796
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):
Bisognin, Cleber. “Estimação e previsão em processos sarfima(p, d, q) x (P, D, Q)ѕ[subscrito] na presença de outliers.” 2007. Thesis, Universidade do Rio Grande do Sul. Accessed March 05, 2021.
http://hdl.handle.net/10183/137796.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Bisognin, Cleber. “Estimação e previsão em processos sarfima(p, d, q) x (P, D, Q)ѕ[subscrito] na presença de outliers.” 2007. Web. 05 Mar 2021.
Vancouver:
Bisognin C. Estimação e previsão em processos sarfima(p, d, q) x (P, D, Q)ѕ[subscrito] na presença de outliers. [Internet] [Thesis]. Universidade do Rio Grande do Sul; 2007. [cited 2021 Mar 05].
Available from: http://hdl.handle.net/10183/137796.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Bisognin C. Estimação e previsão em processos sarfima(p, d, q) x (P, D, Q)ѕ[subscrito] na presença de outliers. [Thesis]. Universidade do Rio Grande do Sul; 2007. Available from: http://hdl.handle.net/10183/137796
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
15.
Braumann, Maria Manuela São Pedro Abreu.
Sobre testes de detecção de "outliers" em populações exponenciais.
Degree: 1994, Universidade de Évora
URL: http://www.rcaap.pt/detail.jsp?id=oai:dspace.uevora.pt:10174/11835
► É óbvio o interesse da detecção de "outliers" em amostras, uma vez que estas podem ser contaminadas por essa observações "surpreendentes", isto é, a informação…
(more)
▼ É óbvio o interesse da detecção de "outliers" em amostras, uma vez que estas podem ser contaminadas por essa observações "surpreendentes", isto é, a informação dada pelas amostras poderá ser distorcida.
Torna-se portanto fundamental procurar meios de interpretar ou reconhecer "outliers". No entanto, até agora, a detecção de "outliers" não tem sido feita por métodos rigorosos e objectivos, uma vez que na selecção das observações a testar se têm utilizado apenas processos intuitivos ( os candidatos a "outliers" são escolhidos empiricamente, a priori ).
Com o método GAN (generativo de alternativa natural), Rosado, na sua tese de doutoramento (1984), trata o problema de uma forma objectiva, sendo a observação rejeitada como "outlier" escolhida a posteriori, uma vez rejeitada a homogeneidade nas observações.
A detecção e tratamento de "outliers" têm importância em todas as áreas científicas e aplicações que recorrem a estudos estatísticos. As técnicas de detecção e identificação de "outliers" são também importantes para a eliminação de elementos estranhos em amostras de populações e para o ajustamento de modelos regressionais ou outros (através do estudo de existência de "outliers" nos resíduos).
A distribuição exponencial tem um papel relevante em muitas aplicações, principalmente quando se pretende estudar tempos de vida de sistemas (mecânicos, electrónicos, biológicos ou outros) ou suas componentes.
A "performance" dos testes desenvolvidos para detecção e identificação de "outliers" em populações exponenciais, quer os clássicos quer os novos testes obtidos por Rosado, não era conhecida, não obstante a existência de critérios de medição de "performance" para testes desta natureza propostos na literatura e aceites como relevantes.
Um dos objectivos deste trabalho é a obtenção de novas estatísticas de teste obtidas pelo método GAN, de forma a cobrir todas as hipóteses possíveis (para um "outlier") no que respeita à distribuição exponencial. Um outro objectivo é a elaboração de tabelas de valores críticos e, por fim, a determinação das medidas de "performance" dos testes já existentes e dos novos obtidos neste trabalho. Será feito um estudo comparativo da "performance" dos vários testes, estudo esse que trará consequências sobre a sua aplicação prática.
Posto isto, vejamos sucintamente no que consta o trabalho.
No capítulo I começaremos por ver o que é um "outlier", como aparece, como o detectar
e por fim como o tratar (o que fazer com ele). Nesta parte do trabalho seguiremos de perto Braumann (1989). A seguir vamos ver o que são testes de discordância para "outliers"; serão apresentados os testes tradicionais e abordado um novo teste de Rosado (1984). No ponto 1.5 abordaremos as medidas de "performance" dos testes.
Já no capítulo II será desenvolvido o novo método de Rosado (1984), o método generativo de alternativa natural (método GAN) e com base nele obteremos novas estatísticas de teste para o caso da distribuição exponencial. Para além da obtenção destas novas estatísticas serão também apresentadas as estatísticas já…
Subjects/Keywords: Probabilidades; Estatística; Outliers
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APA (6th Edition):
Braumann, M. M. S. P. A. (1994). Sobre testes de detecção de "outliers" em populações exponenciais. (Thesis). Universidade de Évora. Retrieved from http://www.rcaap.pt/detail.jsp?id=oai:dspace.uevora.pt:10174/11835
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):
Braumann, Maria Manuela São Pedro Abreu. “Sobre testes de detecção de "outliers" em populações exponenciais.” 1994. Thesis, Universidade de Évora. Accessed March 05, 2021.
http://www.rcaap.pt/detail.jsp?id=oai:dspace.uevora.pt:10174/11835.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Braumann, Maria Manuela São Pedro Abreu. “Sobre testes de detecção de "outliers" em populações exponenciais.” 1994. Web. 05 Mar 2021.
Vancouver:
Braumann MMSPA. Sobre testes de detecção de "outliers" em populações exponenciais. [Internet] [Thesis]. Universidade de Évora; 1994. [cited 2021 Mar 05].
Available from: http://www.rcaap.pt/detail.jsp?id=oai:dspace.uevora.pt:10174/11835.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Braumann MMSPA. Sobre testes de detecção de "outliers" em populações exponenciais. [Thesis]. Universidade de Évora; 1994. Available from: http://www.rcaap.pt/detail.jsp?id=oai:dspace.uevora.pt:10174/11835
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
George Mason University
16.
Rogers, James P.
Detection of Outliers in Spatial-temporal Data A
.
Degree: 2011, George Mason University
URL: http://hdl.handle.net/1920/6320
► Outlier detection is an important data mining task that is focused on the discovery of objects that deviate significantly when compared with a set of…
(more)
▼ Outlier detection is an important data mining task that is focused on the discovery
of objects that deviate significantly when compared with a set of observations that are
considered typical. Outlier detection can reveal objects that behave anomalously with
respect to other observations, and these objects may highlight current or future problems.
Previous outlier detection methods have focused primarily on only one non-spatial numerical
attribute and have not successfully dealt with multiple dimensions. Many previous
methods assume a Gaussian distribution of the data which is probably a major fallacy
in determining
outliers for spatial-temporal data. Most previous efforts did not provide
a statistical confidence measure, but including a confidence measure should improve the
detection of
outliers. Outlier detection is often complicated by noise in the data, so a good
outlier detection methodology should be successful in identifying
outliers in noisy data.
Global outlier methods calculate a single outlier statistic that summarizes the
outliers for
the entire geographic area and temporal duration, while local outlier methods calculate a
outlier statistic for each feature based on its similarity to its neighbors. Previous methods
have not been able to determine
outliers as the vector of attributes, location, and time
change. The objective of my research is to devise a methodology to address these problems
and challenges.
The objective of my research is to develop a robust method of diagnosing
outliers and
to extend it to detecting
outliers in spatial-temporal data. A spatial-temporal outlier is
an observation whose values are significantly different from those of other spatially and
temporally referenced objects in its spatial-temporal neighborhood.
Geographic phenomena are difficult to analyze using traditional data mining methods.
Determining relationships among phenomena as they move and change over time is not
possible by means of human analysis of spatial-temporal data streams. Also, the volume
of spatial-temporal data being collected is increasing steadily due to the usage of cameras,
sensors, and mobile devices (e.g., cell phones) and is too much data for the human to
analyze.
My method, unlike many detection methods found in the literature, does not require
the user to enter the number of
outliers to be found or the percentage of
outliers to be
found and does not assume any distribution of the data (e.g., Gaussian). My method only
requires the input of two parameters: the statistical confidence level and the number of
nearest neighbors, and only the statistical confidence level is significant. My method allows
for different ways to measure the degree of non-conformity and works for high-dimensional
data, noisy data, and data with or without clustering information.
The basic outlier detection method was extended to spatial-temporal data by using
kernels for the vector of attributes, spatial, and time that provides a capability to focus
outlier detection on local neighborhoods,…
Advisors/Committee Members: Barbara, Daniel (advisor).
Subjects/Keywords: outliers;
transduction;
spatial;
probability;
temporal;
confidence
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APA (6th Edition):
Rogers, J. P. (2011). Detection of Outliers in Spatial-temporal Data A
. (Thesis). George Mason University. Retrieved from http://hdl.handle.net/1920/6320
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):
Rogers, James P. “Detection of Outliers in Spatial-temporal Data A
.” 2011. Thesis, George Mason University. Accessed March 05, 2021.
http://hdl.handle.net/1920/6320.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Rogers, James P. “Detection of Outliers in Spatial-temporal Data A
.” 2011. Web. 05 Mar 2021.
Vancouver:
Rogers JP. Detection of Outliers in Spatial-temporal Data A
. [Internet] [Thesis]. George Mason University; 2011. [cited 2021 Mar 05].
Available from: http://hdl.handle.net/1920/6320.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Rogers JP. Detection of Outliers in Spatial-temporal Data A
. [Thesis]. George Mason University; 2011. Available from: http://hdl.handle.net/1920/6320
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
McMaster University
17.
Clark, Katharine.
Outlier Detection in Gaussian Mixture Models.
Degree: MSc, 2020, McMaster University
URL: http://hdl.handle.net/11375/25930
► Unsupervised classification is a problem often plagued by outliers, yet there is a paucity of work on handling outliers in unsupervised classification. Mixtures of Gaussian…
(more)
▼ Unsupervised classification is a problem often plagued by outliers, yet there is a paucity of work on handling outliers in unsupervised classification. Mixtures of Gaussian distributions are a popular choice in model-based clustering. A single outlier can affect parameters estimation and, as such, must be accounted for. This issue is further complicated by the presence of multiple outliers. Predicting the proportion of outliers correctly is paramount as it minimizes misclassification error. It is proved that, for a finite Gaussian mixture model, the log-likelihoods of the subset models are distributed according to a mixture of beta-type distributions. This relationship is leveraged in two ways. First, an algorithm is proposed that predicts the proportion of outliers by measuring the adherence of a set of subset log-likelihoods to a beta-type mixture reference distribution. This algorithm removes the least likely points, which are deemed outliers, until model assumptions are met. Second, a hypothesis test is developed, which, at a chosen significance level, can test whether a dataset contains a single outlier.
Thesis
Master of Science (MSc)
Advisors/Committee Members: McNicholas, Paul, Statistics.
Subjects/Keywords: clustering; outliers; model selection; mixture models
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APA (6th Edition):
Clark, K. (2020). Outlier Detection in Gaussian Mixture Models. (Masters Thesis). McMaster University. Retrieved from http://hdl.handle.net/11375/25930
Chicago Manual of Style (16th Edition):
Clark, Katharine. “Outlier Detection in Gaussian Mixture Models.” 2020. Masters Thesis, McMaster University. Accessed March 05, 2021.
http://hdl.handle.net/11375/25930.
MLA Handbook (7th Edition):
Clark, Katharine. “Outlier Detection in Gaussian Mixture Models.” 2020. Web. 05 Mar 2021.
Vancouver:
Clark K. Outlier Detection in Gaussian Mixture Models. [Internet] [Masters thesis]. McMaster University; 2020. [cited 2021 Mar 05].
Available from: http://hdl.handle.net/11375/25930.
Council of Science Editors:
Clark K. Outlier Detection in Gaussian Mixture Models. [Masters Thesis]. McMaster University; 2020. Available from: http://hdl.handle.net/11375/25930
University of Minnesota
18.
Gohar, Usman.
Scalable Techniques for Trajectory Outlier Detection.
Degree: MS, Computer Science, 2019, University of Minnesota
URL: http://hdl.handle.net/11299/206183
► The recent improvements in tracking devices and positioning satellites have led to an increased availability of spatial data describing the movement of objects such as…
(more)
▼ The recent improvements in tracking devices and positioning satellites have led to an increased availability of spatial data describing the movement of objects such as vehicles, animals, etc. Such data is obtained by recording the positions of the objects at regular intervals and then arranging the collected positions of each object into a time-ordered sequence called trajectory. The high availability of trajectory data has permitted the execution of data analysis operations such as trajectory outlier detection, which consists in the identification of those trajectories that behave much differently from the rest of the trajectories in a database. There are several time-critical applications such as traffic management systems, security surveillance systems and real-time stock monitoring, etc. which can be solved through trajectory outlier detection. However, the time-critical nature of such applications imposes tight constraints on the execution time of trajectory outlier detection algorithms. To deal with these constraints, we propose three strategies to accelerate the performance of the existing trajectory outlier detection algorithm ODMTS. First, we consider using spatial data structures such as k-d trees and R-trees to improve the running time performance of the ODMTS algorithm for trajectory outlier detection. Our results showed that by using R-trees we can improve the execution time of ODMTS by a factor of 10X. Our second strategy consists in harnessing the power of multiple CPUs to parallelize the ODMTS algorithm. This strategy yielded an execution time improvement that scales linearly with the number of cores, which in our case achieved 32X. The third strategy consists in a new partitioning-based streaming algorithm, called PDMTS, for trajectory outlier detection that leverages data streams in order to find trajectory outliers. Our experiments on real-life datasets showed that our proposed algorithm detected almost 45% outliers more than ODMTS, but is almost 18% slower than compared to ODMTS due to the partitioning step.
Subjects/Keywords: Outlier Detection; Outliers; Time-Series; Trajectories
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APA ·
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APA (6th Edition):
Gohar, U. (2019). Scalable Techniques for Trajectory Outlier Detection. (Masters Thesis). University of Minnesota. Retrieved from http://hdl.handle.net/11299/206183
Chicago Manual of Style (16th Edition):
Gohar, Usman. “Scalable Techniques for Trajectory Outlier Detection.” 2019. Masters Thesis, University of Minnesota. Accessed March 05, 2021.
http://hdl.handle.net/11299/206183.
MLA Handbook (7th Edition):
Gohar, Usman. “Scalable Techniques for Trajectory Outlier Detection.” 2019. Web. 05 Mar 2021.
Vancouver:
Gohar U. Scalable Techniques for Trajectory Outlier Detection. [Internet] [Masters thesis]. University of Minnesota; 2019. [cited 2021 Mar 05].
Available from: http://hdl.handle.net/11299/206183.
Council of Science Editors:
Gohar U. Scalable Techniques for Trajectory Outlier Detection. [Masters Thesis]. University of Minnesota; 2019. Available from: http://hdl.handle.net/11299/206183
19.
Adnan, Mian Arif Shams.
A least deviation approach for credibility estimation : an alternative approach to Buhlmann's credibility.
Degree: MA, 2016, Ball State University
URL: http://cardinalscholar.bsu.edu/handle/123456789/200302
► All previously derived univariate measures of credibility are much affected by outlier(s) and their multivariate or hierarchical or regression counterparts on the other hand, fail…
(more)
▼ All previously derived univariate measures of credibility are much affected by
outlier(s) and their multivariate or hierarchical or regression counterparts on the other hand, fail to
cope with the observations of non-normal populations. All of them considered traditional measure
of risk (that uses the squared error loss function) and variance (or, standard deviation) that fail to
capture fully the “true dispersion” of the data for estimating credibility. Moreover, maximum of
the credibility estimators are based on normality approximations of the parent population of the
data.
Attempts have been made here to find new robust measures of credibility which are based on all
observations and one dimensional dispersion measures. These measures are useable to any loss
distribution irrespective of shape of that distribution (symmetric and/or asymmetric loss
distribution) and are less affected by outlier(s) and/or extreme observation(s).
Advisors/Committee Members: Dean, Curtis G. (advisor).
Subjects/Keywords: Outliers (Statistics); Nonparametric statistics.; Credibility theory (Insurance)
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APA (6th Edition):
Adnan, M. A. S. (2016). A least deviation approach for credibility estimation : an alternative approach to Buhlmann's credibility. (Masters Thesis). Ball State University. Retrieved from http://cardinalscholar.bsu.edu/handle/123456789/200302
Chicago Manual of Style (16th Edition):
Adnan, Mian Arif Shams. “A least deviation approach for credibility estimation : an alternative approach to Buhlmann's credibility.” 2016. Masters Thesis, Ball State University. Accessed March 05, 2021.
http://cardinalscholar.bsu.edu/handle/123456789/200302.
MLA Handbook (7th Edition):
Adnan, Mian Arif Shams. “A least deviation approach for credibility estimation : an alternative approach to Buhlmann's credibility.” 2016. Web. 05 Mar 2021.
Vancouver:
Adnan MAS. A least deviation approach for credibility estimation : an alternative approach to Buhlmann's credibility. [Internet] [Masters thesis]. Ball State University; 2016. [cited 2021 Mar 05].
Available from: http://cardinalscholar.bsu.edu/handle/123456789/200302.
Council of Science Editors:
Adnan MAS. A least deviation approach for credibility estimation : an alternative approach to Buhlmann's credibility. [Masters Thesis]. Ball State University; 2016. Available from: http://cardinalscholar.bsu.edu/handle/123456789/200302
20.
Giroldo, Fabíola Rocha de Santana.
Alguns métodos robustos para detectar outliers multivariados.
Degree: Mestrado, Estatística, 2008, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/45/45133/tde-20102009-211316/
;
► Observações ou outliers estão quase sempre presentes em qualquer conjunto de dados, seja ele grande ou pequeno. Isso pode ocorrer por erro no armazenamento dos…
(more)
▼ Observações ou outliers estão quase sempre presentes em qualquer conjunto de dados, seja ele grande ou pequeno. Isso pode ocorrer por erro no armazenamento dos dados ou por existirem realmente alguns pontos diferentes dos demais. A presença desses pontos pode causar distorções nos resultados de modelos e estimativas. Por isso, a sua detecção é muito importante e deve ser feita antes do início de uma análise mais profunda dos dados. Após esse diagnóstico, pode-se tomar uma decisão a respeito dos pontos atípicos. Uma possibilidade é corrigi-los caso tenha ocorrido erro na transcrição dos dados. Caso sejam pontos válidos, eles devem ser tratados de forma diferente dos demais, seja com uma ponderação, seja com uma análise especial. Nos casos univariado e bivariado, o outlier pode ser detectado analisando-se o gráfico de dispersão que mostra o comportamento de cada observação do conjunto de dados de interesse. Se houver pontos distantes da massa de dados, eles devem ser considerados atípicos. No caso multivariado, a detecção por meio de gráficos torna-se um pouco mais complexa porque a análise deveria ser feita observando-se duas variáveis por vez, o que tornaria o processo longo e pouco confiável, pois um ponto pode ser atípico com relação a algumas variáveis e não ser com relação a outras, o que faria com que o resultado ficasse mascarado. Neste trabalho, alguns métodos robustos para detecção de outliers em dados multivariados são apresentados. A aplicação de cada um dos métodos é feita para um exemplo. Além disso, os métodos são comparados de acordo com o resultado que cada um apresentar para o exemplo em questão e via simulação.
Unusual observations or outliers are frequent in any data set, if it is large or not. Outliers may occur by typing mistake or by the existence of observations that are really different from the others. The presence of this observations may distort the results of models and estimates. Therefore, their detection is very important and it is recommended to be performed before any detailed analysis, when a decision can be taken about these atypical observations. A possibility is to correct these observations if the problem occurred with the construction of the data set. If the observations are correct, different strategies can be adopted, with some weights or with special analysis. In univariate and bivariate data sets, outliers can be detected analyzing the scatter plot. Observations distant from the cloud formed by the data set are considered unusual. In multivariate data sets, the detection of outliers using graphics is more difficult because we have to analyse a couple of variables each time, which results is a long and less reliable process because we can find an observation that is unusual for one variable and not unusual for the others, masking the results. In this work, some robust methods for detection of multivariate outliers are presented. The application of each one is done for an example. Moreover, the methods are compared by the results of each one in the example and by simulation.
Advisors/Committee Members: Barroso, Lucia Pereira.
Subjects/Keywords: dados multivariados; métodos robustos; multivariate data; multivariate outliers; outliers multivariados; robust methods
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APA ·
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MLA ·
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to Zotero / EndNote / Reference
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APA (6th Edition):
Giroldo, F. R. d. S. (2008). Alguns métodos robustos para detectar outliers multivariados. (Masters Thesis). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/45/45133/tde-20102009-211316/ ;
Chicago Manual of Style (16th Edition):
Giroldo, Fabíola Rocha de Santana. “Alguns métodos robustos para detectar outliers multivariados.” 2008. Masters Thesis, University of São Paulo. Accessed March 05, 2021.
http://www.teses.usp.br/teses/disponiveis/45/45133/tde-20102009-211316/ ;.
MLA Handbook (7th Edition):
Giroldo, Fabíola Rocha de Santana. “Alguns métodos robustos para detectar outliers multivariados.” 2008. Web. 05 Mar 2021.
Vancouver:
Giroldo FRdS. Alguns métodos robustos para detectar outliers multivariados. [Internet] [Masters thesis]. University of São Paulo; 2008. [cited 2021 Mar 05].
Available from: http://www.teses.usp.br/teses/disponiveis/45/45133/tde-20102009-211316/ ;.
Council of Science Editors:
Giroldo FRdS. Alguns métodos robustos para detectar outliers multivariados. [Masters Thesis]. University of São Paulo; 2008. Available from: http://www.teses.usp.br/teses/disponiveis/45/45133/tde-20102009-211316/ ;
UNIVERSIDADE FEDERAL DE OURO PRETO
21.
Fabricio Geraldo Valadares.
DETECÃÃO DE OUTLIERS MULTIVARIADOS EM REDES DE SENSORES.
Degree: 2012, UNIVERSIDADE FEDERAL DE OURO PRETO
URL: http://www.tede.ufop.br/tde_busca/arquivo.php?codArquivo=925
► Esse trabalho apresenta uma anÃlise, via detecÃÃo de outliers, sobre os dados multivariados proveniente de uma rede de sensores. Inicialmente, caracterizamos o problema de detecÃÃo…
(more)
▼ Esse trabalho apresenta uma anÃlise, via detecÃÃo de outliers, sobre os dados multivariados proveniente de uma rede de sensores. Inicialmente, caracterizamos o problema de detecÃÃo de outliers nestas redes. Em seguida, realizamos, via simulaÃÃo, uma comparaÃÃo entre trÃs mÃtodos gerais para a identificaÃÃo dos outliers, Minimum Volume Ellipsoid (MVE), Minimum Covariance Determinant (MCD) e Max-Eigen Difference (MED), considerando cenÃrios especÃficos de uma rede de sensores. Os dados utilizados na simulaÃÃo foram gerados a partir de uma base de dados reais proveniente da mediÃÃo de poluentes no ar. Essa geraÃÃo nos permitiu representar o cenÃrio de uma rede de sensores. O fenÃmeno avaliado segue um comportamento Normal, e utilizamos outras duas distribuiÃÃes, Skew-Normal e T-Student, para representar a imprecisÃo inerente do processo de sensoriamento, que nem sempre consegue representar satisfatoriamente o ambiente monitorado. Adicionalmente, representamos a presenÃa de ruÃdos nos dados (outliers pontuais), inseridos com base em uma distribuiÃÃo de Bernoulli. Essa distribuiÃÃo foi utilizada para selecionar quais amostras seriam substituÃdas por ruÃdos. A avaliaÃÃo da representatividade dos dados apÃs a remoÃÃo dos outliers à realizada por intermÃdio de um ferramental estatÃstico formado pelos seguintes testes, valor absoluto do erro relativo, ANOVA, medidas de tendÃncia central e a contagem de outliers. Todas as simulaÃÃes foram realizadas no software estatÃstico R. Os resultados das avaliaÃÃes demonstraram que os erros encontrados podem ser tolerados por grande parte das aplicaÃÃes em redes de sensores, quando aplicados os mÃtodos MVE e MCD. O mÃtodo MED nÃo conseguiu identificar todos os outliers, logo, sua aplicaÃÃo nÃo traz benefÃcios Ãs aplicaÃÃes consideradas.
This work presents an analysis based on outliers detection on multivariate dataset of sensor networks. Initially, we characterize the outliers detection problem in these networks. Then, three general methods for outliers detection methods Minimum Volume Ellipsoid (MVE), Minimum Covariance Determinant (MCD) and Max-Eigen Difference (MED) were used and evalueted. The dataset used in the simulation was generated from an air pollutants dataset. This generation allowed the use of this dataset in sensor networks scenarios. The phenomenon has characterized by a Normal distribution. To represent the sensor perception fails, two different distributions was used, the Skew-Normal and T-Student. In addition, the sensor noise was inserted by using a Bernoulli process. The data representativeness, after the outlier removal, was performed by statistical tools: the absolute relative error, ANOVA, measures of central tendency and the number of outliers. The simulations were performed by software R. The results showed that the MVE and MCD can be used satisfatory in general sensor networks applications. The MED does not remove all outliers, so, its usage is not recommended in these applications.
Advisors/Committee Members: Ricardo Augusto Rabelo Oliveira, Ãlvaro Rodrigues Pereira Junior, Andrà Luiz Lins de Aquino, Corina da Costa Freitas.
Subjects/Keywords: outliers; outliers; multivariate data; CIENCIA DA COMPUTACAO; Redes de sensores; dados multivariados; Sensor networks
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APA (6th Edition):
Valadares, F. G. (2012). DETECÃÃO DE OUTLIERS MULTIVARIADOS EM REDES DE SENSORES. (Thesis). UNIVERSIDADE FEDERAL DE OURO PRETO. Retrieved from http://www.tede.ufop.br/tde_busca/arquivo.php?codArquivo=925
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):
Valadares, Fabricio Geraldo. “DETECÃÃO DE OUTLIERS MULTIVARIADOS EM REDES DE SENSORES.” 2012. Thesis, UNIVERSIDADE FEDERAL DE OURO PRETO. Accessed March 05, 2021.
http://www.tede.ufop.br/tde_busca/arquivo.php?codArquivo=925.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Valadares, Fabricio Geraldo. “DETECÃÃO DE OUTLIERS MULTIVARIADOS EM REDES DE SENSORES.” 2012. Web. 05 Mar 2021.
Vancouver:
Valadares FG. DETECÃÃO DE OUTLIERS MULTIVARIADOS EM REDES DE SENSORES. [Internet] [Thesis]. UNIVERSIDADE FEDERAL DE OURO PRETO; 2012. [cited 2021 Mar 05].
Available from: http://www.tede.ufop.br/tde_busca/arquivo.php?codArquivo=925.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Valadares FG. DETECÃÃO DE OUTLIERS MULTIVARIADOS EM REDES DE SENSORES. [Thesis]. UNIVERSIDADE FEDERAL DE OURO PRETO; 2012. Available from: http://www.tede.ufop.br/tde_busca/arquivo.php?codArquivo=925
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Universidade Federal de Santa Maria
22.
Gustavo Griebeler.
CONTROLE DE QUALIDADE DE ANÁLISES DE SOLOS DA REDE ROLAS-RS/SC E PROCEDIMENTOS ESTATÍSTICOS ALTERNATIVOS.
Degree: 2012, Universidade Federal de Santa Maria
URL: http://coralx.ufsm.br/tede/tde_busca/arquivo.php?codArquivo=4151
► Os resultados de análises químicas de amostras de solo devem apresentar exatidão satisfatória para que não sejam induzidos erros de recomendação da adubação e calagem.…
(more)
▼ Os resultados de análises químicas de amostras de solo devem apresentar exatidão satisfatória para que não sejam induzidos erros de recomendação da adubação e calagem. O controle de qualidade dos laboratórios da rede ROLAS-RS/SC avalia a exatidão média anual dos resultados, sendo a mesma estabelecida em função do afastamento em desvios padrão de um resultado em relação à mediana das análise de cada uma das amostras de solo realizadas ao longo do ano. Nesse sistema, é necessário que os dados apresentem distribuição normal para que a mediana seja assumida como estimativa do valor central das amostras de solos, associada à ausência de
outliers, pois estes alteram a magnitude do desvio padrão e, consequentemente, a exatidão. O procedimento matemático de cálculo da exatidão média também pode permitir que os asteriscos recebidos em atributos de análise inexatos sejam contrabalanceados pelos atributos exatos. Além disso, os critérios de cancelamento de asteriscos podem estar em desacordo com a incerteza analítica associada aos métodos. Portanto, o objetivo do trabalho foi testar a distribuição normal dos resultados do controle de qualidade da rede ROLAS-RS/SC, identificar a presença de
outliers, avaliar o procedimento de cálculo da exatidão e quantificar analiticamente a incerteza associada aos métodos de extração e determinação de P e K para verificar como estes fatores podem afetar a exatidão dos laboratórios. O teste de Lilliefors foi aplicado para avaliar a normalidade e os
outliers foram identificados pelo método dos quartis. Procedimentos para avaliar a exatidão pelo ajuste à distribuição normal através da eliminação dos
outliers foram testados, além da substituição da mediana pela média e avaliação do procedimento de cálculo da exatidão por atributo de análise das amostras de solo ao invés da exatidão média de todos os atributos. Repetições das análises de P e K foram realizadas para verificar a variabilidade intrínseca dos métodos. Somente 59% dos dados apresentaram distribuição normal, indicando que 41% das análises foram avaliadas em desacordo com os pressupostos estatísticos. A exclusão dos
outliers elevou de 59 para 75% o número de análises com distribuição normal, que tornou o método de avaliação mais rígido, uma vez que diminuiu o número de laboratórios com a exatidão mínima exigida de 85%. Em dados com distribuição normal, a média parece melhor estimar o valor verdadeiro que a mediana. Dados sem distribuição normal por ultrapassarem as faixas de trabalho devem ser eliminados, enquanto aqueles enquadrados dentro das faixas de trabalho e que apresentam amplitude inferior a 1,5 vezes a distância interquartílica não devem ser excluídos para o cálculo da exatidão. O procedimento que calcula a exatidão média anual oculta atributos com exatidão inferior ao mínimo preconizado pelo sistema. A variabilidade intrínseca associada aos métodos de análise indica que os critérios de cancelamento de asteriscos do P devem ser reavaliados enquanto os critérios referentes ao K parecem estar adequados, contudo, deve-se aprofundar…
Advisors/Committee Members: Sirio Wietholter, Leandro Souza da Silva, Alberto Cargnelutti Filho.
Subjects/Keywords: Outliers; Normalidade; Exatidão; Variabilidade; Incerteza; CIENCIA DO SOLO; Normality; Outliers; Accuracy; Variability; Uncertainity
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APA (6th Edition):
Griebeler, G. (2012). CONTROLE DE QUALIDADE DE ANÁLISES DE SOLOS DA REDE ROLAS-RS/SC E PROCEDIMENTOS ESTATÍSTICOS ALTERNATIVOS. (Thesis). Universidade Federal de Santa Maria. Retrieved from http://coralx.ufsm.br/tede/tde_busca/arquivo.php?codArquivo=4151
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):
Griebeler, Gustavo. “CONTROLE DE QUALIDADE DE ANÁLISES DE SOLOS DA REDE ROLAS-RS/SC E PROCEDIMENTOS ESTATÍSTICOS ALTERNATIVOS.” 2012. Thesis, Universidade Federal de Santa Maria. Accessed March 05, 2021.
http://coralx.ufsm.br/tede/tde_busca/arquivo.php?codArquivo=4151.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Griebeler, Gustavo. “CONTROLE DE QUALIDADE DE ANÁLISES DE SOLOS DA REDE ROLAS-RS/SC E PROCEDIMENTOS ESTATÍSTICOS ALTERNATIVOS.” 2012. Web. 05 Mar 2021.
Vancouver:
Griebeler G. CONTROLE DE QUALIDADE DE ANÁLISES DE SOLOS DA REDE ROLAS-RS/SC E PROCEDIMENTOS ESTATÍSTICOS ALTERNATIVOS. [Internet] [Thesis]. Universidade Federal de Santa Maria; 2012. [cited 2021 Mar 05].
Available from: http://coralx.ufsm.br/tede/tde_busca/arquivo.php?codArquivo=4151.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Griebeler G. CONTROLE DE QUALIDADE DE ANÁLISES DE SOLOS DA REDE ROLAS-RS/SC E PROCEDIMENTOS ESTATÍSTICOS ALTERNATIVOS. [Thesis]. Universidade Federal de Santa Maria; 2012. Available from: http://coralx.ufsm.br/tede/tde_busca/arquivo.php?codArquivo=4151
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Universidade Federal de Santa Maria
23.
Jean Paulo Guarnieri.
EFICIÊNCIA DOS GRÁFICOS DE CONTROLE NA DETECÇÃO DE OUTLIERS EM PROCESSOS AUTORREGRESSIVOS E DE MÉDIAS MÓVEIS.
Degree: 2010, Universidade Federal de Santa Maria
URL: http://coralx.ufsm.br/tede/tde_busca/arquivo.php?codArquivo=3510
► A presente pesquisa aborda a aplicação de modelos de previsão juntamente com a utilização de gráficos de controle de resíduos para a avaliação de processos…
(more)
▼ A presente pesquisa aborda a aplicação de modelos de previsão juntamente com a utilização de gráficos de controle de resíduos para a avaliação de processos produtivos com características de autocorrelação em suas amostras. O objetivo geral foi determinar a eficiência dos gráficos de controle de observações individuais (IMCC) e de média móvel exponencialmente ponderada (EWMA) quando aplicados aos resíduos de modelos da classe AR(1) ou MA(1), para detecção de outliers em processos autocorrelacionados, além de evidenciar a influência da autocorrelação e da amplitude do outlier no poder de detecção dos gráficos. Foram simuladas 640.000 séries para cada modelo, variando a força e o sinal da autocorrelação. Após a verificação da estabilidade dos resíduos em cada série simulada, na série original, foram inseridos outliers com amplitudes variáveis em uma observação prédeterminada. As séries contaminadas pela observação anômala foram novamente modeladas e os resíduos foram grafados em gráficos de controle IMCC e EWMA, registrando-se os pontos detectados corretamente. Em cada gráfico, para o par de variáveis: parâmetro de autocorrelação e amplitude de outlier, gerou-se uma proporção de detecção, na qual foram aplicados testes de comparação não-paramétricos. O resultado obtido por meio dos testes evidenciou a superioridade do gráfico IMCC para ambos os modelos. Quanto ao estudo da influência do parâmetro de autocorrelação, referente ao sinal e a magnitude da mesma, para ambos os gráfico e modelos AR(1) e MA(1), não se verificou diferença significativa. Dessa forma, comprovou-se a eficácia dos gráficos de controle IMCC em detectar outliers por meio de resíduos em processos industriais autocorrelacionados.
This research approaches the prediction models application along with the usage of residual control charts to evaluate productive processes with characteristics of autocorrelation in its samples. The overall objective was to determine the Individual Measurement Control Charts (IMCC) and the Exponentially Weighted Moving Average (EWMA) efficiency when applied to residuals of ARIMA class, to the outliers detection in autocorrelated processes, as well as identifying the autocorrelation influence and the amplitude of the outlier concerning the charts detection capacity. To each AR(1) and MA(1), 640.000 series were simulated, with varying strength and autocorrelation signal. After each series simulated residual stability verification, in the original series, outliers were inserted with varying amplitudes in a pre-determined observation. The series contaminated by the anomalous observation were again modeled and the residual were inscribed in IMCC and EWMA control charts, correctly registering the detected points. In the detection proportions to the outliers variant pair, autocorrelation parameter and amplitude, non parametric tests were applied. The result obtained through the tests presented the superiority of the IMCC chart for both models. To what concerns the study of the autocorrelation parameter influence, regarding its…
Advisors/Committee Members: Adriano Mendonça Souza, Roselaine Ruviaro Zanini, Luciane Flores Jacobi, Liane Werner.
Subjects/Keywords: outliers; gráficos de controle de resíduos; autocorrelação; séries temporais; ENGENHARIA DE PRODUCAO; time series; autocorrelation; residual control charts; outliers
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APA ·
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MLA ·
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CSE |
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APA (6th Edition):
Guarnieri, J. P. (2010). EFICIÊNCIA DOS GRÁFICOS DE CONTROLE NA DETECÇÃO DE OUTLIERS EM PROCESSOS AUTORREGRESSIVOS E DE MÉDIAS MÓVEIS. (Thesis). Universidade Federal de Santa Maria. Retrieved from http://coralx.ufsm.br/tede/tde_busca/arquivo.php?codArquivo=3510
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):
Guarnieri, Jean Paulo. “EFICIÊNCIA DOS GRÁFICOS DE CONTROLE NA DETECÇÃO DE OUTLIERS EM PROCESSOS AUTORREGRESSIVOS E DE MÉDIAS MÓVEIS.” 2010. Thesis, Universidade Federal de Santa Maria. Accessed March 05, 2021.
http://coralx.ufsm.br/tede/tde_busca/arquivo.php?codArquivo=3510.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Guarnieri, Jean Paulo. “EFICIÊNCIA DOS GRÁFICOS DE CONTROLE NA DETECÇÃO DE OUTLIERS EM PROCESSOS AUTORREGRESSIVOS E DE MÉDIAS MÓVEIS.” 2010. Web. 05 Mar 2021.
Vancouver:
Guarnieri JP. EFICIÊNCIA DOS GRÁFICOS DE CONTROLE NA DETECÇÃO DE OUTLIERS EM PROCESSOS AUTORREGRESSIVOS E DE MÉDIAS MÓVEIS. [Internet] [Thesis]. Universidade Federal de Santa Maria; 2010. [cited 2021 Mar 05].
Available from: http://coralx.ufsm.br/tede/tde_busca/arquivo.php?codArquivo=3510.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Guarnieri JP. EFICIÊNCIA DOS GRÁFICOS DE CONTROLE NA DETECÇÃO DE OUTLIERS EM PROCESSOS AUTORREGRESSIVOS E DE MÉDIAS MÓVEIS. [Thesis]. Universidade Federal de Santa Maria; 2010. Available from: http://coralx.ufsm.br/tede/tde_busca/arquivo.php?codArquivo=3510
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of North Texas
24.
Mitchell, Napoleon.
Outliers and Regression Models.
Degree: 1992, University of North Texas
URL: https://digital.library.unt.edu/ark:/67531/metadc279029/
► The mitigation of outliers serves to increase the strength of a relationship between variables. This study defined outliers in three different ways and used five…
(more)
▼ The mitigation of
outliers serves to increase the strength of a relationship between variables. This study defined
outliers in three different ways and used five regression procedures to describe the effects of
outliers on 50 data sets. This study also examined the relationship among the shape of the distribution, skewness, and
outliers.
Advisors/Committee Members: Brookshire, William K., Maher, Laurence P., McCallon, Earl L., Haynes, Jack Read.
Subjects/Keywords: outliers; regression models; Regression analysis.; Outliers (Statistics)
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Universidade do Rio Grande do Norte
25.
Coutinho, Maytê Duarte Leal.
Estudo do balanço de umidade por meio de modelos regionais para o clima do passado e do futuro sobre a América do Sul
.
Degree: 2015, Universidade do Rio Grande do Norte
URL: http://repositorio.ufrn.br/handle/123456789/20587
► In the context of climate change over South America (SA) has been observed that the combination of high temperatures and rain more temperatures less rainfall,…
(more)
▼ In the context of climate change over South America (SA) has been observed that the combination of high temperatures and rain more temperatures less rainfall, cause different impacts such as extreme precipitation events, favorable conditions for fires and droughts. As a result, these regions face growing threat of water shortage, local or generalized. Thus, the water availability in Brazil depends largely on the weather and its variations in different time scales. In this sense, the main objective of this research is to study the moisture budget through regional climate models (RCM) from Project Regional Climate Change Assessments for La Plata Basin (CLARIS-LPB) and combine these RCM through two statistical techniques in an attempt to improve prediction on three areas of AS: Amazon (AMZ), Northeast Brazil (NEB) and the Plata Basin (LPB) in past climates (1961-1990) and future (2071-2100). The moisture transport on AS was investigated through the moisture fluxes vertically integrated. The main results showed that the average fluxes of water vapor in the tropics (AMZ and NEB) are higher across the eastern and northern edges, thus indicating that the contributions of the trade winds of the North Atlantic and South are equally important for the entry moisture during the months of JJA and DJF. This configuration was observed in all the models and climates. In comparison climates, it was found that the convergence of the flow of moisture in the past weather was smaller in the future in various regions and seasons. Similarly, the majority of the SPC simulates the future climate, reduced precipitation in tropical regions (AMZ and NEB), and an increase in the LPB region. The second phase of this research was to carry out combination of RCM in more accurately predict precipitation, through the multiple regression techniques for components Main (C.RPC) and convex combination (C.EQM), and then analyze and compare combinations of RCM (ensemble). The results indicated that the combination was better in RPC represent precipitation observed in both climates. Since, in addition to showing values be close to those observed, the technique obtained coefficient of correlation of moderate to strong magnitude in almost every month in different climates and regions, also lower dispersion of data (RMSE). A significant advantage of the combination of methods was the ability to capture extreme events (
outliers) for the study regions. In general, it was observed that the wet C.EQM captures more extreme, while C.RPC can capture more extreme dry climates and in the three regions studied.
Advisors/Committee Members: Lima, Kellen Carla (advisor), 67048358220 (advisor), http://lattes.cnpq.br/4524628383146981 (advisor), Silva, Claudio Moisés Santos e (advisor), 66961513204 (advisor), http://lattes.cnpq.br/1394248306018449 (advisor).
Subjects/Keywords: Transporte de umidade;
Ensemble;
Modelos climáticos regionais;
Outliers
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Coutinho, M. D. L. (2015). Estudo do balanço de umidade por meio de modelos regionais para o clima do passado e do futuro sobre a América do Sul
. (Thesis). Universidade do Rio Grande do Norte. Retrieved from http://repositorio.ufrn.br/handle/123456789/20587
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):
Coutinho, Maytê Duarte Leal. “Estudo do balanço de umidade por meio de modelos regionais para o clima do passado e do futuro sobre a América do Sul
.” 2015. Thesis, Universidade do Rio Grande do Norte. Accessed March 05, 2021.
http://repositorio.ufrn.br/handle/123456789/20587.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Coutinho, Maytê Duarte Leal. “Estudo do balanço de umidade por meio de modelos regionais para o clima do passado e do futuro sobre a América do Sul
.” 2015. Web. 05 Mar 2021.
Vancouver:
Coutinho MDL. Estudo do balanço de umidade por meio de modelos regionais para o clima do passado e do futuro sobre a América do Sul
. [Internet] [Thesis]. Universidade do Rio Grande do Norte; 2015. [cited 2021 Mar 05].
Available from: http://repositorio.ufrn.br/handle/123456789/20587.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Coutinho MDL. Estudo do balanço de umidade por meio de modelos regionais para o clima do passado e do futuro sobre a América do Sul
. [Thesis]. Universidade do Rio Grande do Norte; 2015. Available from: http://repositorio.ufrn.br/handle/123456789/20587
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
26.
MOLINARES, Fabio Alexander Fajardo.
Estimação robusta em processos de memória longa na presença de outliers aditivos
.
Degree: 2007, Universidade Federal de Pernambuco
URL: http://repositorio.ufpe.br/handle/123456789/6280
► O objetivo deste trabalho é propor uma metodologia para estimar os parâmetros que indexam o processo ARFIMA(p, d, q) (Hosking 1981) na presença de outliers…
(more)
▼ O objetivo deste trabalho é propor uma metodologia para estimar os parâmetros que indexam o processo ARFIMA(p, d, q) (Hosking 1981) na presença de
outliers aditivos. Para estimar d, é proposto um estimador robusto que é uma variante do popular estimador sugerido por Geweke & Porter-Hudak (1983) (GPH). A metodologia proposta faz uso da função de autocovariância amostral robusta, considerada por Ma & Genton (2000), para obtenção do estimador da função espectral do processo. Resultados numéricos evidenciam a robustez do estimador proposto na presença de
outliers do tipo aditivo
Advisors/Committee Members: CIRABRI NETO, Francisco (advisor).
Subjects/Keywords: Robustez;
Memória longa;
Outliers
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APA ·
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APA (6th Edition):
MOLINARES, F. A. F. (2007). Estimação robusta em processos de memória longa na presença de outliers aditivos
. (Thesis). Universidade Federal de Pernambuco. Retrieved from http://repositorio.ufpe.br/handle/123456789/6280
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):
MOLINARES, Fabio Alexander Fajardo. “Estimação robusta em processos de memória longa na presença de outliers aditivos
.” 2007. Thesis, Universidade Federal de Pernambuco. Accessed March 05, 2021.
http://repositorio.ufpe.br/handle/123456789/6280.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
MOLINARES, Fabio Alexander Fajardo. “Estimação robusta em processos de memória longa na presença de outliers aditivos
.” 2007. Web. 05 Mar 2021.
Vancouver:
MOLINARES FAF. Estimação robusta em processos de memória longa na presença de outliers aditivos
. [Internet] [Thesis]. Universidade Federal de Pernambuco; 2007. [cited 2021 Mar 05].
Available from: http://repositorio.ufpe.br/handle/123456789/6280.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
MOLINARES FAF. Estimação robusta em processos de memória longa na presença de outliers aditivos
. [Thesis]. Universidade Federal de Pernambuco; 2007. Available from: http://repositorio.ufpe.br/handle/123456789/6280
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
27.
Quintas Souto Maior, Vinicius.
SYMARMA: Um modelo dinâmico para dados temporais sob distribuição simétrica condicional
.
Degree: 2012, Universidade Federal de Pernambuco
URL: http://repositorio.ufpe.br/handle/123456789/6665
► Modelos gaussianos de séries temporais ARMA têm sido largamente utilizados na literatura. Benjamin et al. (2003) estenderam estes modelos para variáveis pertencente a família de…
(more)
▼ Modelos gaussianos de séries temporais ARMA têm sido largamente utilizados na literatura.
Benjamin et al. (2003) estenderam estes modelos para variáveis pertencente a família de distribuição
exponencial. Nesta mesma linha, Rocha e Cribari-Neto (2009) propuseram um modelo
de série temporal para a classe de distribuições Beta. Nesse sentido, nós propomos o modelo
autorregressivo de médias móveis simétrico (SYMARMA), um modelo dinâmico para variáveis
aleatórias pertencentes à classe de distribuições simétricas que inclui tanto a dinâmica
autorregressiva e de média móveis, como também permite inserir regressores no modelo. O
modelo SYMARMA é construído a partir da classe de regressão simétrica só que agora, na
especificação da média, temos uma componente adicional com termos autoregressivos e de
médias móveis incluídos aditivamente. A estimação dos parâmetros do modelo SYMARMA é
feita através da maximização do logaritmo da função de verossimilhança condicional usando
um algoritmo de otimização não-linear, em particular utilizamos o algoritmo escore de Fisher.
Estudos de simulação foram realizados para avaliar o desempenho e o comportamento do estimador
de máxima verossimilhança condicional para os parâmetros do modelo e, para também
avaliar o efeito da presença de outlier aditivo ou de inovação no ajuste e na previsão de observações
futuras. Discutimos testes de hipóteses para os parâmetros do modelo. Aplicações com
dados reais também serão apresentadas e discutidas
Advisors/Committee Members: José de Azevedo Cysneiros, Francisco (advisor).
Subjects/Keywords: Séries temporais;
Previsões;
Outliers;
Máxima verossimilhança condicional;
Distribuição simétrica;
ARMA
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APA ·
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Manager
APA (6th Edition):
Quintas Souto Maior, V. (2012). SYMARMA: Um modelo dinâmico para dados temporais sob distribuição simétrica condicional
. (Thesis). Universidade Federal de Pernambuco. Retrieved from http://repositorio.ufpe.br/handle/123456789/6665
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):
Quintas Souto Maior, Vinicius. “SYMARMA: Um modelo dinâmico para dados temporais sob distribuição simétrica condicional
.” 2012. Thesis, Universidade Federal de Pernambuco. Accessed March 05, 2021.
http://repositorio.ufpe.br/handle/123456789/6665.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Quintas Souto Maior, Vinicius. “SYMARMA: Um modelo dinâmico para dados temporais sob distribuição simétrica condicional
.” 2012. Web. 05 Mar 2021.
Vancouver:
Quintas Souto Maior V. SYMARMA: Um modelo dinâmico para dados temporais sob distribuição simétrica condicional
. [Internet] [Thesis]. Universidade Federal de Pernambuco; 2012. [cited 2021 Mar 05].
Available from: http://repositorio.ufpe.br/handle/123456789/6665.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Quintas Souto Maior V. SYMARMA: Um modelo dinâmico para dados temporais sob distribuição simétrica condicional
. [Thesis]. Universidade Federal de Pernambuco; 2012. Available from: http://repositorio.ufpe.br/handle/123456789/6665
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Ryerson University
28.
Lin, Yu.
Pose estimation for robotic percussive riveting.
Degree: 2014, Ryerson University
URL: https://digital.library.ryerson.ca/islandora/object/RULA%3A3352
► Recently, a robotic percussive riveting system has been developed at Ryerson University for an automation of percussive riveting process of aero-structural fastening assembly. The system…
(more)
▼ Recently, a robotic percussive riveting system has been developed at Ryerson University for an automation of percussive riveting process of aero-structural fastening assembly. The system consists of a robot holding a percussive riveting gun equipped with a rivet feeder, a gantry holding a working panel of aero-structure, and a position visual sensor. Prior to riveting, the robot is required to first position and then insert a rivet precisely into a hole on the panel without engaging the panel to prevent potential damage. The underlying challenges to precise insertion are various sources of system uncertainties, mainly including alignment errors among coordinate systems of the robot, panel and sensor, and relatively poor absolute positioning accuracy of the robot due to mechanical deflection, assembly clearance, and machining tolerance. For this reason, the research of relative pose estimation between the robot and panel has been carried out pertaining to these challenges.
Essentially, pose estimation is proposed for robotic percussive riveting, which estimates the relative pose between two rigid bodies based on noisy visual measurements of point features on rigid bodies. Three categories can be classified, namely, static, dynamic, and robust pose estimation. Firstly, static pose estimation is the parameter estimation of static relative pose transformations among a number of frames, which solves the issue of alignment errors. Direct solutions of static relative pose estimation are derived based on least-square methods. Secondly, to tackle the issue of poor absolute positioning accuracy of the robot, dynamic relative pose estimation is proposed addressing a state estimation of relative poses during motion. Iterative extended Kalman filter method is adapted for the state estimation. Thirdly, for robustness against
outliers of point measurements, robust pose estimation is proposed based on an outlier diagnosis using the technique of relaxation of rigid body constraints. Indeed, outlier diagnosis is a pre-processing of point measurements, in which
outliers are detected and removed prior to the relative pose estimation. Further, a decorrelation method is proposed for measurement calibration using multivariate statistical analysis to find an optimal sensor-to-target configuration. As a result, each coordinate measurement is close to uncorrelated and it allows for a simple calibration.
Advisors/Committee Members: Xi, Fengfeng (Jeff) (Thesis advisor), Chan, Vincent (Thesis advisor), Ryerson University (Degree grantor).
Subjects/Keywords: Robots – Control systems.; Kalman filtering.; Outliers (Statistics); Rivets and riveting.
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APA (6th Edition):
Lin, Y. (2014). Pose estimation for robotic percussive riveting. (Thesis). Ryerson University. Retrieved from https://digital.library.ryerson.ca/islandora/object/RULA%3A3352
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):
Lin, Yu. “Pose estimation for robotic percussive riveting.” 2014. Thesis, Ryerson University. Accessed March 05, 2021.
https://digital.library.ryerson.ca/islandora/object/RULA%3A3352.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Lin, Yu. “Pose estimation for robotic percussive riveting.” 2014. Web. 05 Mar 2021.
Vancouver:
Lin Y. Pose estimation for robotic percussive riveting. [Internet] [Thesis]. Ryerson University; 2014. [cited 2021 Mar 05].
Available from: https://digital.library.ryerson.ca/islandora/object/RULA%3A3352.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Lin Y. Pose estimation for robotic percussive riveting. [Thesis]. Ryerson University; 2014. Available from: https://digital.library.ryerson.ca/islandora/object/RULA%3A3352
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Alberta
29.
Ranjan, Rishik.
Robust Gaussian Process Regression and its Application in
Data-driven Modeling and Optimization.
Degree: MS, Department of Chemical and Materials
Engineering, 2015, University of Alberta
URL: https://era.library.ualberta.ca/files/b2773z58w
► Availability of large amounts of industrial process data is allowing researchers to explore new data-based modelling methods. In this thesis, Gaussian process (GP) regression, a…
(more)
▼ Availability of large amounts of industrial process
data is allowing researchers to explore new data-based modelling
methods. In this thesis, Gaussian process (GP) regression, a
relatively new Bayesian approach to non-parametric data based
modelling is investigated in detail. One of the primary concerns
regarding the application of such methods is their sensitivity to
the presence of outlying observations. Another concern is that
their ability to predict beyond the range of observed data is often
poor which can limit their applicability. Both of these issues are
explored in this work. The problem of sensitivity to outliers is
dealt with by using a robust GP regression model. The common
approach in literature for identification of this model is to
approximate the marginal likelihood and maximize it using conjugate
gradient algorithm. In this work, an EM algorithm based approach is
proposed in which an approximate lower bound on the marginal
likelihood is iteratively maximized. Models identified using this
method are compared against those identified using conjugate
gradient method in terms of prediction performance on many
synthetic and real benchmark datasets. It is observed that the two
approaches are similar in prediction performance. However the
advantages of EM approach are numerical stability, ease of
implementation and theoretical guarantee of convergence. The
application of proposed robust GP regression in chemical
engineering is also explored. An optimization problem for an
industrial water treatment and steam generation network is
formulated. Process models are constructed using material balance
equations and used for data reconciliation and steady state
optimization of the cost of steam production. Since the overall
network is under manual operation, a dynamic optimization framework
is constructed to find a set point change strategy which operators
can use for minimizing steam production cost. Dynamic models for
process units and tanks are integrated into this framework. Some of
these models are identified using proposed robust GP regression
method. Extrapolation ability of identified GP models is improved
by applying a suitable GP kernel structure and by using some ad hoc
scaling techniques. Based on the application of robust GP
regression to an industrial optimization problem, it is shown that
non-parametric data-based modelling can be successfully integrated
with process optimization objectives.
Subjects/Keywords: SAGD; Optimization; Outliers; Robust identification; Gaussian process regression; EM algorithm
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APA ·
Chicago ·
MLA ·
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CSE |
Export
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APA (6th Edition):
Ranjan, R. (2015). Robust Gaussian Process Regression and its Application in
Data-driven Modeling and Optimization. (Masters Thesis). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/b2773z58w
Chicago Manual of Style (16th Edition):
Ranjan, Rishik. “Robust Gaussian Process Regression and its Application in
Data-driven Modeling and Optimization.” 2015. Masters Thesis, University of Alberta. Accessed March 05, 2021.
https://era.library.ualberta.ca/files/b2773z58w.
MLA Handbook (7th Edition):
Ranjan, Rishik. “Robust Gaussian Process Regression and its Application in
Data-driven Modeling and Optimization.” 2015. Web. 05 Mar 2021.
Vancouver:
Ranjan R. Robust Gaussian Process Regression and its Application in
Data-driven Modeling and Optimization. [Internet] [Masters thesis]. University of Alberta; 2015. [cited 2021 Mar 05].
Available from: https://era.library.ualberta.ca/files/b2773z58w.
Council of Science Editors:
Ranjan R. Robust Gaussian Process Regression and its Application in
Data-driven Modeling and Optimization. [Masters Thesis]. University of Alberta; 2015. Available from: https://era.library.ualberta.ca/files/b2773z58w
30.
TÃnia Miranda Nepomucena.
AplicaÃÃo da estratÃgia de alocaÃÃo nÃo proporcional para identificar outliers em dados binomiais.
Degree: 2009, UNIVERSIDADE FEDERAL DE LAVRAS
URL: http://bibtede.ufla.br/tede//tde_busca/arquivo.php?codArquivo=1983
► O mÃtodo de anÃlise robusta de variÃncia que à apresentado, permite monitorar o efeito dos outliers por meio da estratÃgia nÃo-proporcional. Para isso, utiliza-se a…
(more)
▼ O mÃtodo de anÃlise robusta de variÃncia que à apresentado, permite monitorar o efeito dos outliers por meio da estratÃgia nÃo-proporcional. Para isso, utiliza-se a formaÃÃo de subconjuntos, nos quais, as unidades amostrais sÃo alocadas, baseando-se em apenas uma inspeÃÃo nos dados. Com o propÃsito de estender esse mÃtodo para o modelo binomial, este trabalho propÃe identificar outliers em dados de proporÃÃo com a aplicaÃÃo da estratÃgia nÃo-proporcional. Os dados utilizados sÃo provenientes de um experimento realizado no LaboratÃrio de Biologia do Departamento de Entomologia da ESALQ/USP. Foi implementado um algoritmo de uso no programa estatÃstico R para formaÃÃo de subconjuntos previstos pelo mÃtodo em estudo. Utilizando a funÃÃo glm do programa R, estimou-se pelo mÃtodo da mÃxima verossimilhanÃa parÃmetros do modelo binomial com as funÃÃes de ligaÃÃo logit, probit e complemento log-log, tambÃm foram computados a deviance, os preditores lineares e os valores esperados dos modelos ajustados. A discussÃo em torno dos resultados foi realizada com base nos grÃficos construÃdos. As estimativas dos parÃmetros do modelo diferiram entre as funÃÃes de ligaÃÃo. Para modelos diferentes, os preditores lineares apresentaram valores de magnitudes muito prÃximas. Observou-se que mesmo para funÃÃes de ligaÃÃo distintas, os outliers podem ser monitorados. Isto exposto, concluiu-se que a metodologia proposta neste trabalho à viÃvel e recomendÃvel, podendo ser estendida para outros modelos pertencentes à classe de modelos lineares generalizados, sendo portanto, uma importante tÃcnica de anÃlise de dados para se detectar a presenÃa de outliers.
The method of robust analysis of variance that is displayed, allows monitoring the effect of outliers by the non-proportional strategy . To do this, using the formation of subsets, in which the sample units are allocated, based on one inspection to the data. With the aim of extending this method to the binomial model, this work proposes identify outliers in data of proportion with the application of the non-proportional strategy. The data used are from an experiment conducted in the Biology Laboratory, Department of Entomology of ESALQ / USP. An algorithm was implemented for use in the statistical program R to subsets provided by the method of study. Using the function glm in program R, was estimated by the method of maximum likelihood parameters of the binomial model with logit link-function, probit and complementary log-log, were also computed the deviance, the linear predictors and expected values of the adjusted models . The discussion around the results was based on graphs. Estimates of the parameters of the model differ between the link functions. For different models, the linear predictors had very similar values of magnitudes. It was observed that even for different link functions, the outliers can be monitored. This exposed, it was concluded that the methodology proposed in this paper is feasible and advisable, and may be extended to other models belonging to the class of…
Advisors/Committee Members: Thelma SÃfadi, Renato Ribeiro de Lima, Marcelo Ãngelo Cirillo, Carla Regina GuimarÃes Brighenti.
Subjects/Keywords: FunÃÃes de ligaÃÃo; AGRONOMIA; Outliers; EstratÃgia nÃo-proporcional; Modelo binomial
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APA ·
Chicago ·
MLA ·
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to Zotero / EndNote / Reference
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APA (6th Edition):
Nepomucena, T. M. (2009). AplicaÃÃo da estratÃgia de alocaÃÃo nÃo proporcional para identificar outliers em dados binomiais. (Thesis). UNIVERSIDADE FEDERAL DE LAVRAS. Retrieved from http://bibtede.ufla.br/tede//tde_busca/arquivo.php?codArquivo=1983
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):
Nepomucena, TÃnia Miranda. “AplicaÃÃo da estratÃgia de alocaÃÃo nÃo proporcional para identificar outliers em dados binomiais.” 2009. Thesis, UNIVERSIDADE FEDERAL DE LAVRAS. Accessed March 05, 2021.
http://bibtede.ufla.br/tede//tde_busca/arquivo.php?codArquivo=1983.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Nepomucena, TÃnia Miranda. “AplicaÃÃo da estratÃgia de alocaÃÃo nÃo proporcional para identificar outliers em dados binomiais.” 2009. Web. 05 Mar 2021.
Vancouver:
Nepomucena TM. AplicaÃÃo da estratÃgia de alocaÃÃo nÃo proporcional para identificar outliers em dados binomiais. [Internet] [Thesis]. UNIVERSIDADE FEDERAL DE LAVRAS; 2009. [cited 2021 Mar 05].
Available from: http://bibtede.ufla.br/tede//tde_busca/arquivo.php?codArquivo=1983.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Nepomucena TM. AplicaÃÃo da estratÃgia de alocaÃÃo nÃo proporcional para identificar outliers em dados binomiais. [Thesis]. UNIVERSIDADE FEDERAL DE LAVRAS; 2009. Available from: http://bibtede.ufla.br/tede//tde_busca/arquivo.php?codArquivo=1983
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
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Open Access Theses and Dissertations