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You searched for subject:(ROI size). Showing records 1 – 3 of 3 total matches.

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University of Ottawa

1. Olorunnimbe, Muhammed. Intelligent Adaptation of Ensemble Size in Data Streams Using Online Bagging .

Degree: 2015, University of Ottawa

In this era of the Internet of Things and Big Data, a proliferation of connected devices continuously produce massive amounts of fast evolving streaming data. There is a need to study the relationships in such streams for analytic applications, such as network intrusion detection, fraud detection and financial forecasting, amongst other. In this setting, it is crucial to create data mining algorithms that are able to seamlessly adapt to temporal changes in data characteristics that occur in data streams. These changes are called concept drifts. The resultant models produced by such algorithms should not only be highly accurate and be able to swiftly adapt to changes. Rather, the data mining techniques should also be fast, scalable, and efficient in terms of resource allocation. It then becomes important to consider issues such as storage space needs and memory utilization. This is especially relevant when we aim to build personalized, near-instant models in a Big Data setting. This research work focuses on mining in a data stream with concept drift, using an online bagging method, with consideration to the memory utilization. Our aim is to take an adaptive approach to resource allocation during the mining process. Specifically, we consider metalearning, where the models of multiple classifiers are combined into an ensemble, has been very successful when building accurate models against data streams. However, little work has been done to explore the interplay between accuracy, efficiency and utility. This research focuses on this issue. We introduce an adaptive metalearning algorithm that takes advantage of the memory utilization cost of concept drift, in order to vary the ensemble size during the data mining process. We aim to minimize the memory usage, while maintaining highly accurate models with a high utility. We evaluated our method against a number of benchmarking datasets and compare our results against the state-of-the art. Return on Investment (ROI) was used to evaluate the gain in performance in terms of accuracy, in contrast to the time and memory invested. We aimed to achieve high ROI without compromising on the accuracy of the result. Our experimental results indicate that we achieved this goal.

Subjects/Keywords: Data stream; Concept drift; Metalearning; Cost sensitive adaptation; ROI; Utility; Adaptive ensemble size; Online bagging

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Olorunnimbe, M. (2015). Intelligent Adaptation of Ensemble Size in Data Streams Using Online Bagging . (Thesis). University of Ottawa. Retrieved from http://hdl.handle.net/10393/32340

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):

Olorunnimbe, Muhammed. “Intelligent Adaptation of Ensemble Size in Data Streams Using Online Bagging .” 2015. Thesis, University of Ottawa. Accessed November 20, 2019. http://hdl.handle.net/10393/32340.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Olorunnimbe, Muhammed. “Intelligent Adaptation of Ensemble Size in Data Streams Using Online Bagging .” 2015. Web. 20 Nov 2019.

Vancouver:

Olorunnimbe M. Intelligent Adaptation of Ensemble Size in Data Streams Using Online Bagging . [Internet] [Thesis]. University of Ottawa; 2015. [cited 2019 Nov 20]. Available from: http://hdl.handle.net/10393/32340.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Olorunnimbe M. Intelligent Adaptation of Ensemble Size in Data Streams Using Online Bagging . [Thesis]. University of Ottawa; 2015. Available from: http://hdl.handle.net/10393/32340

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


Freie Universität Berlin

2. Sachs, Johanna Sabine. Analysis of signalintensity-time- curves in contrastmedia enhanced breast mri.

Degree: 2010, Freie Universität Berlin

The advantages of contrast media-enhanced breast MRI are well known. In routine clinical practice the contrast enhancing regions of interest (ROI) are chosen manually, which causes variations of the characteristic kinetic curves and their interpretation. This study aims to increase reproducibility of the characteristic kinetic curves by semi-automated ROI-placement. It is investigated by ROC-analysis which parameter describes the curves best and which size of semi-automated ROI is necessary to distinguish between benign and malignant breast lesions. The database consists of 121 patients, which underwent mamma-MRI. The standardized parameters “washout” and “integrated” have shown best results. Semi-automated ROI, containing 5, 25 and 37 Pixel, appear to be equal to a manually chosen ROI. We conclude that parametric description and use of semi-automated ROI can help with the interpretation of contrast enhancing lesions. Advisors/Committee Members: w (gender), Prof. Dr. med. U. Bick (firstReferee), Prof. Dr. med. W. Heindel, Prof. Dr. med. U. Fischer (furtherReferee).

Subjects/Keywords: Dynamic contrast media-enhanced breast mri; characteristic kinetic curve; ROI size; 600 Technik, Medizin, angewandte Wissenschaften::610 Medizin und Gesundheit

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Sachs, J. S. (2010). Analysis of signalintensity-time- curves in contrastmedia enhanced breast mri. (Thesis). Freie Universität Berlin. Retrieved from http://dx.doi.org/10.17169/refubium-9988

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):

Sachs, Johanna Sabine. “Analysis of signalintensity-time- curves in contrastmedia enhanced breast mri.” 2010. Thesis, Freie Universität Berlin. Accessed November 20, 2019. http://dx.doi.org/10.17169/refubium-9988.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Sachs, Johanna Sabine. “Analysis of signalintensity-time- curves in contrastmedia enhanced breast mri.” 2010. Web. 20 Nov 2019.

Vancouver:

Sachs JS. Analysis of signalintensity-time- curves in contrastmedia enhanced breast mri. [Internet] [Thesis]. Freie Universität Berlin; 2010. [cited 2019 Nov 20]. Available from: http://dx.doi.org/10.17169/refubium-9988.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Sachs JS. Analysis of signalintensity-time- curves in contrastmedia enhanced breast mri. [Thesis]. Freie Universität Berlin; 2010. Available from: http://dx.doi.org/10.17169/refubium-9988

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

3. Thiel, Kristen Marie. Essays on Protected Area Size: Effects on Ecological and Economic Effectiveness.

Degree: MS, Agricultural Economics, 2017, University of Tennessee – Knoxville

Faced with continuing threats to biodiversity, governments are increasingly seeking to expand protected areas. Financial resources are limited, which often spurs conservation planners to prioritize locations for future protection. Thus, prioritization of protected areas is increasingly being evaluated based on the return on investment (ROI) they offer. This thesis consists of two essays analyzing the land acquisitions made by the world’s largest conservation organization, The Nature Conservancy (TNC). In the first essay, entitled “Effects of Protected Area Size on Conservation Return on Investment,” the increase in effective mesh size per dollar invested to acquire a parcel was greater for larger parcels, implying that the overall ecological and economic effectiveness is higher in protecting larger areas relative to smaller ones. This finding suggests that, all else being equal, conservation organizations have an incentive when selecting parcels for protected area creation to favor larger parcels over smaller ones. Furthermore, given the incentive to favor larger parcels, conservation organizations tend to favor larger parcels more as is the case when they focus on both ecological and economic effectiveness together and not on ecological effectiveness alone. Therefore, a conservation priority decision will be biased toward larger parcels if conservation organizations are interested in achieving ecological and economic effectiveness. The second essay, entitled “Effects of Parcel Size on Conservation Return on Investment for Protected and Unprotected Matching Sites,” provides the first rigorous test of and comparison of the elasticity of size on conservation ROI with area between transactions made by a conservation organization versus transactions without such involvement. This comparison shows that a conservation organization’s scale effects with protected area size on conservation benefit and cost are not shown in non-conservation acquisitions in the wider land market. This finding implies that different preferences lead to scale effects with protected area size on conservation benefit and cost as the general market behavior of the non-conservation buyers does not result in the same scale effects for unprotected sites. Advisors/Committee Members: Seong-Hoon Cho, Paul R. Armsworth, Donald G. Hodges.

Subjects/Keywords: Return on Investment; ROI; conservation; protected area; size; Agricultural Economics

…37 Figure 2.2 Empirical Results – ROI Regressed on Protected Area Size… …have explicitly focused on the role of protected area size on conservation ROI specifically… …the role of protected area size on conservation ROI to combine benefit and cost measurements… …component of conservation ROI, and (4) the role of protected area size in determining… …protected area size on predicted ROI. Here, predicted ROI was used instead of observed ROI based… 

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Thiel, K. M. (2017). Essays on Protected Area Size: Effects on Ecological and Economic Effectiveness. (Thesis). University of Tennessee – Knoxville. Retrieved from https://trace.tennessee.edu/utk_gradthes/4782

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):

Thiel, Kristen Marie. “Essays on Protected Area Size: Effects on Ecological and Economic Effectiveness.” 2017. Thesis, University of Tennessee – Knoxville. Accessed November 20, 2019. https://trace.tennessee.edu/utk_gradthes/4782.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Thiel, Kristen Marie. “Essays on Protected Area Size: Effects on Ecological and Economic Effectiveness.” 2017. Web. 20 Nov 2019.

Vancouver:

Thiel KM. Essays on Protected Area Size: Effects on Ecological and Economic Effectiveness. [Internet] [Thesis]. University of Tennessee – Knoxville; 2017. [cited 2019 Nov 20]. Available from: https://trace.tennessee.edu/utk_gradthes/4782.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Thiel KM. Essays on Protected Area Size: Effects on Ecological and Economic Effectiveness. [Thesis]. University of Tennessee – Knoxville; 2017. Available from: https://trace.tennessee.edu/utk_gradthes/4782

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

.