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Influence of Underlying Random Walk Types in Population Models on Resulting Social Network Types and Epidemiological DynamicsKolgushev, Oleg 12 1900 (has links)
Epidemiologists rely on human interaction networks for determining states and dynamics of disease propagations in populations. However, such networks are empirical snapshots of the past. It will greatly benefit if human interaction networks are statistically predicted and dynamically created while an epidemic is in progress. We develop an application framework for the generation of human interaction networks and running epidemiological processes utilizing research on human mobility patterns and agent-based modeling. The interaction networks are dynamically constructed by incorporating different types of Random Walks and human rules of engagements. We explore the characteristics of the created network and compare them with the known theoretical and empirical graphs. The dependencies of epidemic dynamics and their outcomes on patterns and parameters of human motion and motives are encountered and presented through this research. This work specifically describes how the types and parameters of random walks define properties of generated graphs. We show that some configurations of the system of agents in random walk can produce network topologies with properties similar to small-world networks. Our goal is to find sets of mobility patterns that lead to empirical-like networks. The possibility of phase transitions in the graphs due to changes in the parameterization of agent walks is the focus of this research as this knowledge can lead to the possibility of disruptions to disease diffusions in populations. This research shall facilitate work of public health researchers to predict the magnitude of an epidemic and estimate resources required for mitigation.
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Ecological correlates of the abundance of juvenile green sea turtles (Chelonia Mydas) on nearshore reefs in southeast FloridaUnknown Date (has links)
Juvenile green turtle (Chelonia mydas) abundance differs among nearshore reefs,
but why some sites are preferred over others is unknown. My study had two objectives:
to quantify differences in abundance over time (one year) and to determine what
ecological factors were correlated with those differences. I conducted quarterly surveys
on reefs in Palm Beach and Broward Counties and compared reef sites with respect to (i)
water depth, (ii) algal abundance and composition, and (iii) changes in reef area (caused
by sand covering) through time (11 years). Turtles were most abundant on shallow reefs
exposed to high light levels that remained stable (uncovered by sand) for long periods of
time. These reefs had the highest diversity of algal species, in part because cropping by
the turtles prevented any one species from becoming dominant. My results suggest that
both physical and biological factors make some reefs more attractive to turtles than
others / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2013.
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Sensitivity analysis of predictive data analytic models to attributesUnknown Date (has links)
Classification algorithms represent a rich set of tools, which train a classification model from a given training and test set, to classify previously unseen test instances. Although existing methods have studied classification algorithm performance with respect to feature selection, noise condition, and sample distributions, our existing studies have not addressed an important issue on the classification algorithm performance relating to feature deletion and addition. In this thesis, we carry out sensitive study of classification algorithms by using feature deletion and addition. Three types of classifiers: (1) weak classifiers; (2) generic and strong classifiers; and (3) ensemble classifiers are validated on three types of data (1) feature dimension data, (2) gene expression data and (3) biomedical document data. In the experiments, we continuously add redundant features to the training and test set in order to observe the classification algorithm performance, and also continuously remove features to find the performance of the underlying
classifiers. Our studies draw a number of important findings, which will help data mining and machine learning community under the genuine performance of common classification algorithms on real-world data. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
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Risk-evaluation in clinical diagnostic studies: ascertaining statistical bounds via logistic regression of medical informatics dataUnknown Date (has links)
The efforts addressed in this thesis refer to applying nonlinear risk predictive techniques based on logistic regression to medical diagnostic test data. This study is motivated and pursued to address the following: 1. To extend logistic regression model of biostatistics to medical informatics 2. Computational preemptive and predictive testing to determine the probability of occurrence (p) of an event by fitting a data set to a (logit function) logistic curve: Finding upper and lower bounds on p based on stochastical considerations 3. Using the model developed on available (clinical) data to illustrate the bounds-limited performance of the prediction. Relevant analytical methods, computational efforts and simulated results are presented. Using the results compiled, the risk evaluation in medical diagnostics is discussed with real-world examples. Conclusions are enumerated and inferences are made with directions for future studies. / by Alice Horn Dupont. / Thesis (M.S.C.S.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.
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Hybrid model for optimization of cost operations for a university transit serviceUnknown Date (has links)
The demand on transportation infrastructure is dramatically increasing due to population growth causing the transportation systems to be pushed to their limits. With the projected population growth, not only for the U.S. but especially for the higher education field, university campuses are of great importance for transportation engineers. Urban univeristy campuses are considered major trip generators and with the population forecast many challenges are bound to arise. The implementation of an improved transit system provides a lower-cost solution to the continuously increasing congestion problems in university campus road networks and surrounding areas. This paper presents a methodology focused on the development of a hybrid system concentrated in three main aspects of transit functionality : access to bus stop location, reasonable travel time and low cost. Two methods for bus stop locations assessment are presented for two levels of analysis : microscopic and mesoscopic. The resulting travel time from the improved bus stop locations is analyzed and compared to the initial conditions by using a microsimulation platform. The development of a mathematical model targets the overall system's cost minimization, including user and operator cost, while maximizing the service coverage. The results demonstrate the benefits of the bus stop assessment by the two applied methods, as well as, the benefits of the route and headway selection based on the mathematical model. Moreover, the results indicate that the generation of routes using travel time as the impedance factor generates the optimal possible routes to obtain the minimum system's overall cost. / by Alicia Benazir Portal Palomo. / Thesis (M.S.C.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2012. Mode of access: World Wide Web.
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Bootstrap standard error and confidence intervals for the correlation corrected for indirect range restriction: a Monte Carlo study. / Bootstrap method / Bootstrap standard error & confidence intervals for the correlation corrected for indirect range restrictionJanuary 2006 (has links)
Li Johnson Ching Hong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 40-42). / Abstracts in English and Chinese. / ACKNOWLEDGEMENT --- p.2 / ABSTRACT --- p.3 / CHINESE ABSTRACT --- p.4 / TABLE OF CONTENTS --- p.5 / Chapter CHAPTER 1 --- INTRODUCTION --- p.7 / Thorndike's Three Formulae to Correct Correlation for Range Restriction --- p.8 / Significance of Case 3 --- p.9 / Importance of Standard Error and Confidence Intervals --- p.10 / Research Gap in the Estimation of Standard Error of rc and the Construction of the Confidence Intervals for pxy --- p.10 / Objectives of the Present Study --- p.12 / Chapter CHAPTER 2 --- BOOTSTRAP METHOD --- p.13 / Different Confidence Intervals Constructed for the Present Study --- p.14 / Chapter CHAPTER 3 --- A PROPOSED PROCEDURE FOR THE ESTIMATION OF STANDAR ERROR OF rc AND THE CONSTRUCTION OF CONFIDENCE INTERVALS --- p.16 / Chapter CHAPTER 4 --- METHODS --- p.20 / Model Specifications --- p.20 / Procedure --- p.21 / Chapter CHAPTER 5 --- ASSESSMENT --- p.23 / Chapter CHAPTER 6 --- RESULTS --- p.25 / Accuracy of Average Correlation Corrected for IRR ( rc ) --- p.25 / Empirical Standard Deviation (SDE) of rc --- p.29 / Accuracy of Standard Error Estimate --- p.29 / Accuracy of Confidence Intervals --- p.33 / Chapter CHAPTER 7 --- DISCUSSION AND CONCLUSION --- p.36 / Chapter CHAPTER 8 --- LIMITATIONS AND FURTHER DIRECTIONS --- p.38 / REFERENCES --- p.40 / APPENDIX A --- p.43 / FIGURE CAPTION --- p.53 / LIST OF TABLES --- p.55
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On the regression model with count data: with application in air pollution data.January 1999 (has links)
by Kwok-Fai Mo. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 74-79). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Statistical Modeling --- p.5 / Chapter 2.1 --- Poisson Regression --- p.5 / Chapter 2.2 --- Overdispersion and Autorrelation --- p.7 / Chapter 2.3 --- Generalized Estimating Equation --- p.9 / Chapter 2.4 --- Zeger's Mehthod --- p.12 / Chapter 2.5 --- Multicollinearity --- p.18 / Chapter 2.5.1 --- The Modified Generalized Estimating Equation --- p.18 / Chapter 2.6 --- Bootstrapping Method --- p.21 / Chapter 2.7 --- The Bootstrap Choice of Ridge Parameter --- p.23 / Chapter 3 --- The Robustness of Zeger's Approach to the Specification of ηt - Simulation Study --- p.26 / Chapter 3.1 --- Introduction --- p.26 / Chapter 3.2 --- Zeger's Algorithm with Varoious Time Series Data --- p.27 / Chapter 3.2.1 --- Data without Multicollinearity --- p.27 / Chapter 3.2.1 --- Data with Multicollinearity --- p.34 / Chapter 3.3 --- Modified Generalized Estimating Equation Approach --- p.40 / Chapter 3.3 --- The Choice of Ridge Paramter in Bootstrap --- p.42 / Chapter 4 --- Real Example --- p.46 / Chapter 4.1 --- Data Structure --- p.46 / Chapter 4.2 --- Model Building --- p.49 / Chapter 4.3 --- Single Pollutant Model --- p.57 / Chapter 4.4 --- Multiple Pollutant Model --- p.62 / Chapter 5 --- Conclusion and Discussion --- p.64 / Appendix --- p.69 / References --- p.74
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Agent-based models of complex adaptive systems. / 複雜適應系統中的個體為本模型 / Agent-based models of complex adaptive systems. / Fu za shi ying xi tong zhong de ge ti wei ben mo xingJanuary 2000 (has links)
by Lo Ting Shek = 複雜適應系統中的個體為本模型 / 盧庭碩. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 105-107). / Text in English; abstracts in English and Chinese. / by Lo Ting Shek = Fu za shi ying xi tong zhong de ge ti wei ben mo xing / Lu Tingshuo. / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Minority game --- p.9 / Chapter 2.1 --- The model --- p.9 / Chapter 2.2 --- Review on selected work on MG --- p.13 / Chapter 2.2.1 --- Market efficiency and Phase transition --- p.13 / Chapter 2.2.2 --- Crowd effect in MG --- p.17 / Chapter 2.2.3 --- Hamming distance between strategies --- p.19 / Chapter 2.2.4 --- Statistical mechanics of systems with heterogeneous agents --- p.21 / Chapter 3 --- Theory of the minority game --- p.23 / Chapter 3.1 --- Formalism --- p.23 / Chapter 3.2 --- Discussion --- p.31 / Chapter 4 --- Evolutionary Minority Game --- p.33 / Chapter 4.1 --- Model --- p.33 / Chapter 4.2 --- Results --- p.36 / Chapter 4.3 --- Discussion --- p.38 / Chapter 5 --- Theory of the Evolutionary Minority game --- p.43 / Chapter 5.1 --- The theory of D'hulst and Rodgers [1] --- p.44 / Chapter 5.1.1 --- Discussion on the D'hulst and Rodgers's theory --- p.51 / Chapter 5.2 --- Theory of EMG [2] --- p.54 / Chapter 5.2.1 --- Formalism --- p.55 / Chapter 5.2.2 --- Results --- p.60 / Chapter 5.2.3 --- Discussion --- p.66 / Chapter 6 --- Evolutionary Minority Game with arbitrary cutoffs --- p.68 / Chapter 6.1 --- Model --- p.68 / Chapter 6.2 --- Results --- p.69 / Chapter 6.3 --- Theory --- p.76 / Chapter 6.4 --- Discussion --- p.85 / Chapter 7 --- Evolutionary minority game with heterogeneous strategy distribution --- p.88 / Chapter 7.1 --- Model --- p.89 / Chapter 7.2 --- Results --- p.90 / Chapter 7.3 --- Discussion --- p.99 / Chapter 8 --- Conclusion --- p.103
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Non-elite mortuary variability in the Early Dynastic Memphis regionJanulíková, Barbora January 2018 (has links)
No settlement remains at Early Dynastic Memphis, the first ‘capital’ of the newly emerging Egyptian state, have yet been located. This study draws together exclusive evidence from three well-known non-elite Memphite cemeteries Saqqara-Serapeum, Turah and the recently excavated site of Helwan (all dating from 3200 to 2700 BC) to explore the society of this early urban centre through its funerary remains. The study engages in statistical analyses of cemetery data comparing grave parameters such as volume, quantity of grave goods, their materials and pottery vessel types, but also architecture, body protection, skeletal sex and the age of the deceased across sites. The application of statistical hypothesis testing techniques forms a methodological cornerstone highlighting some pitfalls of mortuary analyses rooted in Processual theoretical frameworks. As a result, a nuanced funerary culture with a significant degree of mortuary variability was revealed at each of the sites investigated. Non-elite funerary provision at Memphis was influenced by a complex web of factors such as economic potential, relationships to local elites, communal and personal identities, choice, and practicality. While mortuary differentiation by sex could not be proven statistically, evidence emerged for significant age differentiation in the funerary provision. The four communities investigated are distinct and each represent a different population within the Memphite region ranging from a main necropolis (Helwan) to a cemetery of a secondary or tertiary local centre (Turah). The smallscale regionality observed at Memphis should serve as a springboard for future research on Early Dynastic Egypt. Finally, the study has highlighted the research potential of statistical analyses to extract vital information from old data, alongside the importance of hypothesis testing in the evaluation of such analyses.
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On the analysis of multiple informant data: a Monte Carlo comparison. / CUHK electronic theses & dissertations collectionJanuary 2013 (has links)
Cheung, Yu Hin Ray. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 59-66). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese.
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