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Articles 5101 - 5130 of 12832
Full-Text Articles in Statistics and Probability
Impact Of Agreeableness On Virtual Team Performance Through Team Identification And Shared Mental Models, Alexandria Brown
Impact Of Agreeableness On Virtual Team Performance Through Team Identification And Shared Mental Models, Alexandria Brown
Graduate Research Theses & Dissertations
Virtual teams help organizations efficiently utilize their employees for a task without the requirement of co-location. The literature on team performance suggests that teamwork is integral to a team’s success; however, in virtual teams this is often a challenge. Certain personality characteristics on virtual teams may be particularly important to the development of effective teamwork. An under-investigated factor is the role agreeableness in virtual team processes and how it affects the overall team performance. The main research question of this study is how the degree of agreeableness on a virtual team affects the overall team performance through predicted associations with …
Maximum Likelihood Estimation For A Heavy-Tailed Mixture Distribution, Philippe Kponbogan Dovoedo
Maximum Likelihood Estimation For A Heavy-Tailed Mixture Distribution, Philippe Kponbogan Dovoedo
Graduate Research Theses & Dissertations
In an increasingly connected global environment, “high-impact, low-probability" (HILP)
events can have devastating consequences and result in large insurance losses with a heavy-
tailed distribution. Examples of such events include Hurricane Katrina, the Deepwater
Horizon oil disaster and the Japanese nuclear crisis and tsunami. According to the 2012
Blackett Review of HILP Risks from the UK Government Office for Science, the
identification of low-probability risks, and the subsequent development of mitigation plans,
is complicated by their rare or conjectural nature, and their potential for causing impacts
beyond everyday experience. Extremal mixture models and more generally extreme value
analysis help assess …
Bivariate Cure Rate Model Using Copula Functions In Presence Of Censored Data And Covariates, Jie Huang
Bivariate Cure Rate Model Using Copula Functions In Presence Of Censored Data And Covariates, Jie Huang
Graduate Research Theses & Dissertations
Bivariate survival cure rate models extend the understanding of time-to-event data by allowing for the formulation of more accurate and informative conclusion. These conclusions are obtainable from an analysis that accounts for a cured fraction of the population and dependence between paired units. We propose a mixture cure rate model where a correlation coefficient is used for the association between bivariate cure rate fractions and a new generalized Farlie Gumbel Morgenstern (FGM) copula function is applied to model the de-
pendence structure of bivariate survival times. Covariate effects are incorporated into two components of our model, cure rate fractions and …
Evaluation Of Epilepsy Surgery Using Bayesian Multinomial Regression, Kacy Danielle Kane
Evaluation Of Epilepsy Surgery Using Bayesian Multinomial Regression, Kacy Danielle Kane
Graduate Research Theses & Dissertations
We are exploring the effectiveness of brain surgeries that are supposed to eliminate or reduce the frequency of seizures in young Epilepsy patients. The long-term effectiveness of brain surgeries is evaluated by ordinal categories and brings longitudinal categorical responses.
Using a Bayesian multinomial regression model we examine the responses by the lobe of brain and other covariates as well as time. To overcome computational difficulties we utilize latent variables for multinomial responses and compare the results with frequentists methods.
Bayesian Lasso Survival Analysis, Justin P. Neely
Bayesian Lasso Survival Analysis, Justin P. Neely
Graduate Research Theses & Dissertations
This thesis examines the use of Bayesian LASSO regression for survival data to estimate the survival function and to select significant covariates simultaneously. We consider survival times of patients with adenocarcinoma lung cancer. The survival and genetic data are available in the Cancer Genome Atlas (TCGA) Research Network. As a pilot study, within chromosome 5, we apply Bayesian LASSO regression to explore genetic markers that may help to identify crucial genes to determine survival times of patients. Using Gibbs sampling we can obtain Markov Chain Monte Carlo samples for regression coefficients and model variance as well as LASSO penalty from …
Applications Of Bayesian Functional Data Analysis, Hao Shen
Applications Of Bayesian Functional Data Analysis, Hao Shen
Graduate Research Theses & Dissertations
Functional Data Analysis (FDA) is a set of statistical methods that can deal with the data which represent curves or functions. In this dissertation, we consider two extensions of FDA to two types of data, circadian data and multidimensional data. The first part of the dissertation is concerned with the analysis of circadian data. We estimate circadian functions by using Bayesian smoothing splines under the generalized linear model, and extract two measures from each estimated function, magnitude and roughness. Based on extracted measures, we cluster individual functions into normal group and abnormal group by utilizing a density based clustering method. …
A Statistical Analysis And Machine Learning Of Genomic Data, Jongyun Jung
A Statistical Analysis And Machine Learning Of Genomic Data, Jongyun Jung
All Graduate Theses, Dissertations, and Other Capstone Projects
Machine learning enables a computer to learn a relationship between two assumingly related types of information. One type of information could thus be used to predict any lack of informaion in the other using the learned relationship. During the last decades, it has become cheaper to collect biological information, which has resulted in increasingly large amounts of data. Biological information such as DNA is currently analyzed by a variety of tools. Although machine learning has already been used in various projects, a flexible tool for analyzing generic biological challenges has not yet been made. The recent advancements in the DNA …
Adaptive Smoothing Parameter In Kernel Density Estimation And Parameter Estimation In Normal Mixture Distributions, Sabiha Mahzabeen
Adaptive Smoothing Parameter In Kernel Density Estimation And Parameter Estimation In Normal Mixture Distributions, Sabiha Mahzabeen
All Graduate Theses, Dissertations, and Other Capstone Projects
Kernel density estimation is a widely used tool in nonparametric density estimation procedures. Choice of a kernel function and a smoothing parameter are two important issues in implementing kernel density estimation procedures. In this paper, four different kernel functions are considered in implementing an adaptive selection procedure in choosing the smoothing parameter. In simulation, a skewed bimodal density which is a mixture of two normal distributions is considered along with the standard normal and the standard exponential densities. In skewed bimodal data, parameter estimation is also explored in the context of the parameter estimation in mixtures of normal distributions. Maximum …
A Geographic Study Of Lung And Bronchus Cancer Rates In Kentucky, Gabriel Njoh Dikong
A Geographic Study Of Lung And Bronchus Cancer Rates In Kentucky, Gabriel Njoh Dikong
Walden Dissertations and Doctoral Studies
The average age-adjusted incidence and mortality rates of lung and bronchus cancer is 55% and 56% higher in Kentucky than the national averages in the United States, respectively. Populations with low income and educational attainment, and those who live close to the mining regions across Kentucky are more affected by the high prevalence and resulting mortality rates of lung and bronchus cancer. This study was conducted because of the high incidence of lung and bronchus cancer and resulting mortality rates in the state of Kentucky that may not be caused solely by social and demographic factors. The theoretical foundation for …
The Exponentiated Generalized Topp Leone-G Family Of Distributions: Properties And Applications, Hesham Mohammed Reyad, Morad Alizadeh, Farrukh Jamal, Soha Othman, Gholamhossein G. Hamedani
The Exponentiated Generalized Topp Leone-G Family Of Distributions: Properties And Applications, Hesham Mohammed Reyad, Morad Alizadeh, Farrukh Jamal, Soha Othman, Gholamhossein G. Hamedani
Mathematical and Statistical Science Faculty Research and Publications
In this paper, we propose a new class of continuous distributions called the exponentiated generalized Topp Leone-G family that extends the Topp Leone-G family introduced by Al-Shomrani et al. (2016). We derive explicit expressions for certain mathematical properties of the new family such as; ordinary and incomplete moments, generating functions, reliability analysis, Lorenz and Bonferroni curves, Rényi entropy, stress strength model, moment of residual and reversed residual life, order statistics, extreme values and characterizations. We discuss the maximum likelihood estimates and the observed information matrix for the model parameters. Two real data sets are used to illustrate the flexibility of …
On The Exponentiated Weibull Rayleigh Distribution, Mohammed Elgarhy, Ibrahim Elbatal, Gholamhossein G. Hamedani, Amal Hassan
On The Exponentiated Weibull Rayleigh Distribution, Mohammed Elgarhy, Ibrahim Elbatal, Gholamhossein G. Hamedani, Amal Hassan
Mathematical and Statistical Science Faculty Research and Publications
A new four-parameter probability model, referred to the exponentiated Weibull Rayleigh (EWR) distribution, is introduced. Essential statistical properties of the distribution are considered. The maximum likelihood estimators of population parameters are given in case of complete sample. Simulation study is carried out to estimate the model parameters of EWR distribution. Additionally, parameter estimators are given in case of Type II censored samples. We come up with two applications to confirm the usefulness of the proposed distribution.
Novel Statistical Modeling Of Sleep Patterns In Drosophila Melanogaster, Luyang Wang
Novel Statistical Modeling Of Sleep Patterns In Drosophila Melanogaster, Luyang Wang
Doctoral Dissertations
”Sleep is one of the most important behaviors in animals, yet many aspects of sleep are not well understood. In humans, sleep has been shown to impact different aspects of health and cognitive performance. The fruit fly, Drosophila melanogaster, can be used as a model organism to investigate sleep patterns over an entire lifespan. The sleep-wake status can be recorded every minute over the life of individual flies, resulting in a wealth of data for identifying meaningful aspects of sleep. In this work, a framework based on statistical modeling methods is developed for sleep data collected on fruit flies …
How Ceo Wealth Affects The Riskiness Of A Firm, Sonik Mandal, Charlie Swartz, Sanjib Guha, Carl B. Mcgowan Jr.
How Ceo Wealth Affects The Riskiness Of A Firm, Sonik Mandal, Charlie Swartz, Sanjib Guha, Carl B. Mcgowan Jr.
Finance Faculty Publications
The objective of this paper is to analyze the relationship between the ownership level of managers and the risk averse behavior of the firm. We measure the ownership level of the managers by the ratio of their ownership of the company relative to their total wealth for a sample of 69 individuals from the Forbes 400 list of the wealthiest individuals in the world for the period from 2001-11 using an unbalanced panel data analysis. The dependent variable is the Altman Z-score of each firm and we further test these relationships using financial leverage. The independent variables are delta and …
A New Extension Of Lindley Distribution: Modified Validation Test, Characterizations And Different Methods Of Estimation, Mohamed Ibrahim, Abhimanyu Singh Yadav, Haitham M. Yousof, Hafida Goual, Gholamhossein Hamedani
A New Extension Of Lindley Distribution: Modified Validation Test, Characterizations And Different Methods Of Estimation, Mohamed Ibrahim, Abhimanyu Singh Yadav, Haitham M. Yousof, Hafida Goual, Gholamhossein Hamedani
Mathematical and Statistical Science Faculty Research and Publications
In this paper, a new extension of Lindley distribution has been introduced. Certain characterizations based on truncated moments, hazard and reverse hazard function, conditional expectation of the proposed distribution are presented. Besides, these characterizations, other statistical/mathematical properties of the proposed model are also discussed. The estimation of the parameters is performed through different classical methods of estimation. Bayes estimation is computed under gamma informative prior under the squared error loss function. The performances of all estimation methods are studied via Monte Carlo simulations in mean square error sense. The potential of the proposed model is analyzed through two data sets. …
The Zero Truncated Poisson Burr X Family Of Distributions With Properties, Characterizations, Applications, And Validation Test, T. H.M. Aboulemagd, Mohammed S. Hamed, Gholamhossein Hamedani, M. M. Ali, Hafida Goual, Mustafa Ç. Korkmaz, Haitham M. Yousof
The Zero Truncated Poisson Burr X Family Of Distributions With Properties, Characterizations, Applications, And Validation Test, T. H.M. Aboulemagd, Mohammed S. Hamed, Gholamhossein Hamedani, M. M. Ali, Hafida Goual, Mustafa Ç. Korkmaz, Haitham M. Yousof
Mathematical and Statistical Science Faculty Research and Publications
The goal of this work is to introduce a new family of continuous distributions with a strong physical application. Some statistical properties are derived, and certain useful characterizations of the proposed family distributions are presented. Five applications are provided to illustrate the importance of the new family. A modified goodness-of-fit test for the new family in complete data case are investigated via two examples. We propose, as a first step, the construction of Nikulin-Rao-Robson statistic based on chi-squared fit tests for the new family in the case of complete data. The new test is based on the Nikulin-Rao-Robson statistic separately …
Adding Value To Numerical Weather Predictions For The Aviation Industry In South Africa., Quinton Jacobs Mr., Willem A. Landman Prof.
Adding Value To Numerical Weather Predictions For The Aviation Industry In South Africa., Quinton Jacobs Mr., Willem A. Landman Prof.
International Journal of Aviation, Aeronautics, and Aerospace
The main objective of this study is to determine whether human forecasters at the main airports of South Africa add value to the raw numerical weather prediction model output when they provide forecast services to the aviation industry. Dataset pairs of weather observations made at these airports and terminal aerodrome forecasts are constructed for three forecast systems: the human forecasters, persistence forecast and the raw output from the 12 km resolution Unified Model administered by the South African Weather Service. These three dataset pairs are independently evaluated by a forecast verification system developed at the South African Weather Service. A …
การประยุกต์ใช้การเรียนรู้แบบเสริมกำลังกับการวางแผนทางการเงิน, ภัควัลย์ จันทรศิริภาส
การประยุกต์ใช้การเรียนรู้แบบเสริมกำลังกับการวางแผนทางการเงิน, ภัควัลย์ จันทรศิริภาส
Chulalongkorn University Theses and Dissertations (Chula ETD)
งานวิจัยนี้มีวัตถุประสงค์ที่จะนำการเรียนรู้แบบเสริมกำลังมาประยุกต์กับการวางแผนทางการเงินเพื่อตัดสินใจเลือกอัตราส่วนของสินทรัพย์ที่ใช้ในการบริโภคและการลงทุนในสินทรัพย์ที่มีความเสี่ยงที่ดีที่สุดในแต่ละช่วงเวลาตลอดช่วงอายุของครัวเรือน ผลลัพธ์ที่ได้จากการเรียนรู้แบบเสริมกำลังซึ่งเป็นค่าประมาณ จะถูกนำมาเปรียบเทียบกับคำตอบที่ถูกต้องจากวิธี MDP สำหรับการเรียนรู้แบบเสริมกำลังในงานวิจัยนี้เป็นอัลกอริธึม SARSA โดยการเลือกการกระทำใช้วิธี ε-greedy ส่วนการประมาณค่าใช้ตัวแบบถดถอยที่มีตัวแปรต้นเป็นฟีเจอร์จากเคอร์เนล Radial Basis Function (RBF) จากการศึกษาพบว่าความผิดพลาดระหว่างค่าประมาณผลลัพธ์ที่ดีที่สุดเทียบกับคำตอบจาก MDP มีแนวโน้มลู่เข้าสู่ศูนย์ แสดงว่าการเรียนรู้แบบเสริมกำลังสามารถประยุกต์กับการวางแผนทางการเงินได้ อย่างไรก็ตาม SARSA แบบดั้งเดิมใช้เวลานานในการเรียนรู้ เมื่อปรับปรุงให้การเลือกการกระทำในช่วงแรกเน้นสำรวจมากขึ้น พบว่า ความผิดพลาดลดลง แสดงให้เห็นว่า SARSA ที่ปรับปรุงให้เน้นการสำรวจในช่วงแรกมีประสิทธิภาพดีขึ้นกว่าแบบดั้งเดิม นอกจากนี้เมื่อพิจารณาผลของการปรับเปลี่ยนปัจจัยต่างๆ สำหรับ SARSA แบบเน้นการสำรวจในช่วงแรก พบว่า ความผิดพลาดระหว่างค่าประมาณผลลัพธ์ที่ดีที่สุดเทียบกับ MDP มีค่าน้อยสุดเมื่อใช้ค่าน้ำหนักเริ่มต้นจากตัวแบบการถดถอยเชิงเส้น, จำนวนฟีเจอร์ 200 ลักษณะ, อัตราการเรียนรู้และความน่าจะเป็นในการเลือกการกระทำแบบสำรวจแบบลดลงตามเวลาที่มีค่าเริ่มต้น 0.1 และ 0.9 ตามลำดับ ในขณะที่การนำคำตอบที่ดีที่สุดไปจำลองใช้จริง ผลของการวางแผนทางการเงินที่ได้มีความแตกต่างกับคำตอบจาก MDP มาก โดยการใช้ค่าน้ำหนักเริ่มต้นจากตัวแบบการถดถอยเชิงเส้น, จำนวนฟีเจอร์ 300 ลักษณะ, อัตราการเรียนรู้และความน่าจะเป็นในการเลือกการกระทำแบบสำรวจแบบลดลงตามเวลาที่มีค่าเริ่มต้น 0.1 และ 0.9 ตามลำดับให้ผลลัพธ์ที่ใกล้เคียงกับ MDP มากสุด แสดงว่าถึงแม้ความผิดพลาดของผลลัพธ์ที่ดีที่สุดจะมีค่าต่ำสุด คำตอบจากวิธีการเรียนรู้แบบเสริมกำลังยังมีความผิดพลาดสูงเมื่อเทียบกับคำตอบจาก MDP
ความอยู่ดีมีสุขของวัยรุ่น: การวิเคราะห์อภิมานโมเดลสมการเชิงโครงสร้าง, นัฏฐิกา เจริญตะคุ
ความอยู่ดีมีสุขของวัยรุ่น: การวิเคราะห์อภิมานโมเดลสมการเชิงโครงสร้าง, นัฏฐิกา เจริญตะคุ
Chulalongkorn University Theses and Dissertations (Chula ETD)
การวิจัยครั้งนี้มีจุดประสงค์เพื่อ 1) ศึกษาตัวแปรคุณลักษณะงานวิจัย 3 ด้านคือ ด้านการตีพิมพ์ ด้านเนื้อหาสาระ และด้านวิธีวิทยาการวิจัยที่ส่งผลต่อขนาดอิทธิพลของความฉลาดทางอารมณ์ การรู้คุณ การสนับสนุนทางสังคม รูปแบบการเผชิญปัญหา และการสนับสนุนความเป็นอิสระที่ส่งผลต่อความอยู่ดีมีสุขของวัยรุ่น 2) สร้างและตรวจสอบโมเดลความสัมพันธ์เชิงสาเหตุของปัจจัยความฉลาดทางอารมณ์ การรู้คุณ การสนับสนุนทางสังคม รูปแบบการเผชิญปัญหา และการสนับสนุนความเป็นอิสระที่ส่งผลต่อความอยู่ดีมีสุขของวัยรุ่น ตัวอย่างที่ใช้ในการศึกษาครั้งนี้เป็นงานวิจัยสหสัมพันธ์เชิงสาเหตุเกี่ยวกับ ความอยู่ดีมีสุขของวัยรุ่นที่เผยแพร่ในรูปแบบบทความวิจัยในช่วงปี ค.ศ. 2007-2019 จำนวน 67 เรื่องจากทั้งหมด 61,696 เรื่อง โดยใช้การวิเคราะห์อภิมานโมเดลสมการเชิงโครงสร้างด้วยโปรแกรม R และ Mplus ผลการวิจัยมีดังนี้ 1. คุณลักษณะงานวิจัย 3 ด้านส่งผลต่อขนาดอิทธิพลของความฉลาดทางอารมณ์ การรู้คุณ รูปแบบการเผชิญปัญหา การสนับสนุนทางสังคม และการสนับสนุนความเป็นอิสระที่มีต่อความอยู่ดีมีสุขของวัยรุ่นโดยมีขนาดอิทธิพลเท่ากับ .23-.58 .19-.56 .19-.31 .20-.55 และ .20-.47 ตามลำดับ โดยขนาดอิทธิพลของแต่ละตัวแปรอิสระที่มีต่อความอยู่ดีมีสุขจะได้รับอิทธิพลจากคุณลักษณะงานวิจัยทั้ง 3 ด้านแตกต่างกัน 2. โมเดลความสัมพันธ์เชิงสาเหตุความอยู่ดีมีสุขของวัยรุ่นที่พัฒนาขึ้น ประกอบด้วยปัจจัย 4 ด้านคือ ความฉลาดทางอารมณ์ การสนับสนุนทางสังคม รูปแบบการเผชิญปัญหา และการรู้คุณ ซึ่งอธิบาย ความผันแปรของความอยู่ดีมีสุขได้ร้อยละ 18.3 โดยโมเดลดังกล่าวสอดคล้องกับข้อมูลเชิงประจักษ์ (χ2= 2.518; df= 1; p-value = .113; CFI = 1.000; TLI = 1.000; RMSEA = .006) ทั้งนี้ความฉลาดทางอารมณ์มีอิทธิพลต่อความอยู่ดีมีสุขของวัยรุ่นมากที่สุด รองลงมาคือ การรู้คุณ รูปแบบการเผชิญปัญหา และการสนับสนุนทางสังคม (.249 .245 .116 และ .141 ตามลำดับ)
Site- And Location-Adjusted Approaches To Adaptive Allocation Clinical Trial Designs, Brian S. Di Pace
Site- And Location-Adjusted Approaches To Adaptive Allocation Clinical Trial Designs, Brian S. Di Pace
Theses and Dissertations
Response-Adaptive (RA) designs are used to adaptively allocate patients in clinical trials. These methods have been generalized to include Covariate-Adjusted Response-Adaptive (CARA) designs, which adjust treatment assignments for a set of covariates while maintaining features of the RA designs. Challenges may arise in multi-center trials if differential treatment responses and/or effects among sites exist. We propose Site-Adjusted Response-Adaptive (SARA) approaches to account for inter-center variability in treatment response and/or effectiveness, including either a fixed site effect or both random site and treatment-by-site interaction effects to calculate conditional probabilities. These success probabilities are used to update assignment probabilities for allocating patients …
Methods For Evaluating Dropout Attrition In Survey Data, Camille J. Hochheimer
Methods For Evaluating Dropout Attrition In Survey Data, Camille J. Hochheimer
Theses and Dissertations
As researchers increasingly use web-based surveys, the ease of dropping out in the online setting is a growing issue in ensuring data quality. One theory is that dropout or attrition occurs in phases that can be generalized to phases of high dropout and phases of stable use. In order to detect these phases, several methods are explored. First, existing methods and user-specified thresholds are applied to survey data where significant changes in the dropout rate between two questions is interpreted as the start or end of a high dropout phase. Next, survey dropout is considered as a time-to-event outcome and …
Assessing The Impact Of Incorporating Residential Histories Into The Spatial Analysis Of Cancer Risk, Anny-Claude Joseph
Assessing The Impact Of Incorporating Residential Histories Into The Spatial Analysis Of Cancer Risk, Anny-Claude Joseph
Theses and Dissertations
In many spatial epidemiologic studies, investigators use residential location at diagnosis as a surrogate for unknown environmental exposures or as a geographic basis for assigning measured exposures. Inherently, they make assumptions about the timing and location of pertinent exposures which may prove problematic when studying long latency diseases such as cancer.
In this work we explored how the association between environmental exposures and disease risk for long-latency health outcomes like cancer is affected by residential mobility. We used simulation studies conditioned on real data to evaluate the extent to which the commonly held assumption of no residential mobility 1) affected …
Methods For Joint Normalization And Comparison Of Hi-C Data, John C. Stansfield
Methods For Joint Normalization And Comparison Of Hi-C Data, John C. Stansfield
Theses and Dissertations
The development of chromatin conformation capture technology has opened new avenues of study into the 3D structure and function of the genome. Chromatin structure is known to influence gene regulation, and differences in structure are now emerging as a mechanism of regulation between, e.g., cell differentiation and disease vs. normal states. Hi-C sequencing technology now provides a way to study the 3D interactions of the chromatin over the whole genome. However, like all sequencing technologies, Hi-C suffers from several forms of bias stemming from both the technology and the DNA sequence itself. Several normalization methods have been developed for normalizing …
Latent Growth Model Approach To Characterize Maternal Prenatal Dna Methylation Trajectories, Dana Lapato
Latent Growth Model Approach To Characterize Maternal Prenatal Dna Methylation Trajectories, Dana Lapato
Theses and Dissertations
Background. DNA methylation (DNAm) is a removable chemical modification to the DNA sequence intimately associated with genomic stability, cellular identity, and gene expression. DNAm patterning reflects joint contributions from genetic, environmental, and behavioral factors. As such, differences in DNAm patterns may explain interindividual variability in risk liability for complex traits like major depression (MD). Hundreds of significant DNAm loci have been identified using cross-sectional association studies. This dissertation builds on that foundational work to explore novel statistical approaches for longitudinal DNAm analyses. Methods. Repeated measures of genome-wide DNAm and social and environmental determinants of health were collected up to six …
Genome-Wide Systems Genetics Of Alcohol Consumption And Dependence, Kristin Mignogna
Genome-Wide Systems Genetics Of Alcohol Consumption And Dependence, Kristin Mignogna
Theses and Dissertations
Widely effective treatment for alcohol use disorder is not yet available, because the exact biological mechanisms that underlie this disorder are not completely understood. One way to gain a better understanding of these mechanisms is to examine the genetic frameworks that contribute to the risk for developing this disorder. This dissertation examines genetic association data in combination with gene expression networks in the brain to identify functional groups of genes associated with alcohol consumption and dependence.
The first study took advantage of the behavioral complexity of human samples, and experimental capabilities provided by mouse models, by co-analyzing gene expression networks …
Spectral Methods For The Detection And Characterization Of Topologically Associated Domains, Kellen Garrison Cresswell
Spectral Methods For The Detection And Characterization Of Topologically Associated Domains, Kellen Garrison Cresswell
Theses and Dissertations
The three-dimensional (3D) structure of the genome plays a crucial role in gene expression regulation. Chromatin conformation capture technologies (Hi-C) have revealed that the genome is organized in a hierarchy of topologically associated domains (TADs), sub-TADs, and chromatin loops which is relatively stable across cell-lines and even across species. These TADs dynamically reorganize during development of disease, and exhibit cell- and conditionspecific differences. Identifying such hierarchical structures and how they change between conditions is a critical step in understanding genome regulation and disease development. Despite their importance, there are relatively few tools for identification of TADs and even fewer for …
Statistical Designs For Network A/B Testing, Victoria V. Pokhilko
Statistical Designs For Network A/B Testing, Victoria V. Pokhilko
Theses and Dissertations
A/B testing refers to the statistical procedure of experimental design and analysis to compare two treatments, A and B, applied to different testing subjects. It is widely used by technology companies such as Facebook, LinkedIn, and Netflix, to compare different algorithms, web-designs, and other online products and services. The subjects participating in these online A/B testing experiments are users who are connected in different scales of social networks. Two connected subjects are similar in terms of their social behaviors, education and financial background, and other demographic aspects. Hence, it is only natural to assume that their reactions to online products …
Design Of Experiment And Analysis Techniques For Fuel Consumption Data Using Heavy-Duty Diesel Vehicles And On-Road Testing, Sarah Ann Mills
Design Of Experiment And Analysis Techniques For Fuel Consumption Data Using Heavy-Duty Diesel Vehicles And On-Road Testing, Sarah Ann Mills
Graduate Theses, Dissertations, and Problem Reports (ETD)
Chassis dynamometer and on-road testing are usually employed to test vehicle operation. Testing on a chassis dynamometer reduces data variability compared to on-road testing due to the controlled environment but it does not account for other important variables that affects real-world vehicle operation. This study used on-road testing to investigate the differences between two test fuels under real-world conditions. Three heavy-duty diesel vehicles were driven on different routes for a period of three months. Each vehicle was instrumented with flow meters to gather fuel consumption data, which was then compared to the fuel rate broadcasted by the engine control unit …
Adult Atlantic Sturgeon Population Dynamics In The York River, Virginia, Jason E. Kahn
Adult Atlantic Sturgeon Population Dynamics In The York River, Virginia, Jason E. Kahn
Graduate Theses, Dissertations, and Problem Reports (ETD)
Sturgeon first appear in the fossil record in the Triassic Period just over 200 million years ago and are among the most primitive of the bony fishes. Despite their large size and historic presence along the East Coast, Atlantic sturgeon were not targeted for their meat and caviar as a commercial fishery until 1880. By 1905 they had declined to less than one percent of their pre-fishing abundance but the fishery continued. Prior to 1980, there had been very little research on Atlantic sturgeon, primarily limited to documenting landing location and poundage, maximum longevity, or weight of eggs per fish. …
Reliability Analysis For Systems With Outsourced Components, Zhengwei Hu
Reliability Analysis For Systems With Outsourced Components, Zhengwei Hu
Doctoral Dissertations
"The current business model for many industrial firms is to function as system integrators, depending on numerous outsourced components from outside component suppliers. This practice has resulted in tremendous cost savings; it makes system reliability analysis, however, more challenging due to the limited component information available to system designers. The component information is often proprietary to component suppliers. Motivated by the need of system reliability prediction with outsourced components, this work aims to explore feasible ways to accurately predict the system reliability during the system design stage. Four methods are proposed. The first method reconstructs component reliability functions using limited …
Statistical Modeling Of Influenza-Like-Illness In Montana Using Spatial And Temporal Methods, Benjamin A. Stark
Statistical Modeling Of Influenza-Like-Illness In Montana Using Spatial And Temporal Methods, Benjamin A. Stark
Graduate Student Theses, Dissertations, & Professional Papers
Studying air pollution and public health has been a historically important question in science. It has long been hypothesized that severe air pollution conditions lead to negative implications in basic human health. Primarily, areas thats are prone to severe degrees of human pollution are the focus of such studies. Such research relating to less populated areas are scarce, and this scarcity raises the question of how such pollution dynamics (human-made and natural) influence human health in more rural areas.
The aim of this study is to explore this hole in research; in particular we explore possible links between air pollution …