Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Theses/Dissertations

Statistics and Probability

2010

Institution
Keyword
Publication

Articles 1 - 30 of 108

Full-Text Articles in Physical Sciences and Mathematics

Dna Methylation And Its Association With Prenatal Exposures And Pregnancy Outcomes, Jennifer Straughen Dec 2010

Dna Methylation And Its Association With Prenatal Exposures And Pregnancy Outcomes, Jennifer Straughen

USF Tampa Graduate Theses and Dissertations

Altered DNA methylation may lead to suboptimal fetal programming, increasing the risk of adverse pregnancy outcomes such as small for gestational age (SGA); however, few studies have examined the associations between DNA methylation, prenatal exposures, and fetal outcomes. Cross-sectional data from a larger, ongoing study were used to assess the impact of prenatal smoking on gene specific methylation of umbilical cord blood derived DNA and to investigate the association between gene-specific methylation and risk of SGA. The association between gene-specific DNA methylation and birthweight was also assessed. Maternal and infant covariates were abstracted from medical records, cigarette smoke exposure was …


Evaluation Of Common Inherited Variants In Mitochondrial-Related And Microrna-Related Genes As Novel Risk Factors For Ovarian Cancer, Jennifer Permuth Wey Dec 2010

Evaluation Of Common Inherited Variants In Mitochondrial-Related And Microrna-Related Genes As Novel Risk Factors For Ovarian Cancer, Jennifer Permuth Wey

USF Tampa Graduate Theses and Dissertations

Epithelial ovarian cancer (EOC) is a leading cause of morbidity and mortality among women in the United States, and the etiology is incompletely understood. Common, low penetrant genetic variants such as single nucleotide polymorphisms (SNPs) likely contribute to a significant proportion of EOC. We examined whether SNPs in two understudied yet biologically important types of genes, mitochondrial-related and miRNA-related genes, may contribute to EOC susceptibility using data from a large, homogeneous study population of 1,815 EOC cases and 1,900 controls (frequency-matched on age-group and race/ethnicity) genotyped through stage 1 of an ongoing genome-wide association study. Inter-individual variation in genes involved …


Like Mother Like Child: An Investigation Of Mother Characteristics And Child Temperaments, Tempus Fugitt Dec 2010

Like Mother Like Child: An Investigation Of Mother Characteristics And Child Temperaments, Tempus Fugitt

Statistics

Much research has gone into what biological and social factors raise the risk of children developing cognitive, social, or behavioral problems. This project looks at what characteristics of the mother are significantly associated with different temperaments in the child which may predict problems developed in the child later in life. These characteristics include mother’s age, her education level, household income, parenting attitudes, involvement with the child, and drug and alcohol use. Data was used from the Fragile Families and Child Wellbeing Study conducted by the Office of Population Research at Princeton University. Cumulative logistic regression was used to analyze the …


Poisson Process Monitoring, Test And Comparison, Qing Chen Dec 2010

Poisson Process Monitoring, Test And Comparison, Qing Chen

UNLV Theses, Dissertations, Professional Papers, and Capstones

The task of determining whether a sudden change occurred in the generative parameters of a time series generates application in many areas. In this thesis, we aim at monitoring the change-point of a Poisson process by method, which is characterized by a forward-backward testing algorithm and several overall error control mechanisms. With the application of this proposed method, we declare that Mount Etna is not a simple Poissonian volcano, because two different regimes divided by the change point, January 30th 1974, are identified. The validation procedures, used in a complementary fashion, by the formal hypothesis tests and graphical method will …


Bayesian Logistic Regression Model For Siting Biomass-Using Facilities, Xia Huang Dec 2010

Bayesian Logistic Regression Model For Siting Biomass-Using Facilities, Xia Huang

Masters Theses

Key sources of oil for western markets are located in complex geopolitical environments that increase economic and social risk. The amalgamation of economic, environmental, social and national security concerns for petroleum-based economies have created a renewed emphasis on alternative sources of energy which include biomass. The stability of sustainable biomass markets hinges on improved methods to predict and visualize business risk and cost to the supply chain.

This thesis develops Bayesian logistic regression models, with comparisons of classical maximum likelihood models, to quantify significant factors that influence the siting of biomass-using facilities and predict potential locations in the 13-state Southeastern …


Coronary Heart Disease Mortality And Long-Term Exposure To Ambient Particulate Air Pollutants In Elderly Nonsmoking California Residents, Lie Hong Chen Dec 2010

Coronary Heart Disease Mortality And Long-Term Exposure To Ambient Particulate Air Pollutants In Elderly Nonsmoking California Residents, Lie Hong Chen

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study is to assess the effect of long-term concentrations of ambient PM on risks of all causes, cardiopulmonary, coronary heart disease (CHD), total cancer, and any mention of nonmalignant respiratory disease (NMRD) mortality.

The health effects of long-term ambient air pollution have been studied with up to 30 years of follow-up in the AHSMOG cohort, a cohort of 6,338 nonsmoking white California adults. Monthly concentrations of ambient air pollutants [particulate matter(PMio), Ozone (O3), sulfur dioxide (SO2), nitrogen dioxide (NO2) or particulate matter

In the AHSMOG cohort, each increment of 10 |ig/m3 in PMio in two-pollutant models …


An Investigation Of Process Parameters To Optimize The Fiber Diameter Of Electrospun Vascular Scaffolds Through Experimental Design, Steffi Wong Dec 2010

An Investigation Of Process Parameters To Optimize The Fiber Diameter Of Electrospun Vascular Scaffolds Through Experimental Design, Steffi Wong

Biomedical Engineering

No abstract provided.


Robust Interval Estimation Of A Treatment Effect In Observational Studies Using Propensity Score Matching, Scott F. Kosten Dec 2010

Robust Interval Estimation Of A Treatment Effect In Observational Studies Using Propensity Score Matching, Scott F. Kosten

Dissertations

Estimating the treatment effect between a treatment group and a control group in an observational study is a challenging problem in statistics. Without random assignment of subjects, there are likely to be differences between the treatment group and control group on a set of baseline covariates. If one of these baseline covariates is correlated to the response variable, then the difference in sample means between the groups is likely to be a biased estimate of the true treatment effect.

Propensity score matching has become an increasingly popular strategy for reducing bias in estimates of the treatment effect. This reduction in …


Confidence Intervals And Tests On The Difference Of Means Of Two Delta Distributions, Karen Grace Villarente Rosales Dec 2010

Confidence Intervals And Tests On The Difference Of Means Of Two Delta Distributions, Karen Grace Villarente Rosales

Dissertations

Various research fields produce data that are lognormally distributed and inflated with zero values. This type of data follows a delta distribution. In this study, we want to extensively investigate different interval and hypothesis testing methods for comparing the means of two delta populations to see which methods are optimal under different conditions of the populations.

For confidence intervals, existing MVUE methods are extended to two sample cases and compared to classical and two proposed robust methods. We investigated the performance of the classical Student's t, Welch t, and Wilcoxon-based interval to see if these methods really perform badly on …


Psychometric Properties Of Postsecondary Students' Course Evaluations, Michael J. Drysdale Dec 2010

Psychometric Properties Of Postsecondary Students' Course Evaluations, Michael J. Drysdale

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Several experts in the area of postsecondary student evaluations of courses have concluded that they are stable or reliable measures as well as being measures that provide ways of making valid inferences regarding teacher effectiveness. Often these experts have offered these conclusions without supporting evidence. Surprisingly, a thorough review of the literature revealed very few reported test-retest reliability studies of course evaluations and the results from these studies are contradictory. In the area of validity, the conclusions offered by scholars who conducted meta-analyses of mutlisection course studies are inconsistent. This leads to the following two research questions:

1. What is …


Spatial Epidemiology Of Birth Defects In The United States And The State Of Utah Using Geographic Information Systems And Spatial Statistics, Samson Y. Gebreab Dec 2010

Spatial Epidemiology Of Birth Defects In The United States And The State Of Utah Using Geographic Information Systems And Spatial Statistics, Samson Y. Gebreab

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Oral clefts are the most common form of birth defects in the United States (US) and the State of Utah has among the highest prevalence of oral clefts in the nation. The overall objective of this dissertation was to examine the spatial distribution of oral clefts and their linkage with a broad range of demographic, behavioral, social, economic, and environmental risk factors through the application of Geographic Information Systems (GIS) and spatial statistics. Using innovative linked micromaps plots, we investigated the geographic patterns of oral clefts occurrence from 1998 to 2002 and their relationships with maternal smoking rates and proportion …


The Determinants Of Colorectal Cancer Survival Disparities In Nevada, Lucas N. Wassira Dec 2010

The Determinants Of Colorectal Cancer Survival Disparities In Nevada, Lucas N. Wassira

UNLV Theses, Dissertations, Professional Papers, and Capstones

Different population groups across Nevada and throughout the United States suffer disproportionately from colorectal cancer and its after-effects. Overcoming cancer health disparities is important for lessening the burden of cancer. There has been an overall decline in the incidence of and mortality from colorectal cancer (CRC). This is likely due, in part, to the increasing use of screening procedures such as Fecal Occult Blood Test (FOBT) and/or endoscopy, which can reduce the risk of CRC mortality by fifty percent. Nevertheless, screening procedures are routinely used by only fifty percent of Americans aged fifty years and older. Despite overall mortality decreasing …


Effects Of Acculturation On Hiv/Aids Sexual Risk Behaviors Among Asian And Pacific Islander (Api) Women, Margaret Cabotage Salud Dec 2010

Effects Of Acculturation On Hiv/Aids Sexual Risk Behaviors Among Asian And Pacific Islander (Api) Women, Margaret Cabotage Salud

Loma Linda University Electronic Theses, Dissertations & Projects

Background. In the US women are the fastest growing group for sexually transmitted infections (STIs), including HIV and AIDS. In addition, the estimated AIDS cases among female adults and adolescents, aged 13-19, increased from 7% in 1985 to approximately 26% in 2002. Most infections occur by heterosexual transmission with 53% occurring through contact with a high-risk sexual partner. While overall HIV/AIDS rates in the Asian Pacific Islander (API) community remain low, they are rising and HIV testing rates, one of the major prevention strategies for HIV, are lower than that of other populations. Furthermore, very little is known about APIs …


Cost-Efficient Variable Selection Using Branching Lars, Li Hua Yue Nov 2010

Cost-Efficient Variable Selection Using Branching Lars, Li Hua Yue

Electronic Thesis and Dissertation Repository

Variable selection is a difficult problem in statistical model building. Identification of cost efficient diagnostic factors is very important to health researchers, but most variable selection methods do not take into account the cost of collecting data for the predictors. The trade off between statistical significance and cost of collecting data for the statistical model is our focus. A Branching LARS (BLARS) procedure has been developed that can select and estimate the important predictors to build a model not only good at prediction but also cost efficient. BLARS method is an extension of the LARS variable selection method to incorporate …


Inferential Methods For High-Throughput Methylation Data, Maria Capparuccini Nov 2010

Inferential Methods For High-Throughput Methylation Data, Maria Capparuccini

Theses and Dissertations

The role of abnormal DNA methylation in the progression of disease is a growing area of research that relies upon the establishment of sound statistical methods. The common method for declaring there is differential methylation between two groups at a given CpG site, as summarized by the difference between proportions methylated db=b1-b2, has been through use of a Filtered Two Sample t-test, using the recommended filter of 0.17 (Bibikova et al., 2006b). In this dissertation, we performed a re-analysis of the data used in recommending the threshold by fitting a mixed-effects ANOVA model. It was determined that the 0.17 filter …


Survival Analysis Of Microarray Data With Microarray Measurement Subject To Measurement Error, Juan Xiong Nov 2010

Survival Analysis Of Microarray Data With Microarray Measurement Subject To Measurement Error, Juan Xiong

Electronic Thesis and Dissertation Repository

Microarray technology is essentially a measurement tool for measuring expressions of genes, and this measurement is subject to measurement error. Gene expressions could be employed as predictors for patient survival, and the measurement error involved in the gene expression is often ignored in the analysis of microarray data in the literature. Efforts are needed to establish statistical method for analyzing microarray data without ignoring the error in gene expression. A typical microarray data set has a large number of genes far exceeding the sample size. Proper selection of survival relevant genes contributes to an accurate prediction model. We study the …


Power And Sample Size For Three-Level Cluster Designs, Tina Cunningham Nov 2010

Power And Sample Size For Three-Level Cluster Designs, Tina Cunningham

Theses and Dissertations

Over the past few decades, Cluster Randomized Trials (CRT) have become a design of choice in many research areas. One of the most critical issues in planning a CRT is to ensure that the study design is sensitive enough to capture the intervention effect. The assessment of power and sample size in such studies is often faced with many challenges due to several methodological difficulties. While studies on power and sample size for cluster designs with one and two levels are abundant, the evaluation of required sample size for three-level designs has been generally overlooked. First, the nesting effect introduces …


Exploring Evaluation In School Districts: School District Evaluators And Their Practice, Susan Hibbard Nov 2010

Exploring Evaluation In School Districts: School District Evaluators And Their Practice, Susan Hibbard

USF Tampa Graduate Theses and Dissertations

This study explored the evaluation practices of internal evaluators in public school districts in a large southern state. The individuals who conduct evaluations in school districts as internal evaluators were identified and background information was collected. The education and training in evaluation was investigated and the types of evaluations typically conducted by those individuals. Respondents (n = 134) revealed conducting evaluations was a secondary role and part of their main job responsibilities. The types of evaluations carried out and the way in which evaluation was practices were revealed. A descriptive framework of the individuals who conduct evaluations in school districts …


Model Selection With Information Criteria, Changjiang Xu Oct 2010

Model Selection With Information Criteria, Changjiang Xu

Electronic Thesis and Dissertation Repository

This thesis is on model selection using information criteria. The information criteria include generalized information criterion and a family of Bayesian information criteria. The properties and improvement of the information criteria are investigated.

We analyze nonasymptotic and asymptotic properties of the information criteria for linear models, probabilistic models, and high dimensional models, respectively. We give probability of selecting a model and compute the probability by Monte Carlo methods. We derive the conditions under which the criteria are consistent, underfitting, or overfitting.

We further propose new model selection procedures to improve the information criteria. The procedures combine the information criteria with …


Stereotype Logit Models For High Dimensional Data, Andre Williams Oct 2010

Stereotype Logit Models For High Dimensional Data, Andre Williams

Theses and Dissertations

Gene expression studies are of growing importance in the field of medicine. In fact, subtypes within the same disease have been shown to have differing gene expression profiles (Golub et al., 1999). Often, researchers are interested in differentiating a disease by a categorical classification indicative of disease progression. For example, it may be of interest to identify genes that are associated with progression and to accurately predict the state of progression using gene expression data. One challenge when modeling microarray gene expression data is that there are more genes (variables) than there are observations. In addition, the genes usually demonstrate …


Assessment Of Acgh Clustering Methodologies, Serena F. Baker Oct 2010

Assessment Of Acgh Clustering Methodologies, Serena F. Baker

Theses and Dissertations

Array comparative genomic hybridization (aCGH) is a technique for identifying duplications and deletions of DNA at specific locations across a genome. Potential objectives of aCGH analysis are the identification of (1) altered regions for a given subject, (2) altered regions across a set of individuals, and (3) clinically relevant clusters of hybridizations. aCGH analysis can be particularly useful when it identifies previously unknown clusters with clinical relevance. This project focuses on the assessment of existing aCGH clustering methodologies. Three methodologies are considered: hierarchical clustering, weighted clustering of called aCGH data, and clustering based on probabilistic recurrent regions of alteration within …


Statistical Image Recovery From Laser Speckle Patterns With Polarization Diversity, Donald B. Dixon Sep 2010

Statistical Image Recovery From Laser Speckle Patterns With Polarization Diversity, Donald B. Dixon

Theses and Dissertations

This research extends the theory and understanding of the laser speckle imaging technique. This non-traditional imaging technique may be employed to improve space situational awareness and image deep space objects from a ground-based sensor system. The use of this technique is motivated by the ability to overcome aperture size limitations and the distortion effects from Earth’s atmosphere. Laser speckle imaging is a lensless, coherent method for forming two-dimensional images from their autocorrelation functions. Phase retrieval from autocorrelation data is an ill-posed problem where multiple solutions exist. This research introduces polarization diversity as a method for obtaining additional information so the …


Application Of Convex Methods To Identification Of Fuzzy Subpopulations, Ryan Lee Eliason Sep 2010

Application Of Convex Methods To Identification Of Fuzzy Subpopulations, Ryan Lee Eliason

Theses and Dissertations

In large observational studies, data are often highly multivariate with many discrete and continuous variables measured on each observational unit. One often derives subpopulations to facilitate analysis. Traditional approaches suggest modeling such subpopulations with a compilation of interaction effects. However, when many interaction effects define each subpopulation, it becomes easier to model membership in a subpopulation rather than numerous interactions. In many cases, subjects are not complete members of a subpopulation but rather partial members of multiple subpopulations. Grade of Membership scores preserve the integrity of this partial membership. By generalizing an analytic chemistry concept related to chromatography-mass spectrometry, we …


Geometry Of Satake And Toroidal Compactifications, Patrick Michael Boland Sep 2010

Geometry Of Satake And Toroidal Compactifications, Patrick Michael Boland

Open Access Dissertations

In [JM02, section 14], Ji and MacPherson give new constructions of the Borel--Serre and reductive Borel--Serre compactifications [BS73, Zuc82] of a locally symmetric space. They use equivalence classes of eventually distance minimizing (EDM) rays to describe the boundaries of these compactications. The primary goal of this thesis is to construct the Satake compactifications of a locally symmetric space [Sat60a] using finer equivalence relations on EDM rays. To do this, we first construct the Satake compactifications of the global symmetric space [Sat60b] with equivalence classes of geodesics in the symmetric space. We then define equivalence relations on EDM rays using geometric …


A Hierarchical Spherical Radial Quadrature Algorithm For Multilevel Glmms, Gsmms, And Gene Pathway Analysis, Jacob A. Gagnon Sep 2010

A Hierarchical Spherical Radial Quadrature Algorithm For Multilevel Glmms, Gsmms, And Gene Pathway Analysis, Jacob A. Gagnon

Open Access Dissertations

The first part of my thesis is concerned with estimation for longitudinal data using generalized semi-parametric mixed models and multilevel generalized linear mixed models for a binary response. Likelihood based inferences are hindered by the lack of a closed form representation. Consequently, various integration approaches have been proposed. We propose a spherical radial integration based approach that takes advantage of the hierarchical structure of the data, which we call the 2 SR method. Compared to Pinheiro and Chao's multilevel Adaptive Gaussian quadrature, our proposed method has an improved time complexity with the number of functional evaluations scaling linearly in the …


Psychological Profiles In A Female Bariatric Surgery Sample, Aimee L. Donato Sep 2010

Psychological Profiles In A Female Bariatric Surgery Sample, Aimee L. Donato

Loma Linda University Electronic Theses, Dissertations & Projects

Morbid obesity is an epidemic. Current literature suggests that people with morbid obesity tend to show increased levels of psychological dysfunction. This is especially pertinent to the clinicians who work with morbidly obese patients who seek bariatric surgery as the method for weight control. Surgery should be performed on patients who are psychologically ready to adjust to the stringent post-operative lifestyle.

The purpose of the present study was (1) to compare two groups of bariatric patients (a White group and a non-White group) on pre-surgery measures: specific scales on the Millon Behavioral Medicine Diagnostic (MBMD), the Beck Depression Inventory II …


Veterans Of The 1st Persian Gulf War: A Study Of Medically Unexplained Symptom Models, Alexis H. Collins Sep 2010

Veterans Of The 1st Persian Gulf War: A Study Of Medically Unexplained Symptom Models, Alexis H. Collins

Loma Linda University Electronic Theses, Dissertations & Projects

In 1990-1991, shortly after the Persian Gulf War, a number of veterans began complaining about a wide range of symptoms, the most common of which were; fatigue, headache, sleep disturbance, low mood, and memory loss. These symptoms were similar to those experienced by individuals with Medically Unexplained Illnesses such as Chronic Fatigue Syndrome, Fibromyalgia, Irritable Bowel Syndrome, Multiple Chemical Sensitivity, and Somatoform Disorders. Utilizing structural equation modeling and data gathered from the Gulf War Veterans Health Questionnaire, this study attempted to determine whether symptoms experienced by veterans were best explained as individual items, discrete illnesses, or as a conglomeration of …


Comparison Of Non-Surgical And Surgical Endodontic Retreatment: A Systematic Review, Robert Corr Sep 2010

Comparison Of Non-Surgical And Surgical Endodontic Retreatment: A Systematic Review, Robert Corr

Loma Linda University Electronic Theses, Dissertations & Projects

Primary root canal therapy has been shown to be a predictable procedure with a high degree of success 1-4, however failures can occur after treatment. Treatment options for the preservation of teeth that have had previous endodontic treatment but demonstrate persistent disease include non-surgical (orthograde) or surgical (retrograde) endodontic retreatment, assuming the tooth is restorable, periodontally sound, and the patient desires to retain the tooth. The purpose of this study was to conduct a systematic review of the current available evidence to compare the clinical and radiographic outcomes of nonsurgical with those of surgical endodontic retreatment. Methodology began with …


Facial Type Analysis Comparison Between Mri, Cbct, And Lateral Cephalometrics, Matthew A. Sanders Sep 2010

Facial Type Analysis Comparison Between Mri, Cbct, And Lateral Cephalometrics, Matthew A. Sanders

Loma Linda University Electronic Theses, Dissertations & Projects

Introduction: Single Cephalometric measurements are comparable between Cone Beam Computed Tomography (CBCT), Magnetic Resonance Imaging (MRl) and Conventional Lateral Cephalometric (LC) imaging methods. This study evaluated the agreement between the three imaging methods in facial type analysis (using a composite of 5 cephalometric measures).

Methods and Materials: Twenty-two subjects participated in this study. Cranial images were generated via three modalities: LC, CBCT and MRl. Cephalometric landmarks were identified on the three images per subject and a facial type analysis performed. An equally weighted facial type calculation composed of 5 cephalometric measurements (facial axis, facial depth, mandibular plane, lower face height, …


The Use Of The Minnesota Multiphasic Personality Inventory-Ii (Mmpi-2) In Pre-Employment Evaluations, Ana M. Gamez Sep 2010

The Use Of The Minnesota Multiphasic Personality Inventory-Ii (Mmpi-2) In Pre-Employment Evaluations, Ana M. Gamez

Loma Linda University Electronic Theses, Dissertations & Projects

Psychological testing is an important facet in the selection and hiring processes of law enforcement and public safety personnel. Research in this area suggests that the MMPI-2 scales have been correlated with problematic behavior among police officers, poor job performance, and officer misconduct. This study examined the extent to which suitability for hire could be predicted by the MMPI-2 scale L (Lie), scale K (correction), Infrequency scale (F), scale 4 Psychopathic Deviate (Pd), scale 6 Paranoia (Pa), scale 7 Psychasthenia (Pt), and scale 9 Hypomania (Ma). It examined whether profile differences emerged as a function of suitability across gender, between …