Statistics and Probability Commons^™

Underlying Distributions In Loglinear Models Of Discrete Data, Tim Moses

Journal of Modern Applied Statistical Methods

The implications of loglinear models based on underlying uniform and binomial distribution are assessed with respect to modeling eight distributions. Regarding statistical selection of the loglinear models’ parameterizations, results indicate that better fitting models are obtained when the distribution being modeled is dissimilar to the underlying distribution used. For loglinear models with predetermined numbers of parameters, results suggest that better fitting models can be obtained when the distribution being modeled is similar to the underlying distribution.

Robust Modifications Of The Levene And O’Brien Tests For Spread, Abdul R. Othman, The Sin Yan, H. J. Keselman, Rand R. Wilcox, James Algina

Journal of Modern Applied Statistical Methods

Variants of Levene’s and O’Brien’s procedures not investigated by Keselman, Wilcox & Algina (2008) were examined. Simulations indicate that a new O’Brien variant provides very good Type I error control and is simpler for applied researchers to compute than the method recommended by Keselman, et al.

An Extension Of The Seasonal Kpss Test, Sami Khedhiri, Ghassen El Montasser

Journal of Modern Applied Statistical Methods

The limit theory of the seasonal KPSS test is established under the null hypothesis using seasonal dummy variables. Taking these variables into account can result in improved finite sample performance of the test. The seasonal KPSS test can be interpreted as a test of deterministic seasonality and it may be used in addition to seasonal unit root tests to analyze the dynamic properties of time series. The seasonal indicator variables provide the test with an explicit model-based regression that in itself constitutes a support for its limit theory.

Improved Estimator In The Presence Of Multicollinearity, Ghadban Khalaf

Journal of Modern Applied Statistical Methods

The performances of two biased estimators for the general linear regression model under conditions of collinearity are examined and a new proposed ridge parameter is introduced. Using Mean Square Error (MSE) and Monte Carlo simulation, the resulting estimator’s performance is evaluated and compared with the Ordinary Least Square (OLS) estimator and the Hoerl and Kennard (1970a) estimator. Results of the simulation study indicate that, with respect to MSE criteria, in all cases investigated the proposed estimator outperforms both the OLS and the Hoerl and Kennard estimators.

The Weighted Hellinger Distance For Kernel Distribution Estimator Of Function Of Observations, Abdel-Razzaq Mugdadi

Journal of Modern Applied Statistical Methods

The asymptotic mean weighted Hellinger distance (AMWHD) is derived for the kernel distribution estimator of a function of observations. In addition, the AMWHD is compared with the asymptotic mean integrated square error (AMISE) of the estimator. A completely data based method is proposed to select the bandwidth in the estimator using the mean weighted Hellinger distance (MWHD).

Retention Of Statistical Concepts In A Preliminary Randomization-Based Introductory Statistics Curriculum, Nathan L. Tintle, Kylie Topliff, Jill Vanderstoep, Vicki-Lynn Holmes, Todd Swanson

Faculty Work Comprehensive List

Previous research suggests that a randomization-based introductory statistics course may improve student learning compared to the consensus curriculum. However, it is unclear whether these gains are retained by students post-course. We compared the conceptual understanding of a cohort of students who took a randomization-based curriculum (n = 76) to a cohort of students who used the consensus curriculum (n = 79). Overall, students taking the randomization-based curriculum showed higher conceptual retention in areas emphasized in the curriculum, with no significant decrease in conceptual retention in other areas. This study provides additional support for the use of randomization-methods in teaching introductory …

The Efficacy Of An Audio Program And Discussion Guide In Promoting Exclusive Breastfeeding In Cameroon, Africa, Kathryn R. Reinsma

Loma Linda University Electronic Theses, Dissertations & Projects

Background: In the Northwest Region of Cameroon, approximately 90% of women initiate breastfeeding; however, only 34% continue exclusive breastfeeding for the recommended six months (Kakute, et al., 2005; WHO, 2008). Entertainment-education is a mass-media communication strategy of placing educational information into media such as television programs, movies, and radio programs (Siegel & Lotenberg, 2007). This form of behavioral change communication has proven effective in addressing health-related issues in developing countries.

Purpose: The aim was to design an audio program and discussion guide to test the hypothesis that an audio program and discussion guide improves exclusive breastfeeding knowledge, beliefs, benefits, self-efficacy, …

Human Gene Copy Number Spectra Analysis In Congenital Heart Malformations, Aoy Tomita-Mitchell, Donna K. Mahnke, Craig Struble, Maureen E. Tuffnell, Karl D. Stamm, Mats Hidestrand, Susan Harris, Mary A. Goetsch, Pippa Simpson, David P. Bick, Ulrich Broeckel, Andrew N. Pelech, James S. Tweddell, Michael Mitchell

Mathematics, Statistics and Computer Science Faculty Research and Publications

The clinical significance of copy number variants (CNVs) in congenital heart disease (CHD) continues to be a challenge. Although CNVs including genes can confer disease risk, relationships between gene dosage and phenotype are still being defined. Our goal was to perform a quantitative analysis of CNVs involving 100 well-defined CHD risk genes identified through previously published human association studies in subjects with anatomically defined cardiac malformations. A novel analytical approach permitting CNV gene frequency “spectra” to be computed over prespecified regions to determine phenotype-gene dosage relationships was employed. CNVs in subjects with CHD (n = 945), subphenotyped into 40 …

Genomic Analysis Of Immune Response Against Vibrio Cholerae Hemolysin In Caenorhabditis Elegans, Surasri N. Sahu, Jada Lewis, Isha Patel, Serdar Bozdag, Jeong H. Lee, Joseph E. Leclerc, Hediye Nese Cinar

Mathematics, Statistics and Computer Science Faculty Research and Publications

Vibrio cholerae cytolysin (VCC) is among the accessory V. cholerae virulence factors that may contribute to disease pathogenesis in humans. VCC, encoded by hlyA gene, belongs to the most common class of bacterial toxins, known as poreforming toxins (PFTs). V. cholerae infects and kills Caenorhabditis elegans via cholerae toxin independent manner. VCC is required for the lethality, growth retardation and intestinal cell vacuolation during the infection. However, little is known about the host gene expression responses against VCC. To address this question we performed a microarray study in C. elegans exposed to V. cholerae strains with intact and deleted hlyA …

H-Colouring Bipartite Graphs, John Engbers, David Galvin

Mathematics, Statistics and Computer Science Faculty Research and Publications

For graphs G and H, an H-colouring of G (or homomorphism from G to H) is a function from the vertices of G to the vertices of H that preserves adjacency. H-colourings generalize such graph theory notions as proper colourings and independent sets. For a given H, k∈V(H) and G we consider the proportion of vertices of G that get mapped to k in a uniformly chosen H-colouring of G. Our main result concerns this quantity when G is regular and bipartite. We find numbers 0⩽a−(k)⩽a+(k)⩽1 with the property that for all such G, with high probability the proportion is …

Analyzing Financial Data Through Interactive Visualization, Fizi Yadav

Purdue Polytechnic Masters Theses

This investigation explored the role data visualization in the scientific community and its effect on the cognitive ability of an individual. The research attempted to answer the question, “ Whether appropriate data visualization helps in better understanding of corporate financial data?” and used quantitative methods to gain an insight. Participants in the study were divided into two groups of 30 each, with one group receiving the treatment devised for the research and the other using the common prevalent method. Both the groups were subjected to a test, based upon the analysis of which a conclusion was derived. The subjects were …

Assessing Changes In The Abundance Of The Continental Population Of Scaup Using A Hierarchical Spatio-Temporal Model, Beth E. Ross

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

In ecological studies, the goal is often to describe and gain further insight into ecological processes underlying the data collected during observational studies. Because of the nature of observational data, it can often be difficult to separate the variation in the data from the underlying process or 'state dynamics.' In order to better address this issue, it is becoming increasingly common for researchers to use hierarchical models. Hierarchical spatial, temporal, and spatio-temporal models allow for the simultaneous modeling of both first and second order processes, thus accounting for underlying autocorrelation in the system while still providing insight into overall spatial …

Interactive Random Forests Plots, Anna T. Quach

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Random Forests is a useful data mining tool that is quite popular in finding variable importance. However, many people don’t make use of the Random Forests results in interactive graphs. Partly, this is because software packages that can do interactive graphs can’t handle large data sets and those that use Random Forests have large data sets or many variables. A new software package in R, known as iPlots eXtreme, that is still in development makes it simple to explore large data sets interactively. I have created a function, called irfplot (interactive random forests plot) that specifically uses Random Forests to …

Simulating Loan Repayment By The Sinking Fund Method (Sinking Fund Governed By A Sequence Of Interest Rates), Placede Judicaelle Gangnang Fosso

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The sinking fund method is a way to repay a loan where the borrower pays the amount of interest accrued by the principal at the end of each time period and puts a certain amount in a sinking fund in order to repay the principal at the end of the loan. Usually, we assume that the interest rate on the sinking fund is the same during the entire time of the loan. In the study, we will depart from the usual assumptions and will look at different scenarios, including when changes of the interest rate on the sinking fund follows …

Ignoring The Spatial Context In Intro Statistics Classes - And Some Simple Graphical Remedies, Nathan Voge

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Statistical data often have a spatial (geographic) context, be it countries of the world, states in the US, counties within a state, cities across the globe, or locations where measurements have been taken. However, most introductory statistics books do not even suggest that such data often are not independent from location, but rather are eected by some spatial association. Remedies are simple: Display data via various map views and brie y discuss which additional information can be extracted from such a graphical representation. In this report, we will visit a variety of popular introductory statistics textbooks and show how some …

Using The R Library Rpanel For Gui-Based Simulations In Introductory Statistics Courses, Ryan M. Allison

Statistics

As a student, I noticed that the statistical package R (http://www.r-project.org) would have several benefits of its usage in the classroom. One benefit to the package is its free and open-source nature. This would be a great benefit for instructors and students alike since it would be of no cost to use, unlike other statistical packages. Due to this, students could continue using the program after their statistical courses and into their professional careers. It would be good to expose students while they are in school to a tool that professionals use in industry. R also has powerful …

New Results In Multivariate Time Series With Applications, Nan Su

All Dissertations

This dissertation presents some new results in stationary multivariate time series.
The asymptotic properties of the sample autocovariance are established, that is, we derive a multivariate version of Bartlett's Classic Formula.
The estimation of the autocovariance function plays a crucial role in time series analysis,
in particular for the identification problem.
Explicit formula for vector autoregressive $(p)$ and vector moving average $(q)$ processes are presented as examples.
We also address linear processes driven by non-independent errors,
a feature that permits consideration of multivariate GARCH processes.
We next compare several techniques to discriminate
two multivariate stationary signals. The compared methods include …

Robust Computational Tools For Multiple Testing With Genetic Association Studies, William L. Welbourn Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The mapping of the human genome and the completion of the Human HapMap project over the past decade have significantly altered how research is conducted with respect to the genetic epidemiology of human disease. Study designs and analytic approaches have evolved rapidly from investigations involving relatively few targeted candidate genes to hypothesis-free genome-wide association studies, where thousands – and now even millions – of single molecular mutations are simultaneously analyzed to identify regions of the genome that may influence disease. As laboratory techniques continue to improve and costs decrease, the volume of genetic data will inexorably rise, and robust tools …

Differential Patterns Of Interaction And Gaussian Graphical Models, Masanao Yajima, Donatello Telesca, Yuan Ji, Peter Muller

COBRA Preprint Series

We propose a methodological framework to assess heterogeneous patterns of association amongst components of a random vector expressed as a Gaussian directed acyclic graph. The proposed framework is likely to be useful when primary interest focuses on potential contrasts characterizing the association structure between known subgroups of a given sample. We provide inferential frameworks as well as an efficient computational algorithm to fit such a model and illustrate its validity through a simulation. We apply the model to Reverse Phase Protein Array data on Acute Myeloid Leukemia patients to show the contrast of association structure between refractory patients and relapsed …

Automated Diagnoses Of Attention Deficit Hyperactive Disorder Using Magnetic Resonance Imaging, Ani Eloyan, John Muschelli, Mary Beth Nebel, Han Liu, Fang Han, Tuo Zhao, Anita Barber, Suresh Joel, James J. Pekar, Stewart Mostofsky, Brian Caffo

Johns Hopkins University, Dept. of Biostatistics Working Papers

Successful automated diagnoses of attention de.cit hyperactive disorder (ADHD) using imaging and functional biomarkers would have fundamental consequences on the public health impact of the disease. In this work, we show results on the predictability of ADHD using imaging biomarkers and discuss the scienti.c and diagnostic impacts of the research. We created a prediction model using the land­mark ADHD 200 data set focusing on resting state functional connectivity (rs-fc) and structural brain imaging. We predicted ADHD status and subtype, obtained by behavioral examination, using imaging data, intelligence quotients and other co­variates. The novel contributions of this manuscript include a thorough …

Perbandingan Tingkat Kepuasan Kerja Perawat Dan Kepuasan Pasien, Jamilla Upik Noras, Ratu Ayu Dewi Sartika

Kesmas

Perawat adalah ujung tombak pemberi pelayanan langsung pada pasien selama 24 jam. Tujuan penelitian adalah untuk membandingkan tingkat kepuasan kerja perawat dengan kepuasan pasien terhadap pelayanan keperawatan kelas 3 di Rumah Sakit Umum Pusat (RSUP) X Jakarta. Penelitian ini bersifat deskriptif dengan desain studi cross sectional, pendekatan kuantitatif dan kualitatif. Populasi adalah seluruh perawat yang bertugas sebagai pelaksana keperawatan kelas 3 sebanyak 40 orang ser- ta pasien yang dirawat di ruang rawat inap kelas 3 sebanyak 120 orang. Pengambilan sampel dilakukan secara purposive sampling sesuai dengan kriteria inklusi dan ekslusi. Hasil pengukuran kuantitatif menunjukkan bah- wa tingkat kepuasan kerja perawat …

A Comparative Analysis Of The Transitional Effect Of Democratic Regime Change On Human Rights Development, Alana Mcelhinney

Honors Capstones

Capstone submitted as a graduation requirement for the BSU Honors Program.

Demographics And Survival Of Aids Cases With Cancer, Washington, Dc, 1996-2006, Heather A. Young, Eric Engels, Anne-Marie Sufian-Kargbo, Alicia Vargas, Kathleen Rogers, Tiffany West, Amanda D. Castel

Epidemiology Faculty Publications

Background

Washington, DC (DC) has one of the highest HIV/AIDS rates in the U.S and cancer is the second leading cause of death among DC residents. This study sought to examine the demographic characteristics and survival of persons with AIDS defining cancers (ADCs) compared to those with non-AIDS defining cancers (NADCs) between the early HAART era (1996-2001) and the late HAART era (2002-2006) in DC.

Methods

Cases reported from 1996-2006 to the DC Cancer Registry and the AIDS Surveillance Registry were linked using a probabilistic matching algorithm. Cases were included if the cancer occurred from 4 months to 60 months …

High And Persistent Hiv Seroincidence In Men Who Have Sex With Men Across 47 U.S. Cities, Marta-Louise Ackers, Alan E. Greenberg, Carol Y. Lin, Bradford N. Bartholow, Adrian Hirsch Goodman, Michael Longhi, Marc Gurwith

Epidemiology Faculty Publications

Objective

To provide HIV seroincidence data among men who have sex with men (MSM) in the United States and to identify predictive factors for seroconversion.

Methods

From 1998–2002, 4684 high-risk MSM, age 18–60 years, participated in a randomized, placebo-controlled HIV vaccine efficacy trial at 56 U.S. clinical trial sites. Demographics, behavioral data, and HIV status were assessed at baseline and 6 month intervals. Since no overall vaccine efficacy was detected, data were combined from both trial arms to calculate HIV incidence based on person-years (py) of follow-up. Predictors of seroconversion, adjusted hazards ratio (aHR), were evaluated using a Cox proportional …

Species Identification And Strain Attribution With Unassembled Sequencing Data, Owen Eric Francis

Theses and Dissertations

Emerging sequencing approaches have revolutionized the way we can collect DNA sequence data for applications in bioforensics and biosurveillance. In this research, we present an approach to construct a database of known biological agents and use this database to develop a statistical framework to analyze raw reads from next-generation sequence data for species identification and strain attribution. Our method capitalizes on a Bayesian statistical framework that accommodates information on sequence quality, mapping quality and provides posterior probabilities of matches to a known database of target genomes. Importantly, our approach also incorporates the possibility that multiple species can be present in …

Hitters Vs. Pitchers: A Comparison Of Fantasy Baseball Player Performances Using Hierarchical Bayesian Models, Scott D. Huddleston

Theses and Dissertations

In recent years, fantasy baseball has seen an explosion in popularity. Major League Baseball, with its long, storied history and the enormous quantity of data available, naturally lends itself to the modern-day recreational activity known as fantasy baseball. Fantasy baseball is a game in which participants manage an imaginary roster of real players and compete against one another using those players' real-life statistics to score points. Early forms of fantasy baseball began in the early 1960s, but beginning in the 1990s, the sport was revolutionized due to the advent of powerful computers and the Internet. The data used in this …

Using An Experimental Mixture Design To Identify Experimental Regions With High Probability Of Creating A Homogeneous Monolithic Column Capable Of Flow, Charles C. Willden

Theses and Dissertations

Graduate students in the Brigham Young University Chemistry Department are working to develop a filtering device that can be used to separate substances into their constituent parts. The device consists of a monomer and water mixture that is polymerized into a monolith inside of a capillary. The ideal monolith is completely solid with interconnected pores that are small enough to cause the constituent parts to pass through the capillary at different rates, effectively separating the substance. Although the end objective is to minimize pore sizes, it is necessary to first identify an experimental region where any combination of input variables …

K-8 Preservice Teachers’ Inductive Reasoning In The Problem-Solving Contexts, Marta Magiera

Mathematics, Statistics and Computer Science Faculty Research and Publications

This paper reports the results from an exploratory study of K-8 pre-service teachers’ inductive reasoning. The analysis of 130 written solutions to seven tasks and 77 reflective journals completed by 20 pre-service teachers lead to descriptions of inductive reasoning processes, i.e. specializing, conjecturing, generalizing, and justifying, in the problem-solving contexts. The uncovered characterizations of the four inductive reasoning processes were further used to describe pathways of successful generalizations. The results highlight the importance of specializing and justifying in constructing powerful generalizations. Implications for teacher education are discussed.

Racial Disparities In Cancer Screening Among Women With Chronic Joint Pain, Edith M. Williams, Laurene Tumiel-Berhalter, Christopher Purdy, Adrianne Ransom, Judith Anderson

Journal of Health Disparities Research and Practice

Chronic pain related disorders and breast and cervical cancer are more prevalent among African-American women compared with non-Hispanic White women. However, few studies address how racial differences in the context of comorbidity may compound these disparities. This study used secondary analysis of the National Health Interview Survey (NHIS) to assess racial differences in breast and cervical cancer screening and patient education among adult women with chronic joint pain conditions. Statistical analyses included chi-square and independent samples t-tests. African-American women compared with non-Hispanic White women were less likely to receive a pap smear or mammogram within the last two years and …

Apartment Rental Prices In Dallas, Mandi Lovett

Undergraduate Research Conference

There are many questions in a graduating students mind such as “Will I get that job?” and “Where will I live?” We wanted to predict apartment rental prices in Dallas to give students an idea of what their living expenses could be. We found that an apartment's distance from downtown Dallas and if the apartment has a pool are two factors that decrease the apartment's overall rental price.