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Physical Sciences and Mathematics Commons™

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Theses/Dissertations

Statistics and Probability

Brigham Young University

2006

Articles 1 - 10 of 10

Full-Text Articles in Physical Sciences and Mathematics

Life Data Analysis Of Repairable Systems: A Case Study On Brigham Young University Media Rooms, Stephen Oluaku Manortey Dec 2006

Life Data Analysis Of Repairable Systems: A Case Study On Brigham Young University Media Rooms, Stephen Oluaku Manortey

Theses and Dissertations

It is an undisputable fact that most systems, upon consistence usage are bound to fail in the performance of their intended functions at a point in time. When this occurs, various strategies are set in place to restore them back to a satisfactory performance. This may include replacing the failed component with a new one, swapping parts, resetting adjustable parts to mention but a few. Any such system is referred to as a repairable system. There is the need to study these systems and use statistical models to predict their failing time and be able to set modalities in place …

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A Comparison Of Microarray Analyses: A Mixed Models Approach Versus The Significance Analysis Of Microarrays, Nathan Wallace Stephens Nov 2006

A Comparison Of Microarray Analyses: A Mixed Models Approach Versus The Significance Analysis Of Microarrays, Nathan Wallace Stephens

Theses and Dissertations

DNA microarrays are a relatively new technology for assessing the expression levels of thousands of genes simultaneously. Researchers hope to find genes that are differentially expressed by hybridizing cDNA from known treatment sources with various genes spotted on the microarrays. The large number of tests involved in analyzing microarrays has raised new questions in multiple testing. Several approaches for identifying differentially expressed genes have been proposed. This paper considers two: (1) a mixed models approach, and (2) the Signiffcance Analysis of Microarrays.

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A Logistic Regression Analysis Of Utah Colleges Exit Poll Response Rates Using Sas Software, Clint W. Stevenson Oct 2006

A Logistic Regression Analysis Of Utah Colleges Exit Poll Response Rates Using Sas Software, Clint W. Stevenson

Theses and Dissertations

In this study I examine voter response at an interview level using a dataset of 7562 voter contacts (including responses and nonresponses) in the 2004 Utah Colleges Exit Poll. In 2004, 4908 of the 7562 voters approached responded to the exit poll for an overall response rate of 65 percent. Logistic regression is used to estimate factors that contribute to a success or failure of each interview attempt. This logistic regression model uses interviewer characteristics, voter characteristics (both respondents and nonrespondents), and exogenous factors as independent variables. Voter characteristics such as race, gender, and age are strongly associated with response. …

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Sources Of Variability In A Proteomic Experiment, Scott Daniel Crawford Aug 2006

Sources Of Variability In A Proteomic Experiment, Scott Daniel Crawford

Theses and Dissertations

The study of proteomics holds the hope for detecting serious diseases earlier than is currently possible by analyzing blood samples in a mass spectrometer. Unfortunately, the statistics involved in comparing a control group to a diseased group are not trivial, and these difficulties have led others to incorrect decisions in the past. This paper considers a nested design that was used to quantify and identify the sources of variation in the mass spectrometer at BYU, so that correct conclusions can be drawn from blood samples analyzed in proteomics. Algorithms were developed which detect, align, correct, and cluster the peaks in …

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Understanding Brigham Young University's Technology Teacher Education Program's Sucess In Attracting And Retaining Female Students, Katrina M. Cox Jul 2006

Understanding Brigham Young University's Technology Teacher Education Program's Sucess In Attracting And Retaining Female Students, Katrina M. Cox

Theses and Dissertations

The purpose of the study was to attempt to understand why Brigham Young University Technology Teacher Education program has attracted and retained a high number of females. This was done through a self-created survey composed of four forced responses, distributed among the Winter 2006 semester students. Likert-scale questions were outlined according to the five theoretical influences on women in technology, as established by Welty and Puck (2001) and two of the three relationships of academia, as established by Haynie III (1999), as well as three free response questions regarding retention and attraction within the major. Findings suggested strong positive polarity …

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Computation Of Weights For Probabilistic Record Linkage Using The Em Algorithm, G. John Bauman Jun 2006

Computation Of Weights For Probabilistic Record Linkage Using The Em Algorithm, G. John Bauman

Theses and Dissertations

Record linkage is the process of combining information about a single individual from two or more records. Probabilistic record linkage gives weights to each field that is compared. The decision of whether the records should be linked is then determined by the sum of the weights, or “Score”, over all fields compared. Using methods similar to the simple versus simple most powerful test, an optimal record linkage decision rule can be established to minimize the number of unlinked records when the probability of false positive and false negative errors are specified. The weights needed for probabilistic record linkage necessitate linking …

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Food Shelf Life: Estimation And Experimental Design, Ross Allen Andrew Larsen May 2006

Food Shelf Life: Estimation And Experimental Design, Ross Allen Andrew Larsen

Theses and Dissertations

Shelf life is a parameter of the lifetime distribution of a food product, usually the time until a specified proportion (1-50%) of the product has spoiled according to taste. The data used to estimate shelf life typically come from a planned experiment with sampled food items observed at specified times. The observation times are usually selected adaptively using ‘staggered sampling.’ Ad-hoc methods based on linear regression have been recommended to estimate shelf life. However, other methods based on maximizing a likelihood (MLE) have been proposed, studied, and used. Both methods assume the Weibull distribution. The observed lifetimes in shelf life …

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Bayesian And Positive Matrix Factorization Approaches To Pollution Source Apportionment, Jeff William Lingwall May 2006

Bayesian And Positive Matrix Factorization Approaches To Pollution Source Apportionment, Jeff William Lingwall

Theses and Dissertations

The use of Positive Matrix Factorization (PMF) in pollution source apportionment (PSA) is examined and illustrated. A study of its settings is conducted in order to optimize them in the context of PSA. The use of a priori information in PMF is examined, in the form of target factor profiles and pulling profile elements to zero. A Bayesian model using lognormal prior distributions for source profiles and source contributions is fit and examined.

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Modeling The Performance Of A Baseball Player's Offensive Production, Michael Ross Smith Mar 2006

Modeling The Performance Of A Baseball Player's Offensive Production, Michael Ross Smith

Theses and Dissertations

This project addresses the problem of comparing the offensive abilities of players from different eras in Major League Baseball (MLB). We will study players from the perspective of an overall offensive summary statistic that is highly linked with scoring runs, or the Berry Value. We will build an additive model to estimate the innate ability of the player, the effect of the relative level of competition of each season, and the effect of age on performance using piecewise age curves. Using Hierarchical Bayes methodology with Gibbs sampling, we model each of these effects for each individual. The results of the …

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Correlating Factors Between Student Participation And Student Learning Via A Service Learning Project In Secondary Education: A Case Study, Shawn V. Jensen Jan 2006

Correlating Factors Between Student Participation And Student Learning Via A Service Learning Project In Secondary Education: A Case Study, Shawn V. Jensen

Theses and Dissertations

In this study a service-learning project was conducted with secondary students in a construction technology based course. Three research questions were considered; (1) does service learning projects help to engage student participation, (2) can students learn the course curriculum while participating in a service learning project, and (3) is there a correlation between student participation and student learning as it pertains to service learning projects? The data was collected through surveys, observations, interviews, and evaluations. The researcher concluded the following from the study; 92% of the students were actively participating in the two week service project, 76% of the students …

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