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Articles 17341 - 17370 of 21190

Full-Text Articles in Social and Behavioral Sciences

Bayesian Reliability Modeling Using Monte Carlo Integration, Vincent A. R. Camara, Chris P. Tsokos May 2005

Bayesian Reliability Modeling Using Monte Carlo Integration, Vincent A. R. Camara, Chris P. Tsokos

Journal of Modern Applied Statistical Methods

Bayesian Reliability Modeling Using Monte Carlo IntegrationThe aim of this article is to introduce the concept of Monte Carlo Integration in Bayesian estimation and Bayesian reliability analysis. Using the subject concept, approximate estimates of parameters and reliability functions are obtained for the three-parameter Weibull and the gamma failure models. Four different loss functions are used: square error, Higgins-Tsokos, Harris, and a logarithmic loss function proposed in this article. Relative efficiency is used to compare results obtained under the above mentioned loss functions.

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Exploratory Factor Analysis In Two Measurement Journals: Hegemony By Default, J. Thomas Kellow May 2005

Exploratory Factor Analysis In Two Measurement Journals: Hegemony By Default, J. Thomas Kellow

Journal of Modern Applied Statistical Methods

Exploratory factor analysis studies in two prominent measurement journals were explored. Issues addressed were: (a) factor extraction methods, (b) factor retention rules, (c) factor rotation strategies, and (d) saliency criteria for including variables. Many authors continue to use principal components extraction, orthogonal (varimax) rotation, and retain factors with eigenvalues greater than 1.0.

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An Algorithm For Generating Unconditional Exact Permutation Distribution For A Two-Sample Experiment, Justice I. Odiase, Sunday M. Ogbonmwan May 2005

An Algorithm For Generating Unconditional Exact Permutation Distribution For A Two-Sample Experiment, Justice I. Odiase, Sunday M. Ogbonmwan

Journal of Modern Applied Statistical Methods

An Algorithm that generates the unconditional exact permutation distribution of a 2 x n experiment is presented. The algorithm is able to handle ranks as well as actual observations. It makes it possible to obtain exact p-values for several statistics, especially when sample sizes are small and the application of large sample approximation is unreliable. An illustrative implementation is achieved and leads to the computation of exact p-values for the Mood test when the sample size is small.

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A Comparison Of Nonlinear Regression Codes, Paul Fredrick Mondragon, Brian Borchers May 2005

A Comparison Of Nonlinear Regression Codes, Paul Fredrick Mondragon, Brian Borchers

Journal of Modern Applied Statistical Methods

Five readily available software packages were tested on nonlinear regression test problems from the NIST Statistical Reference Datasets. None of the packages was consistently able to obtain solutions accurate to at least three digits. However, two of the packages were somewhat more reliable than the others.

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Analysis Of Economic Models Through Calculus Of Variations, Raman Arora May 2005

Analysis Of Economic Models Through Calculus Of Variations, Raman Arora

Masters Theses & Specialist Projects

This thesis is a combination of two science fields: Mathematics and Economics. Mathematics is often used to formulate a clear and concise solution to economic problems. In my observation calculus of variation has often been used in various macroeconomic problems. This mathematical method deals with maximizing or minimizing of various objective functions given a set of constraints. This topic brings out one of the best ways to show the relationship between mathematics and economics. My thesis consists of three parts: The first chapter contains a review of the calculus of variations. Basic definitions and important conditions have been stated. The …

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A Multi-Scale Analysis Of Census-Based Land Surface Temperature Variations And Determinants In Indianapolis, Indiana, Bingqing Liang May 2005

A Multi-Scale Analysis Of Census-Based Land Surface Temperature Variations And Determinants In Indianapolis, Indiana, Bingqing Liang

All-Inclusive List of Electronic Theses and Dissertations

Mapping urban temperatures are one of the major foci in urban climatology studies due to its close relationships with environmental, economic, and social issues. Most previous urban temperature studies were based on a single scale. This study utilized remote sensing and GIS data to perform a multiple scale analysis of urban temperatures. Land surface temperatures (LST) data derived from a Landsat Enhanced Thematic Mapper Plus (ETM+) image were used to examine census-based variations and to model their numerical relationships with urban morphology in Marion County, Indiana. Selected variables for the urban morphology include Normalized Difference Vegetation Index (NOVI), buildings, roads, …

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An Investigation Of Recycling Habits Of Pet (E) Bottles In The Terre Haute Area, Alexander J. Hagedorn May 2005

An Investigation Of Recycling Habits Of Pet (E) Bottles In The Terre Haute Area, Alexander J. Hagedorn

All-Inclusive List of Electronic Theses and Dissertations

This research investigated recycling habits of PET (E) water and soft drink bottles in the Terre Haute area. The purpose of this research will be to determine the general recycling habits in the Terre Haute area. It allowed the researcher to examine specified areas within Terre Haute. The data was statistically analyzed to determine if age, gender, race, income, location have any influence on recycling behavior. The data for this research was obtained through a survey conducted at various locations.

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An Ontological Approach To The Document Access Problem Of Insider Threat, Boanerges Aleman-Meza, Phillip Burns, Matthew Eavenson, Devanand Palanswami, Amit P. Sheth May 2005

An Ontological Approach To The Document Access Problem Of Insider Threat, Boanerges Aleman-Meza, Phillip Burns, Matthew Eavenson, Devanand Palanswami, Amit P. Sheth

Kno.e.sis Publications

Verification of legitimate access of documents, which is one aspect of the umbrella of problems in the Insider Threat category, is a challenging problem. This paper describes the research and prototyping of a system that takes an ontological approach, and is primarily targeted for use by theintelligence community. Our approach utilizes the notion of semantic associations and their discovery among a collection of heterogeneous documents. We highlight our contributions in (graphically) capturing the scope of the investigation assignment of an intelligence analyst by referring to classes and relationships of an ontology; in computing a measure of the relevance …

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The Effect Of Scaling-Up On Remotely Derived Leaf Area Index Estimators In The Brazilian Amazon, John I. Menzies May 2005

The Effect Of Scaling-Up On Remotely Derived Leaf Area Index Estimators In The Brazilian Amazon, John I. Menzies

All-Inclusive List of Electronic Theses and Dissertations

This research compared a traditional statistical technique with artificial neural networks to determine their effectiveness for modeling LAI in the Santarem region of the Brazilian Amazon. In addition, different satellite sensors in the form of ETM+, ASTER, MO DIS, and IKONOS were used to assess if spatial and spectral resolutions play a role in the ability to estimate LAI. This study focused on the following: (1) Determining if neural networks perform more accurately than multiple regression for LAI modeling (2) the effectiveness of different resolution satellite data including ETM+, ASTER, MODIS, and IKONOS for LAI estimation; (3) determining if spatial …

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Semantic Web Services For N-Glycosylation Process, Satya S. Sahoo, Amit P. Sheth, William S. York, John A. Miller May 2005

Semantic Web Services For N-Glycosylation Process, Satya S. Sahoo, Amit P. Sheth, William S. York, John A. Miller

Kno.e.sis Publications

Glycomics is one of the many research efforts currently underway in the biosciences domain, which is characterized by high throughput data generated at multiple experimental stages. For example, analysis of N-glycosylation encompasses stages from cell-culture to peptide identification and quantification. Research groups across the world use diverse cell cultures, separation and spectroscopic techniques, and data identification, correlation and integration methodologies. Thus, data generated at different phases of the process by multiple groups are both structurally and functionally heterogeneous.

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Bias Of The Cox Model Hazard Ratio, Inger Persson, Harry Khamis May 2005

Bias Of The Cox Model Hazard Ratio, Inger Persson, Harry Khamis

Journal of Modern Applied Statistical Methods

The hazard ratio estimated with the Cox model is investigated under proportional and five forms of nonproportional hazards. Results indicate that the highest bias occurs for diverging hazards with early censoring, and for increasing and crossing hazards under a high censoring rate.

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Bias Affiliated With Two Variants Of Cohen’S D When Determining U1 As A Measure Of The Percent Of Non-Overlap, David A. Walker May 2005

Bias Affiliated With Two Variants Of Cohen’S D When Determining U1 As A Measure Of The Percent Of Non-Overlap, David A. Walker

Journal of Modern Applied Statistical Methods

Variants of Cohen’s d, in this instance dt and dadj, has the largest influence on U1 measures used with smaller sample sizes, specifically when n1 and n2 = 10. This study indicated that bias for variants of d, which influence U1 measures, tends to subside and become more manageable, in terms of precision of estimation, around 1% to 2% when n1 and n2 = 20. Thus, depending on the direction of the influence, both dt and dadj are likely to manage bias in the U1 measure quite well for smaller to …

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Some Guidelines For Using Nonparametric Methods For Modeling Data From Response Surface Designs, Christine M. Anderson-Cook, Kathryn Prewitt May 2005

Some Guidelines For Using Nonparametric Methods For Modeling Data From Response Surface Designs, Christine M. Anderson-Cook, Kathryn Prewitt

Journal of Modern Applied Statistical Methods

Traditional response surface methodology focuses on modeling responses using parametric models with designs chosen to balance cost with adequate estimation of parameters and prediction in the design space. Using nonparametric smoothing to approximate the response surface offers both opportunities as well as problems. This article explores some conditions under which these methods can be appropriately used to increase the flexibility of surfaces modeled. The Box and Draper (1987) printing ink study is considered to illustrate the methods.

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Determining The Correct Number Of Components To Extract From A Principal Components Analysis: A Monte Carlo Study Of The Accuracy Of The Scree Plot, Gibbs Y. Kanyongo May 2005

Determining The Correct Number Of Components To Extract From A Principal Components Analysis: A Monte Carlo Study Of The Accuracy Of The Scree Plot, Gibbs Y. Kanyongo

Journal of Modern Applied Statistical Methods

This article pertains to the accuracy of the of the scree plot in determining the correct number of components to retain under different conditions of sample size, component loading and variable-tocomponent ratio. The study employs use of Monte Carlo simulations in which the population parameters were manipulated, and data were generated, and then the scree plot applied to the generated scores.

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Bayesian Wavelet Estimation Of Long Memory Parameter, Leming Qu May 2005

Bayesian Wavelet Estimation Of Long Memory Parameter, Leming Qu

Journal of Modern Applied Statistical Methods

A Bayesian wavelet estimation method for estimating parameters of a stationary I(d) process is represented as an useful alternative to the existing frequentist wavelet estimation methods. The effectiveness of the proposed method is demonstrated through Monte Carlo simulations. The sampling from the posterior distribution is through the Markov Chain Monte Carlo (MCMC) easily implemented in the WinBUGS software package.

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Enhancing The Performance Of A Short Run Multivariate Control Chart For The Process Mean, Michael B. C. Khoo, T. F. Ng May 2005

Enhancing The Performance Of A Short Run Multivariate Control Chart For The Process Mean, Michael B. C. Khoo, T. F. Ng

Journal of Modern Applied Statistical Methods

No abstract provided.

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Jmasm16: Pseudo-Random Number Generation In R For Some Univariate Distributions, Hakan Demirtas May 2005

Jmasm16: Pseudo-Random Number Generation In R For Some Univariate Distributions, Hakan Demirtas

Journal of Modern Applied Statistical Methods

An increasing number of practitioners and applied researchers started using the R programming system in recent years for their computing and data analysis needs. As far as pseudo-random number generation is concerned, the built-in generator in R does not contain some important univariate distributions. In this article, complementary R routines that could potentially be useful for simulation and computation purposes are provided.

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Jmasm17: An Algorithm And Code For Computing Exact Critical Values For Friedman’S Nonparametric Anova, Sikha Bagui, Sbuhash Bagui May 2005

Jmasm17: An Algorithm And Code For Computing Exact Critical Values For Friedman’S Nonparametric Anova, Sikha Bagui, Sbuhash Bagui

Journal of Modern Applied Statistical Methods

Provided in this article is an algorithm and code for computing exact critical values (or percentiles) for Friedman’s nonparametric rank test for k related treatment populations using Visual Basic (VB.NET). This program has the ability to calculate critical values for any number of treatment populations ( k ) and block sizes (b) at any significance level (α ) . We developed an exact critical value table for k = 2(1)5 and b = 2(1)15. This table will be useful to practitioners since it is not available in standard nonparametric statistics texts. The program can also be used to compute any …

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Jmasm19: A Spss Matrix For Determining Effect Sizes From Three Categories: R And Functions Of R, Differences Between Proportions, And Standardized Differences Between Means, David A. Walker May 2005

Jmasm19: A Spss Matrix For Determining Effect Sizes From Three Categories: R And Functions Of R, Differences Between Proportions, And Standardized Differences Between Means, David A. Walker

Journal of Modern Applied Statistical Methods

The program is intended to provide editors, manuscript reviewers, students, and researchers with an SPSS matrix to determine an array of effect sizes not reported or the correctness of those reported, such as rrelated indices, r-related squared indices, and measures of association, when the only data provided in the manuscript or article are the n, M, and SD (and sometimes proportions and t and F (1) values) for twogroup designs. This program can create an internal matrix table to assist researchers in determining the size of an effect for commonly utilized r-related, mean difference, and difference in proportions indices when …

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Letter To The Editor, Jmasm Editors May 2005

Letter To The Editor, Jmasm Editors

Journal of Modern Applied Statistical Methods

No abstract provided.

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Boston Harbor Islands Renewables Planning Guide, Urban Harbors Institute, University Of Massachusetts Boston, Island Alliance May 2005

Boston Harbor Islands Renewables Planning Guide, Urban Harbors Institute, University Of Massachusetts Boston, Island Alliance

Urban Harbors Institute Publications

This document presents a summary of findings and recommendations from a predevelopment study of the feasibility of establishing renewable energy power generation on several of the grid-tied Boston Harbor Islands. The scope of the study was to investigate the factors and issues associated with installing a mix of renewables — wind, solar, wave and tidal/current power generating facilities — with a combined output of between one and ten megawatts at sites on or around five of the Boston Harbor Islands. Four of these islands are presently grid-tied: Long Island, Moon Island, Spectacle Island, and Thompson Island. A fifth island, Peddocks …

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An Exploration Of Using Data Mining In Educational Research, Yonghong Jade Xu May 2005

An Exploration Of Using Data Mining In Educational Research, Yonghong Jade Xu

Journal of Modern Applied Statistical Methods

Technology advances popularized large databases in education. Traditional statistics have limitations for analyzing large quantities of data. This article discusses data mining by analyzing a data set with three models: multiple regression, data mining, and a combination of the two. It is concluded that data mining is applicable in educational research.

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Effect Of Position Of An Outlier On The Influence Curve Of The Measures Of Preferred Direction For Circular Data, B. Sango Otieno, Christine M. Anderson-Cook May 2005

Effect Of Position Of An Outlier On The Influence Curve Of The Measures Of Preferred Direction For Circular Data, B. Sango Otieno, Christine M. Anderson-Cook

Journal of Modern Applied Statistical Methods

Circular or angular data occur in many fields of applied statistics. A common problem of interest in circular data is estimating a preferred direction and its corresponding distribution. It is complicated by the wrap-around effect on the circle, which exists because there is no natural minimum or maximum. The usual statistics employed for linear data are inappropriate for directional data, as they do not account for its circular nature. The robustness of the three common choices for summarizing the preferred direction (the sample circular mean, sample circular median and a circular analog of the Hodges-Lehmann estimator) are evaluated via their …

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An Empirical Evaluation Of The Retrospective Pretest: Are There Advantages To Looking Back?, Paul A. Nakonezny, Joseph Lee Rodgers May 2005

An Empirical Evaluation Of The Retrospective Pretest: Are There Advantages To Looking Back?, Paul A. Nakonezny, Joseph Lee Rodgers

Journal of Modern Applied Statistical Methods

This article builds on research regarding response shift effects and retrospective self-report ratings. Results suggest moderate evidence of a response shift bias in the conventional pretest-posttest treatment design in the treatment group. The use of explicitly worded anchors on response scales, as well as the measurement of knowledge ratings (a cognitive construct) in an evaluation methodology setting, helped to mitigate the magnitude of a response shift bias. The retrospective pretest-posttest design provides a measure of change that is more in accord with the objective measure of change than is the conventional pretest-posttest treatment design with the objective measure of change, …

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Regression By Data Segments Via Discriminant Analysis, Stan Lipovetsky, Michael Conklin May 2005

Regression By Data Segments Via Discriminant Analysis, Stan Lipovetsky, Michael Conklin

Journal of Modern Applied Statistical Methods

It is known that two-group linear discriminant function can be constructed via binary regression. In this article, it is shown that the opposite relation is also relevant – it is possible to present multiple regression as a linear combination of a main part, based on the pooled variance, and Fisher discriminators by data segments. Presenting regression as an aggregate of the discriminators allows one to decompose coefficients of the model into sum of several vectors related to segments. Using this technique provides an understanding of how the total regression model is composed of the regressions by the segments with possible …

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Inferences About Regression Interactions Via A Robust Smoother With An Application To Cannabis Problems, Rand R. Wilcox, Mitchell Earleywine May 2005

Inferences About Regression Interactions Via A Robust Smoother With An Application To Cannabis Problems, Rand R. Wilcox, Mitchell Earleywine

Journal of Modern Applied Statistical Methods

A flexible approach to testing the hypothesis of no regression interaction is to test the hypothesis that a generalized additive model provides a good fit to the data, where the components are some type of robust smoother. A practical concern, however, is that there are no published results on how well this approach controls the probability of a Type I error. Simulation results, reported here, indicate that an appropriate choice for the span of the smoother is required so that the actual probability of a Type I error is reasonably close to the nominal level. The technique is illustrated with …

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Local Power For Combining Independent Tests In The Presence Of Nuisance Parameters For The Logistic Distribution, Walid A. Abu-Dayyeh, Z. R. Al-Rawi, M. M. A. Al-Momani May 2005

Local Power For Combining Independent Tests In The Presence Of Nuisance Parameters For The Logistic Distribution, Walid A. Abu-Dayyeh, Z. R. Al-Rawi, M. M. A. Al-Momani

Journal of Modern Applied Statistical Methods

Four combination methods of independent tests for testing a simple hypothesis versus one-sided alternative are considered viz. Fisher, the logistic, the sum of P-values and the inverse normal method in case of logistic distribution. These methods are compared via local power in the presence of nuisance parameters for some values of α using simple random sample.

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Hand-Held Calculators And Mathematics Achievement: What The 1996 National Assessment Of Educational Progress Eighth-Grade Mathematics Exam Scores Tell Us, Kenneth L. Wareham May 2005

Hand-Held Calculators And Mathematics Achievement: What The 1996 National Assessment Of Educational Progress Eighth-Grade Mathematics Exam Scores Tell Us, Kenneth L. Wareham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to analyze the 1996 National Assessment of Educational Progress data to identify the relationship between calculator use and student performance on the National Assessment of Educational Progress Mathematics Assessment. This general purpose includes several sub issues. In addition to being interested in the overall relationship between use and National Assessment of Educational Progress achievement (including the effort to control for spurious factors), this study examined the contextual factors that moderate the impact of calculator use. Similarly, it analyzed the relationship between calculator use and student performance on calculator-allowed and calculator-restricted items, as well as …

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Inside Unlv, Erin O'Donnell, Diane Russell, Carol C. Harter May 2005

Inside Unlv, Erin O'Donnell, Diane Russell, Carol C. Harter

Inside UNLV

No abstract provided.

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Streamlining The National Environmental Policy Act Reporting Requirements: A Hard Look At The Healthy Forests Initiative, Jeffrey Alan Geller May 2005

Streamlining The National Environmental Policy Act Reporting Requirements: A Hard Look At The Healthy Forests Initiative, Jeffrey Alan Geller

UNLV Theses, Dissertations, Professional Papers, and Capstones

The U.S. Forest Service (USFS) has implemented the Healthy Forests Initiative (HFI) (2002), which streamlines the NEPA process for proposed forest fuel reduction projects. A key question is whether the USFS’s streamlined NEPA process produces an adequate environmental document and fulfills regulatory requirements. This thesis evaluates whether the streamlined approach practiced by the USFS under the HFI satisfies the NEPA requirements. A review of four streamlined documents assesses whether these requirements are met. The following NEPA requirements in particular are explored for each project to determine whether the NEPA requirements are met: consideration of a reasonable range of alternatives to …

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