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2005

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Articles 2161 - 2190 of 5573

Full-Text Articles in Physical Sciences and Mathematics

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 21, Number 8, May 2005, College Of Engineering And Computer Science, Wright State University May 2005

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 21, Number 8, May 2005, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

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Measuring Inter-Rater Agreement Among Pathologists In Cancer Screening Studies, Krystle S. Oates May 2005

Measuring Inter-Rater Agreement Among Pathologists In Cancer Screening Studies, Krystle S. Oates

Electronic Dissertations and Theses

Although cervical cancer is one of the most preventable forms of cancer in the United States, it still remains the leading cause of cancer mortality in El Salvador. This is attributed to poor cancer screening in El Salvador. The Pap smear test is the traditional screening method that pathologists use for the direction of cervical cancer in women, but the Thin Prep test is said to be an improvement to the Prep smear test. In this project, we will use the data from pathologists in the United States and El Salvador who analyzed the slides of 471 Salvadoran women who …

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Dynamic Modification Of Basic Input/Output System Attributes Via The Operating System For Intel X86 Architecture Personal Computers, Jabari R. Roberts May 2005

Dynamic Modification Of Basic Input/Output System Attributes Via The Operating System For Intel X86 Architecture Personal Computers, Jabari R. Roberts

Electronic Dissertations and Theses

Currently in the world, computers are used in order to do numerous actions to benefits humanity at large. Part of the computer power is used within the realm of personal computer workstations, which is the most widely used type of computer. However, in a lot of ways, the current computer is inefficient. Much of the computer-buying populace buy newer computer systems that scientists in the 1970s and 1980s could only dream of but use an average of only 20-30% of its full processing capabilities during its operation. In other words, many beginner and novice users simply don't use its full …

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Dynamic Modification Of Basic Input/Output System Attributes Via The Operating System For Intel X86 Architecture Personal Computers, Jabari R. Roberts May 2005

Dynamic Modification Of Basic Input/Output System Attributes Via The Operating System For Intel X86 Architecture Personal Computers, Jabari R. Roberts

Electronic Dissertations and Theses

Currently in the world, computers are used in order to do numerous actions to benefit humanity at large. Part of the computer power is used within the realm of personal computers workstations, which is the most widely used type of computer. However, in a lot of ways, the current computer is inefficient. Much of the computer buying populace buy newer computer systems that scientists in the 1970s and 1980s could only dream of but use an average of only 20-30% of its full processing capabilities during its operation. In other words, many beginner and novice users simply don't use its …

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The Effects Of Bell Vibrations On The Sound Of The Modern Trumpet, Thomas R. Moore, Erin T. Shirley, Isaac E. W. Codrey, Amy E. Daniels May 2005

The Effects Of Bell Vibrations On The Sound Of The Modern Trumpet, Thomas R. Moore, Erin T. Shirley, Isaac E. W. Codrey, Amy E. Daniels

Student-Faculty Collaborative Research Publications

The acoustic spectrum of a modern trumpet with the bell section heavily damped has been compared to the spectrum of the same instrument with the bell section left free to vibrate. Measurements of the amplitude of vibration indicate that the damping significantly reduces the movement of the metal, and a corresponding change in the acoustic spectrum between the two cases is found. It is shown that the relative power in the fundamental may change by more than 3 dB when the vibrations in the bell section are damped. Two possible causes for the effects are considered: a change in input …

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On The Nature Of Connectivity Types, Miao Xu May 2005

On The Nature Of Connectivity Types, Miao Xu

Honors Theses

No abstract provided.

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Dynamical Systems And The Logistic And Tent Maps, Kathleen Larkin Spires May 2005

Dynamical Systems And The Logistic And Tent Maps, Kathleen Larkin Spires

Honors Theses

No abstract provided.

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Magnetic And Electrical Properties Of Single-Phase Multiferroic Bifeo3, Aswini K. Pradhan, Kai Zhang, D. Hunter, J.B. Dadson, G.B. Loiutts, P. Bhattacharya, R. Katiyar, Jun Zhang, David J. Sellmyer, U.N. Roy, Y. Cui, A. Burger May 2005

Magnetic And Electrical Properties Of Single-Phase Multiferroic Bifeo3, Aswini K. Pradhan, Kai Zhang, D. Hunter, J.B. Dadson, G.B. Loiutts, P. Bhattacharya, R. Katiyar, Jun Zhang, David J. Sellmyer, U.N. Roy, Y. Cui, A. Burger

David Sellmyer Publications

We have reported the structural, thermal, microscopic, magnetization, polarization, and dielectric properties of BiFeO3 ceramics synthesized by a rapid liquid-phase sintering technique. Optimum conditions for the synthesis of single-phase BiFeO3 ceramics were obtained. Temperature-dependent magnetization and hysteresis loops indicate antiferromagnetic behavior in BiFeO3 at room temperature. Although saturated ferroelectric hysteresis loops were observed in single-phase BiFeO3 ceramic synthesized at 880 °C, the reduced polarization is found to be due to the high loss and low dielectric permittivity of the ceramic, which is caused by higher leakage current.

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Nine-Banded Armadillo (Dasypus Novemcinctus), Michael T. Mengak May 2005

Nine-Banded Armadillo (Dasypus Novemcinctus), Michael T. Mengak

Other Publications in Wildlife Management

Scientists classify armadillos with anteaters and sloths which tells us immediately that they have poorly developed teeth and limited mobility. Armadillos have small, peg-like teeth that are useful for grinding their food but of little value for capturing prey. No other mammal in Georgia has bony skin plates which makes the armadillo easy to identify. Their common name, armadillo, is derived from a Spanish term meaning “little armored one”. The nine-banded part of their name refers to the nine flexible plates that comprise their shell. Just like a turtle, the shell is called a carapace.

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Within By Within Anova Based On Medians, Rand R. Wilcox May 2005

Within By Within Anova Based On Medians, Rand R. Wilcox

Journal of Modern Applied Statistical Methods

This article considers a J by K ANOVA design where all JK groups are dependent and where groups are to be compared based on medians. Two general approaches are considered. The first is based on an omnibus test for no main effects and no interactions and the other tests each member of a collection of relevant linear contrasts. Based on an earlier paper dealing with multiple comparisons, an obvious speculation is that a particular bootstrap method should be used. One of the main points here is that, in general, this is not the case for the problem at hand. The …

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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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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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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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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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Testing The Casual Relation Between Sunspots And Temperature Using Wavelets Analysis, Abdullah Almasri, Ghazi Shukur May 2005

Testing The Casual Relation Between Sunspots And Temperature Using Wavelets Analysis, Abdullah Almasri, Ghazi Shukur

Journal of Modern Applied Statistical Methods

Investigated and tested in this article are the causal nexus between sunspots and temperature by using statistical methodology and causality tests. Because this kind of relationship cannot be properly captured in the short run (daily, monthly or yearly data), the relationship is investigated in the long run using a very low frequency Wavelets-based decomposed data such as D8 (128 - 256 months). Results indicate that during the period 1854-1989, the causality nexus between these two series is as expected of onedirectional form, i.e., from sunspots to temperature.

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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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Model-Selection-Based Monitoring Of Structural Change, Kosei Fukuda May 2005

Model-Selection-Based Monitoring Of Structural Change, Kosei Fukuda

Journal of Modern Applied Statistical Methods

Monitoring structural change is performed not by hypothesis testing but by model selection using a modified Bayesian information criterion. It is found that concerning detection accuracy and detection speed, the proposed method shows better performance than the hypothesis-testing method. Two advantages of the proposed method are also discussed.

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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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Using Scale Mixtures Of Normals To Model Continuously Compounded Returns, Hasan Hamdan, John Nolan, Melanie Wilson, Kristen Dardia May 2005

Using Scale Mixtures Of Normals To Model Continuously Compounded Returns, Hasan Hamdan, John Nolan, Melanie Wilson, Kristen Dardia

Journal of Modern Applied Statistical Methods

A new method for estimating the parameters of scale mixtures of normals (SMN) is introduced and evaluated. The new method is called UNMIX and is based on minimizing the weighted square distance between exact values of the density of the scale mixture and estimated values using kernel smoothing techniques over a specified grid of x-values and a grid of potential scale values. Applications of the method are made in modeling the continuously compounded return, CCR, of stock prices. Modeling this ratio with UNMIX proves promising in comparison with other existing techniques that use only one normal component, or those that …

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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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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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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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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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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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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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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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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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Abelson’S Paradox And The Michelson-Morley Experiment, Shlomo S. Sawilowsky May 2005

Abelson’S Paradox And The Michelson-Morley Experiment, Shlomo S. Sawilowsky

Theoretical and Behavioral Foundations of Education Faculty Publications

No abstract provided.

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