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Mathematical Programming Approaches to the Three-Group Classification Problem

Description: In the last twelve years there has been considerable research interest in mathematical programming approaches to the statistical classification problem, primarily because they are not based on the assumptions of the parametric methods (Fisher's linear discriminant function, Smith's quadratic discriminant function) for optimality. This dissertation focuses on the development of mathematical programming models for the three-group classification problem and examines the computational efficiency an… more
Date: August 1993
Creator: Loucopoulos, Constantine
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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The Effect of Psychometric Parallelism among Predictors on the Efficiency of Equal Weights and Least Squares Weights in Multiple Regression

Description: There are several conditions for applying equal weights as an alternative to least squares weights. Psychometric parallelism, one of the conditions, has been suggested as a necessary and sufficient condition for equal-weights aggregation. The purpose of this study is to investigate the effect of psychometric parallelism among predictors on the efficiency of equal weights and least squares weights. Target correlation matrices with 10,000 cases were simulated so that the matrices had varying degr… more
Date: May 1996
Creator: Zhang, Desheng
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Measurement Disturbance Effects on Rasch Fit Statistics and the Logit Residual Index

Description: The effects of random guessing as a measurement disturbance on Rasch fit statistics (unweighted total, weighted total, and unweighted ability between) and the Logit Residual Index (LRI) were examined through simulated data sets of varying sample sizes, test lengths, and distribution types. Three test lengths (25, 50, and 100), three sample sizes (25, 50, and 100), two item difficulty distributions (normal and uniform), and three levels of guessing (no guessing (0%), 25%, and 50%) were used in t… more
Date: August 1997
Creator: Mount, Robert E. (Robert Earl)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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An entropic approach to the analysis of time series.

Description: Statistical analysis of time series. With compelling arguments we show that the Diffusion Entropy Analysis (DEA) is the only method of the literature of the Science of Complexity that correctly determines the scaling hidden within a time series reflecting a Complex Process. The time series is thought of as a source of fluctuations, and the DEA is based on the Shannon entropy of the diffusion process generated by these fluctuations. All traditional methods of scaling analysis, instead, are base… more
Date: December 2001
Creator: Scafetta, Nicola
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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A Monte Carlo Study of the Robustness and Power Associated with Selected Tests of Variance Equality when Distributions are Non-Normal and Dissimilar in Form

Description: When selecting a method for testing variance equality, a researcher should select a method which is robust to distribution non-normality and dissimilarity. The method should also possess sufficient power to ascertain departures from the equal variance hypothesis. This Monte Carlo study examined the robustness and power of five tests of variance equality under specific conditions. The tests examined included one procedure proposed by O'Brien (1978), two by O'Brien (1979), and two by Conover, Jo… more
Date: August 1990
Creator: Hardy, James C. (James Clifford)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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An Investigation into the Effectiveness of Intelligent Tutoring on Learning of College Level Statistics

Description: The present research incorporated the content of basic statistics into the Artificial Intelligence Physics Tutor (ARPHY), which was used as the expert system shell, and investigated the effects of the Artificial Intelligent Statistics Tutor (ARSTAT) as a supplement to learning statistics at the college level. Two classes of an introductory educational statistics course in the Department of Educational Foundations, University of North Texas, were used in the study. The daytime class was used as … more
Date: May 1989
Creator: Palitawanont, Nanta
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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An Empirical Comparison of Random Number Generators: Period, Structure, Correlation, Density, and Efficiency

Description: Random number generators (RNGs) are widely used in conducting Monte Carlo simulation studies, which are important in the field of statistics for comparing power, mean differences, or distribution shapes between statistical approaches. Statistical results, however, may differ when different random number generators are used. Often older methods have been blindly used with no understanding of their limitations. Many random functions supplied with computers today have been found to be comparativel… more
Date: August 1995
Creator: Bang, Jung Woong
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Robustness of the One-Sample Kolmogorov Test to Sampling from a Finite Discrete Population

Description: One of the most useful and best known goodness of fit test is the Kolmogorov one-sample test. The assumptions for the Kolmogorov (one-sample test) test are: 1. A random sample; 2. A continuous random variable; 3. F(x) is a completely specified hypothesized cumulative distribution function. The Kolmogorov one-sample test has a wide range of applications. Knowing the effect fromusing the test when an assumption is not met is of practical importance. The purpose of this research is to analyze the … more
Date: December 1996
Creator: Tucker, Joanne M. (Joanne Morris)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
open access

Structural Causes of Transnational Terrorism: a Cross-National Longitudinal Analysis

Description: This study provides a first attempt at building a multivariate model to explain terrorist activity by including six national factors proposed to have a relationship to the number of terrorist events occurring in a given nation and the number of terrorist incidents attributed to groups primarily identified with a given nation. These factors include rate of population growth, level of economic development, economic growth rate, level of democracy, presence of leftist regime type, and level of rep… more
Date: August 1994
Creator: Wendel, Dierdre L. (Dierdre Lynelle)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Characterizing Spontaneous Neurophysiological Activity with Measures of Statistical Serial Dependence: a Summary Statistic and an Extension of the Joint Interval Histogram

Description: Two measures which indicate statistical serial dependence were evaluated. The n-dimensional Average Stored Information index (ndASI) is a measure of conditional information, which compares the entropies of higher order conditional distributions to estimate average statistical serial dependence. The generalized ranked joint interval histogram (RJIH-o) is a new nonparametric graphical analysis method. It extends the joint interval histogram by depicting longer interval sequences and can be interp… more
Date: August 1994
Creator: Weil, Jon C. (Jon Christopher)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Combat Reconsidered: A Statistical Analysis of Small-Unit Actions During the American Civil War

Description: Historians often emphasize the physical features of battleterrain, weaponry, troop formations, earthworks, etc.in assessments of Civil War combat. Most scholars agree that these external combat conditions strongly influenced battle performance. Other historians accentuate the ways in which the mental stresses of soldiering affected combat performance. These scholars tend to agree that fighting effectiveness was influenced by such non-physical combat conditions as unit cohesion, leadership, mora… more
Date: December 2001
Creator: Barloon, Mark C.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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The Dynamic Foundation of Fractal Operators.

Description: The fractal operators discussed in this dissertation are introduced in the form originally proposed in an earlier book of the candidate, which proves to be very convenient for physicists, due to its heuristic and intuitive nature. This dissertation proves that these fractal operators are the most convenient tools to address a number of problems in condensed matter, in accordance with the point of view of many other authors, and with the earlier book of the candidate. The microscopic foundation … more
Date: May 2003
Creator: Bologna, Mauro
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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A Computer Assisted Drill and Practice System for Introductory Statistics Instruction

Description: To supplement college introductory statistics instruction, an interactive drill system was developed and implemented on a Hewlett- Packard 2000 timesharing computer. Unlimited practice in basic procedures and algorithms was provided over 38 topics including Chi-square, correlational methods, and one-way analysis of variance. Validation of intermediate computational steps was provided, and more difficult or remedial problems sets were made available. Optional files recorded performance data. Fou… more
Date: May 1979
Creator: Ellis, Richard George
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Random Sampling

Description: The purpose of this study is to show the use of random sampling in solving certain mathematical problems. The origin of random numbers to be used in sampling is discussed and methods of sampling from known distributions are then given together with an indication that the sampling procedures are unbiased.
Date: January 1957
Creator: Booker, Aaron Hicks
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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An Investigation of the Effect of Violating the Assumption of Homogeneity of Regression Slopes in the Analysis of Covariance Model upon the F-Statistic

Description: The study seeks to determine the effect upon the F-statistic of violating the assumption of homogeneity of regression slopes in the one-way, fixed-effects analysis of covariance model. The study employs a Monte Carlo simulation technique to vary the degree of heterogeneity of regression slopes with varied sample sizes within experiments to determine the effect of such conditions. One hundred and eighty-three simulations were used.
Date: August 1972
Creator: McClaran, Virgil Rutledge
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Algorithmic Music Analysis: a Case Study of a Prelude From David Cope’s “From Darkness, Light”

Description: The use of algorithms in compositional practice has been in use for centuries. With the advent of computers, formalized procedures have become an important part of computer music. David Cope is an American composer that has pioneered systems that make use of artificial intelligence programming techniques. In this dissertation one of David Cope’s compositions that was generated with one of his processes is examined in detail. A general timeline of algorithmic compositional practice is outlined f… more
Date: May 2015
Creator: Krämer, Reiner
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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