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Schroger, Erich; And Others – Educational and Psychological Measurement, 1993
Minkowski distances are used to indicate similarity of two vectors in an N-dimensional space. How to compute the probability function, the expectation, and the variance for Minkowski distances and the special cases City-block distance and Euclidean distance. Critical values for tests of significance are presented in tables. (SLD)
Descriptors: Equations (Mathematics), Probability, Statistical Distributions, Statistical Significance
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Gross, Alan L.; Torres-Quevedo, Rocio – Psychometrika, 1995
The posterior distribution of the bivariate correlation is analytically derived given a data set where "X" is completely observed, but "Y" is missing at random for a portion of the sample. Interval estimates of the correlation are constructed from the posterior distribution in terms of the highest density regions. (SLD)
Descriptors: Bayesian Statistics, Correlation, Equations (Mathematics), Estimation (Mathematics)
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Camilli, Gregory – Psychometrika, 1995
This paper demonstrates that two major tests for two-by-two tables, Fisher's exact and Pearson's chi-square tests, are highly related from a Bayesian perspective. A formal similarity is demonstrated in small samples, and reasons for the relationship are discussed. (SLD)
Descriptors: Bayesian Statistics, Chi Square, Equations (Mathematics), Probability
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Zeng, Lingjia; And Others – Applied Psychological Measurement, 1994
A general delta method is described for computing the standard error (SE) of a chain of linear equations. The general delta method derives the SEs directly from the moments of the score distributions obtained in the equating chain. Computer simulations demonstrate the method. (SLD)
Descriptors: Computer Simulation, Equated Scores, Error of Measurement, Statistical Distributions
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Rousseau, Ronald – Journal of the American Society for Information Science, 1992
Proposes a mathematical model to explain the observed concentration or diversity of nominal classes in information retrieval systems. The Lorenz Curve is discussed, Information Production Process (IPP) is explained, and a heuristic explanation of circumstances in which the model might be used is offered. (30 references) (LRW)
Descriptors: Heuristics, Information Retrieval, Mathematical Models, Research Needs
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Soltysik, Robert C.; Yarnold, Paul R. – Educational and Psychological Measurement, 1994
This article describes the theoretical distribution of optima arising from two-category univariable optimal discriminant analysis (UniODA) of continuous random data for a one-tailed (directional) hypothesis. Directional UniODA is illustrated through an investigation of the relationship between depression and brain monoamine turnover. (SLD)
Descriptors: Depression (Psychology), Discriminant Analysis, Neuropsychology, Research Methodology
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Kamakura, Wagner A. – Psychometrika, 1991
Two ideal-point probabilistic choice models from the external analysis of preferences are presented that allow for more flexible distributions of ideal-points. The first extends the probit model of W. Kamakura and R. Srivastava. The second is based on simplifying assumptions that lead to a multidimensional histogram of ideal-points. (SLD)
Descriptors: Equations (Mathematics), Estimation (Mathematics), Graphs, Mathematical Models
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Zimmerman, Donald W. – Journal of Experimental Education, 1992
The power functions of Student t tests performed on initial scores, ordinary ranks, 3 kinds of modular ranks, and dichotomies were investigated for 1 normal and 3 nonnormal distributions using 2 samples of 26 simulated scores each. Advantages of extending the rank transformation concept are discussed. (SLD)
Descriptors: Computer Simulation, Nonparametric Statistics, Power (Statistics), Scores
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Bang, Jung W.; Schumacker, Randall E.; Schlieve, Paul L. – Educational and Psychological Measurement, 1998
The normality of number distributions generated by various random-number generators were studied, focusing on when the random-number generator reached a normal distribution and at what sample size. Findings suggest the steps that should be followed when using a random-number generator in a Monte Carlo simulation. (SLD)
Descriptors: Monte Carlo Methods, Sample Size, Simulation, Statistical Distributions
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Zimmerman, Donald W. – Journal of Experimental Education, 1995
It is argued that outlier-prone distributions reduce the power of nonparametric tests, but power can be restored through procedures usually associated with parametric tests. Computer simulation is used to show how an outlier detection and downweighting procedure augments the power of the t-test and the Wilcoxon-Mann-Whitney test. (SLD)
Descriptors: Computer Simulation, Identification, Nonparametric Statistics, Power (Statistics)
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Zeng, Lingjia – Applied Psychological Measurement, 1997
Proposes a marginal Bayesian estimation procedure to improve item parameter estimates for the three parameter logistic model. Computer simulation suggests that implementing the marginal Bayesian estimation algorithm with four-parameter beta prior distributions and then updating the priors with empirical means of updated intermediate estimates can…
Descriptors: Algorithms, Bayesian Statistics, Estimation (Mathematics), Statistical Distributions
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Hayes, Kevin – Teaching Statistics: An International Journal for Teachers, 2004
This article demonstrates that the lower bound for the most deviant Z score and the upper bound for the sample standard deviation are attained simultaneously.
Descriptors: Statistical Analysis, Scores, Item Response Theory, Probability
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Rodriguez-Lopez, Margarita; Carrasquillo, Arnaldo, Jr. – Journal of Chemical Education, 2006
This article describes the central limit theorem (CLT) and its relation to analytical chemistry. The pedagogic rational, which argues for teaching the CLT in the analytical chemistry classroom, is discussed. Some analytical chemistry concepts that could be improved through an understanding of the CLT are also described. (Contains 2 figures.)
Descriptors: Chemistry, Misconceptions, Statistical Distributions, Science Instruction
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Thompson, Bruce – 1996
Multivariate normality is required for some statistical tests. This paper explores the implications of violating the assumption of multivariate normality and illustrates a graphical procedure for evaluating multivariate normality. The logic for using the multivariate bootstrap is presented. The multivariate bootstrap can be used when distribution…
Descriptors: Computer Assisted Testing, Computer Software, Correlation, Statistical Distributions
Lewis, Charla P. – 1999
The sampling distribution is a common source of misuse and misunderstanding in the study of statistics. The sampling distribution, underlying distribution, and the Central Limit Theorem are all interconnected in defining and explaining the proper use of the sampling distribution of various statistics. The sampling distribution of a statistic is…
Descriptors: Estimation (Mathematics), Probability, Sample Size, Sampling
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