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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
Partner: UNT Libraries
open access

A Comparison of Two Criterion-Referenced Item-Selection Techniques Utilizing Simulated Data with Item Pools that Vary in Degrees of Item Difficulty

Description: The problem of this study was to examine the equivalency of two different types of criterion-referenced item-selection techniques on simulated data as item pools varied in degrees of item difficulty. A pretest-posttest design was employed in which pass-fail scores were randomly generated for item pools of twenty-five items. From the item pools, the two techniques determined which items were to be used to make up twelve-item criterion-referenced tests. The twenty-five items also were rank ordere… more
Date: May 1974
Creator: Davis, Robbie G.
Partner: UNT Libraries
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Factors Influencing Difficult Special Education Referral Recommendations

Description: The present study is concerned with selected factors that may strongly influence classroom teachers to refer young children for possible placement in special classes when the children are functioning near the borderline for placement on the basis of intelligence test scores. Particular attention was given to the contribution of student attributes (i.e., sex, ethnic background, socioeconomic status, and classroom behavior) and teacher attributes (i.e., age, sex, ethnic background and teaching ex… more
Date: August 1975
Creator: Luckey, Robert E.
Partner: UNT Libraries
open access

An Empirical Investigation of Tukey's Honestly Significant Difference Test with Variance Heterogeneity and Unequal Sample Sizes, Utilizing Kramer's Procedure and the Harmonic Mean

Description: This study sought to determine the effect upon Tukey's Honestly Significant Difference (HSD) statistic of concurrently violating the assumptions of homogeneity of variance and equal sample sizes. Two forms for the unequal sample size problem were investigated. Kramer's form and the harmonic mean approach were the two unequal sample size procedures studied. The study employed a Monte Carlo simulation procedure which varied sample sizes with a heterogeneity of variance condition. Four thousand ex… more
Date: May 1976
Creator: McKinney, William Lane
Partner: UNT Libraries
open access

An Empirical Investigation of Marascuilo's Ú₀ Test with Unequal Sample Sizes and Small Samples

Description: The study seeks to determine the effect upon the Marascuilo Ú₀ statistic of violating the small sample assumption. The study employed a Monte Carlo simulation technique to vary the degree of sample size and unequal sample sizes within experiments to determine the effect of such conditions, Twenty-two simulations, with 1200 trials each, were used. The following conclusion appeared to be appropriate: The Marascuilo Ú₀ statistic should not be used with small sample sizes and it is recommended that… more
Date: August 1976
Creator: Milligan, Kenneth W.
Partner: UNT Libraries
open access

Boundary Conditions of Several Variables Relative to the Robustness of Analysis of Variance Under Violation of the Assumption of Homogeneity of Variances

Description: The purpose of this study is to determine boundary conditions associated with the number of treatment groups (K), the common treatment group sample size (n), and an index of the extent to which the assumption of equality of treatment population variances is violated (Q) with regard to user confidence in application of the one-way analysis of variance F-test for determining equality of treatment population means. The study concludes that the analysis of variance F-test is robust when the number … more
Date: December 1977
Creator: Grizzle, Grady M.
Partner: UNT Libraries
open access

Cross Categorical Scoring: An Approach to Treating Sociometric Data

Description: The purpose of this study was to use a cross categorical scoring method for sociometric data focusing upon those individuals who have made the selections. A cross category selection was defined as choosing an individual on a sociometric instrument who was not within one's own classification. The classifications used for this study were sex, race, and perceived achievement level. A cross category score was obtained by summing the number of cross category selections. The conclusions below are the… more
Date: December 1977
Creator: Ernst, Nora Wilford
Partner: UNT Libraries
open access

Principles for Formulating and Evaluating Instructional Claims

Description: The problem with which this investigation is concerned is that of developing (a) the concept of instructional claim, and (b) credible principles for instructional claim formulation and evaluation. The belief that these constructions are capable of contributing to the advancement of curricular and instructional research and practice is grounded in three major features. The first feature is that of increased precision of basic concepts and increased coherence among them. The second feature is the… more
Date: August 1978
Creator: McCray, Emajean
Partner: UNT Libraries
open access

An Empirical Investigation of Tukey's Honestly Significant Difference Test with Variance Heterogeneity and Equal Sample Sizes, Utilizing Box's Coefficient of Variance Variation

Description: This study sought to determine boundary conditions for robustness of the Tukey HSD statistic when the assumptions of homogeneity of variance were violated. Box's coefficient of variance variation, C^2 , was utilized to index the degree of variance heterogeneity. A Monte Carlo computer simulation technique was employed to generate data under controlled violation of the homogeneity of variance assumption. For each sample size and number of treatment groups condition, an analysis of variance F-tes… more
Date: May 1980
Creator: Strozeski, Michael W.
Partner: UNT Libraries
open access

An Application of Ridge Regression to Educational Research

Description: Behavioral data are frequently plagued with highly intercorrelated variables. Collinearity is an indication of insufficient information in the model or in the data. It, therefore, contributes to the unreliability of the estimated coefficients. One result of collinearity is that regression weights derived in one sample may lead to poor prediction in another model. One technique which was developed to deal with highly intercorrelated independent variables is ridge regression. It was first propose… more
Date: December 1980
Creator: Amos, Nancy Notley
Partner: UNT Libraries
open access

The Effects of the Ratio of Utilized Predictors to Original Predictors on the Shrinkage of Multiple Correlation Coefficients

Description: This study dealt with shrinkage in multiple correlation coefficients computed for sample data when these coefficients are compared to the multiple correlation coefficients for populations and the effect of the ratio of utilized predictors to original predictors on the shrinkage in R square. The study sought to provide the rationale for selection of the shrinkage formula when the correlations between the predictors and the criterion are known and determine which of the three shrinkage formulas (… more
Date: August 1983
Creator: Petcharat, Prataung Parn
Partner: UNT Libraries
open access

Short-to-Medium Term Enrollment Projection Based on Cycle Regression Analysis

Description: Short-to-medium projections were made of student semester credit hour enrollments for North Texas State University and the Texas Public and Senior Colleges and Universities (as defined by the Coordinating Board, Texas College and University System). Undergraduate, Graduate, Doctorate, Total, Education, Liberal Arts, and Business enrollments were projected. Fall + Spring, Fall, Summer I + Summer II, Summer I were time periods for which projections were made. A new regression analysis called "cyc… more
Date: August 1983
Creator: Chizari, Mohammad
Partner: UNT Libraries
open access

Willingness of Educators to Participate in a Descriptive Research Study as a Function of a Monetary Incentive

Description: The problem considered involved assessing willingness of educators to participate in a study offering monetary incentives. Determination of willingness was implemented by sending educators a packet requesting return of a postcard to indicate willingness to participate. The purpose was twofold: to determine the effect of a monetary incentive upon willingness of educators to participate in a research study, and to analyze implications for mail questionnaire studies. A sample of 600 educators was … more
Date: May 1984
Creator: Pittman, Doyle
Partner: UNT Libraries
open access

A Monte Carlo Study of the Robustness and Power of Analysis of Covariance Using Rank Transformation to Violation of Normality with Restricted Score Ranges for Selected Group Sizes

Description: The study seeks to determine the robustness and power of parametric analysis of covariance and analysis of covariance using rank transformation to violation of the assumption of normality. The study employs a Monte Carlo simulation procedure with varying conditions of population distribution, group size, equality of group size, scale length, regression slope, and Y-intercept. The procedure was performed on raw data and ranked data with untied ranks and tied ranks.
Date: December 1984
Creator: Wongla, Ruangdet
Partner: UNT Libraries
open access

A Comparison of Three Methods of Detecting Test Item Bias

Description: This study compared three methods of detecting test item bias, the chi-square approach, the transformed item difficulties approach, and the Linn-Harnish three-parameter item response approach which is the only Item Response Theory (IRT) method that can be utilized with minority samples relatively small in size. The items on two tests which measured writing and reading skills were examined for evidence of sex and ethnic bias. Eight sets of samples, four from each test, were randomly selected fro… more
Date: May 1985
Creator: Monaco, Linda Gokey
Partner: UNT Libraries
open access

The Robustness of O'Brien's r Transformation to Non-Normality

Description: A Monte Carlo simulation technique was employed in this study to determine if the r transformation, a test of homogeneity of variance, affords adequate protection against Type I error over a range of equal sample sizes and number of groups when samples are obtained from normal and non-normal distributions. Additionally, this study sought to determine if the r transformation is more robust than Bartlett's chi-square to deviations from normality. Four populations were generated representing norma… more
Date: August 1985
Creator: Gordon, Carol J. (Carol Jean)
Partner: UNT Libraries
open access

A Monte Carlo Analysis of Experimentwise and Comparisonwise Type I Error Rate of Six Specified Multiple Comparison Procedures When Applied to Small k's and Equal and Unequal Sample Sizes

Description: The problem of this study was to determine the differences in experimentwise and comparisonwise Type I error rate among six multiple comparison procedures when applied to twenty-eight combinations of normally distributed data. These were the Least Significant Difference, the Fisher-protected Least Significant Difference, the Student Newman-Keuls Test, the Duncan Multiple Range Test, the Tukey Honestly Significant Difference, and the Scheffe Significant Difference. The Spjøtvoll-Stoline and Tuke… more
Date: December 1985
Creator: Yount, William R.
Partner: UNT Libraries
open access

A Comparison of Some Continuity Corrections for the Chi-Squared Test in 3 x 3, 3 x 4, and 3 x 5 Tables

Description: This study was designed to determine whether chis-quared based tests for independence give reliable estimates (as compared to the exact values provided by Fisher's exact probabilities test) of the probability of a relationship between the variables in 3 X 3, 3 X 4 , and 3 X 5 contingency tables when the sample size is 10, 20, or 30. In addition to the classical (uncorrected) chi-squared test, four methods for continuity correction were compared to Fisher's exact probabilities test. The four met… more
Date: May 1987
Creator: Mullen, Jerry D. (Jerry Davis)
Partner: UNT Libraries
open access

A comparison of the Effects of Different Sizes of Ceiling Rules on the Estimates of Reliability of a Mathematics Achievement Test

Description: This study compared the estimates of reliability made using one, two, three, four, five, and unlimited consecutive failures as ceiling rules in scoring a mathematics achievement test which is part of the Iowa Tests of Basic Skill (ITBS), Form 8. There were 700 students randomly selected from a population (N=2640) of students enrolled in the eight grades in a large urban school district in the southwestern United States. These 700 students were randomly divided into seven subgroups so that each … more
Date: May 1987
Creator: Somboon Suriyawongse
Partner: UNT Libraries
open access

Effect of Rater Training and Scale Type on Leniency and Halo Error in Student Ratings of Faculty

Description: The purpose of this study was to determine if leniency and halo error in student ratings could be reduced by training the student raters and by using a Behaviorally Anchored Rating Scale (BARS) rather than a Likert scale. Two hypotheses were proposed. First, the ratings collected from the trained raters would contain less halo and leniency error than those collected from the untrained raters. Second, within the group of trained raters the BARS would contain less halo and leniency error than the… more
Date: May 1987
Creator: Cook, Stuart S. (Stuart Sheldon)
Partner: UNT Libraries
open access

Comparison of Methods for Computation and Cumulation of Effect Sizes in Meta-Analysis

Description: This study examined the statistical consequences of employing various methods of computing and cumulating effect sizes in meta-analysis. Six methods of computing effect size, and three techniques for combining study outcomes, were compared. Effect size metrics were calculated with one-group and pooled standardizing denominators, corrected for bias and for unreliability of measurement, and weighted by sample size and by sample variance. Cumulating techniques employed as units of analysis the eff… more
Date: December 1987
Creator: Ronco, Sharron L. (Sharron Lee)
Partner: UNT Libraries
open access

The Characteristics and Properties of the Threshold and Squared-Error Criterion-Referenced Agreement Indices

Description: Educators who use criterion-referenced measurement to ascertain the current level of performance of an examinee in order that the examinee may be classified as either a master or a nonmaster need to know the accuracy and consistency of their decisions regarding assignment of mastery states. This study examined the sampling distribution characteristics of two reliability indices that use the squared-error agreement function: Livingston's k^2(X,Tx) and Brennan and Kane's M(C). The sampling distri… more
Date: May 1988
Creator: Dutschke, Cynthia F. (Cynthia Fleming)
Partner: UNT Libraries
open access

A Comparison of Three Item Selection Methods in Criterion-Referenced Tests

Description: This study compared three methods of selecting the best discriminating test items and the resultant test reliability of mastery/nonmastery classifications. These three methods were (a) the agreement approach, (b) the phi coefficient approach, and (c) the random selection approach. Test responses from 1,836 students on a 50-item physical science test were used, from which 90 distinct data sets were generated for analysis. These 90 data sets contained 10 replications of the combination of three d… more
Date: August 1988
Creator: Lin, Hui-Fen
Partner: UNT Libraries
open access

The Analysis of the Accumulation of Type II Error in Multiple Comparisons for Specified Levels of Power to Violation of Normality with the Dunn-Bonferroni Procedure: a Monte Carlo Study

Description: The study seeks to determine the degree of accumulation of Type II error rates, while violating the assumptions of normality, for different specified levels of power among sample means. The study employs a Monte Carlo simulation procedure with three different specified levels of power, methodologies, and population distributions. On the basis of the comparisons of actual and observed error rates, the following conclusions appear to be appropriate. 1. Under the strict criteria for evaluation of … more
Date: August 1989
Creator: Powers-Prather, Bonnie Ann
Partner: UNT Libraries
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