The purpose of this study was to examine the potential of three independent psychological scales (Rotter's Locus of Control, Karasek's Job Content Questionnaire [non-injury job stress], and Rosenberg's Self-Esteem Scale) to predict job satisfaction, as measured by Brayfield and Rothe's Index of Job Satisfaction, among salespersons in a small independent department store in Wichita Falls, Texas. An 82-item survey which examined the dynamics of a salesperson's work life was administered to 20 individuals who were full-time employees of the department store. Demographic data were also gathered although these factors were not entered into the regression analysis. A multiple regression procedure examined the responses of the 20 employees who participated in the study. The R-squared coefficient indicates that 41 percent of the variance in Job Satisfaction was explained by the three predictor measures. A major proportion of this unexplained variance may be in variables outside the scope of this study, e.g., salaries, vacation time, benefits, bonuses, or commissions. Results suggest that the independent variables measured by the Locus of Control Scale and the Job Content Questionnaire in combination were the best predictors of job satisfaction with a significance level of .01. The single best predictor was the Job Content Questionnaire, significant …

A Monte Carlo simulation study investigated the effect of scoring format, item parameterization, threshold configuration, and prior ability distribution on the accuracy of ability estimation given various IRT models. Item response data on 30 items from 1,000 examinees was simulated using known item parameters and ability estimates. The item response data sets were submitted to seven dichotomous or polytomous IRT models with different item parameterization to estimate examinee ability. The accuracy of the ability estimation for a given IRT model was assessed by the recovery rate and the root mean square errors. The results indicated that polytomous models produced more accurate ability estimates than the dichotomous models, under all combinations of research conditions, as indicated by higher recovery rates and lower root mean square errors. For the item parameterization models, the one-parameter model out-performed the two-parameter and three-parameter models under all research conditions. Among the polytomous models, the partial credit model had more accurate ability estimation than the other three polytomous models. The nominal categories model performed better than the general partial credit model and the multiple-choice model with the multiple-choice model the least accurate. The results further indicated that certain prior ability distributions had an effect on the accuracy …

There is currently no effective tool available to quickly and economically measure a change in landmass in the setting of biomedical professionals and environmental specialists. The purpose of this study is to structure and demonstrate a statistical change-detection method using remotely sensed data that can detect the presence of an infectious land borne disease. Data sources included the Texas Department of Health database, which provided the types of infectious land borne diseases and indicated the geographical area to study. Methods of data collection included the gathering of images produced by digital orthophoto quadrangle and aerial videography and Landsat. Also, a method was developed to identify statistically the severity of changes of the landmass over a three-year period. Data analysis included using a unique statistical detection procedure to measure the severity of change in landmass when a disease was not present and when the disease was present. The statistical detection method was applied to two different remotely sensed platform types and again to two like remotely sensed platform types. The results indicated that when the statistical change detection method was used for two different types of remote sensing mediums (i.e.-digital orthophoto quadrangle and aerial videography), the results were negative due to …

How to identify effective teachers who improve student achievement despite diverse student populations and school contexts is an ongoing discussion in public education. The need to show communities and parents how well teachers and schools improve student learning has led districts and states to seek a fair, equitable and valid measure of student growth using student achievement. This study investigated a two stage hierarchical model for estimating teacher effect on student achievement. This measure was entitled a Classroom Effectiveness Index (CEI). Consistency of this model over time, outlier influences in individual CEIs, variance among CEIs across four years, and correlations of second stage student residuals with first stage student residuals were analyzed. The statistical analysis used four years of student residual data from a state-mandated mathematics assessment (n=7086) and a state-mandated reading assessment (n=7572) aggregated by teacher. The study identified the following results. Four years of district grand slopes and grand intercepts were analyzed to show consistent results over time. Repeated measures analyses of grand slopes and intercepts in mathematics were statistically significant at the .01 level. Repeated measures analyses of grand slopes and intercepts in reading were not statistically significant. The analyses indicated consistent results over time for reading …

The purpose of this study was to determine whether varying levels of computer anxiety have an effect on computer-based testing of United States Air Force technical training students. The first chapter presents an overview of computer-based testing, defines key terms, and identifies questions addressed in the research. The rationale for conducting this study was that little research had been done in this area. The second chapter contains a review of the pertinent literature related to computer-based testing, computer anxiety, test reliability, validity, and gender differences in computer use. Due to the lack understanding concerning any effects of computer anxiety on computer-based testing, this has been a worthwhile topic to explore, and it makes a significant contribution to the training field. The third chapter describes the qualitative research methodology used to conduct the study. The primary methodology was an analysis of variance comparison for groups of individuals who displayed high or low computer anxiety to their respective mean computer-based or paper-based aircraft maintenance knowledge testing scores. The research population consisted of United States Air Force aircraft maintenance craftsmen students attending training at Sheppard Air Force Base, Texas. The fourth chapter details the findings of the study. The findings indicate that there …