Test of homogeneity of covariances (or homoscedasticity) among several groups has many applications in statistical analysis. In the context of incomplete data analysis, tests of homoscedasticity among groups of cases with identical missing data patterns have been proposed to test whether data are missing completely at random (MCAR). These tests of…

Studies have shown that differences between children with and without handwriting difficulties lie not only in the written product (static data) but also in dynamic data of handwriting process. Since writing system varies among countries and individuals, this study was conducted to determine the feasibility of using quantitative outcome measures…

The responses of 2813 individuals to the Personal Globe Inventory (Tracey, 2002) were examined with the goal of developing a shorter, yet valid version of the scale using item response theory to guide the process. A random sample of 1000 individuals was used to select the best items and then the remaining 1813 were used as a validation sample to…

Largely due to dissatisfaction with the standard null hypothesis significance testing procedure, researchers have begun to consider alternatives. For example, Killeen (2005a) has argued that researchers should calculate p[subscript rep] that is purported to indicate the probability that, if the experiment in question were replicated, the obtained…

Two multi-level studies were conducted to examine the effects of attitudes towards coworkers on daily well-being. Study 1 linked daily levels of coworker satisfaction to job satisfaction and life satisfaction and examined the extent to which job satisfaction mediated the relationship between coworker satisfaction and life satisfaction among 33…

Using a sample of post-retirement workers (N = 176), this study investigated the role of future time perspective (FTP) in psychological contracts. The study aimed to test: (i) whether future time perspective is related to employer psychological contract fulfillment and (ii) whether it moderates relations between psychological contract fulfillment…

Despite recent shifts in research emphasizing the value of carefully designed experiments, the number of studies of teacher professional development with rigorous designs has lagged behind its student outcome counterparts. We outline a framework for the design of group randomized trials (GRTs) with teachers' knowledge as the outcome and…

A variety of factors are associated with students' achievement in secondary school physics, including cohort size--the total number of students studying Physics in the school--and socioeconomic status. Earlier studies also showed boys achieving better in Physics, while more recent research has shown better results for girls. Statistical analysis…

Problem Statement: The Teacher's-Act defined for the state-school teachers of North Cyprus shows that teachers are not selected according to any specific standards. In North Cyprus, apart from the exam topics defined at the teacher's exam regulations, there is not any kind of identified standard for teachers. Training qualified teachers based upon…

Professional Learning Communities (PLCs) are being used as a form of teacher professional development in schools across the world. The concept has been present in the educational literature for over thirty years. While many educators are familiar with the term, some schools have not yet implemented PLCs. Hord (1997) determined that all true PLCs…

Increasing demands for design rigor and an emphasis on evidence-based practice on a national level indicated a need for further guidance related to successful implementation of randomized studies in education. Rigorous and meaningful experimental research and its conclusions help establish a valid theoretical and evidence base for educational…

This three article mixed methods dissertation is titled "Three Studies on the Leadership Behaviors of Academic Deans in Higher Education." Each article is based on a sample of 51 academic deans from a three state region in the Southeastern United States. In the first study, the results of the statistical analyses reinforce the gender…

A differential item functioning (DIF) simulation study was conducted to explore the type and level of impact that contamination had on type I error and power rates in DIF analyses when the suspect item favored the same or opposite group as the DIF items in the matching subtest. Type I error and power rates were displayed separately for the…

The purpose of the study was to examine standardized test scores of school districts in the state of Texas that have implemented CSCOPE, a popular curriculum management system, in an effort to determine what effect, if any, its implementation has had. The standardized test used in the state of the Texas is titled the Texas Assessment of Knowledge…

In this article, the authors address the practicalities of how data should be presented, summarized, and interpreted. There are no exact rules; indeed there are valid concerns that exact rules may be inappropriate and too prescriptive. New procedures evolve, and new methods may be needed to deal with new types of data, just as people know that new…