Some of the methods originally used to find relationships between reliability and power associated with a single measurement are extended to difference scores. Results, based on explicit power calculations, show that augmenting the reliability of measurement by reducing error score variance can make significance tests of difference more powerful.…

Two articles discuss the controversy about the relationship between reliability and the power of significance tests in response to the discussion of Donald W. Zimmerman, Richard H. Williams, and Bruno D. Zumbo. Lloyd G. Humphreys emphasizes the differences between what statisticians can do and constraints on researchers. Zimmerman, Williams, and…

Comments on discussions of statistical significance testing in this special issue, placing the articles in the context of contemporary research literature. Empirical evidence is cited that suggests that the American Psychological Association's policy of encouraging effect size reporting has had no appreciable effect on the research literature.…

Studied the attitudes of representatives of journals in education, sociology, and psychology through an electronic survey completed by 194 journal representatives. Results suggest that the majority of journals do not have written policies concerning the reporting of results from statistical significance testing, and most indicated that statistical…

In this study, we investigated possible context effects when students chose to defer items and answer those items later during a computerized test. In 4 primary school reading tests, 126 items were studied. Logistic regression analyses identified 4 items across 4 grade levels as statistically significant. However, follow-up analyses indicated that…

The objective of this study was to evaluate nutrition knowledge, attitudes and practices in Bahrain. A cross-sectional survey was carried out in 1998. Highly statistically significant differences (p less than 0.0001) were observed between practitioners and students in relation to knowledge concerning recommended daily allowance. The results…

Since the mid-1960s, when illicit drug use burgeoned in the normal youth population, substance use by American young people has proven to be a rapidly changing phenomenon. Smoking, drinking, and illicit drug use are leading causes of morbidity and mortality, both during adolescence as well as later in life. How vigorously the nation responds to…

The number of online education courses available to those seeking higher education have been increasing exponentially, offering opportunities to students who would not otherwise have been able to do so, as well as offering options for those who may have been able to attend classes on campus, but would prefer to pursue their course of study at…

This exploratory research study examined the impact of using feedback from weekly multiple-choice tests on final exam scores and students' IDEA course ratings. The teacher researcher taught two sections (N=33; N=34) of a graduate-level, semester-long, online course in advanced human growth and development. Each section had identical course…

Course management systems (CMSs) have become a common resource for resident courses at colleges and universities. Researchers have analyzed which CMS features faculty members use most primarily by asking them which features are used. The study described builds on previous research by counting the number of CMS features a faculty member used and by…

This investigation was motivated by observations that when persons with dysarthria increase loudness their speech improves. Some studies have indicated that this improvement may be related to an increase of prosodic variation. Studies have reported an increase of fundamental frequency (F0) variation with increased loudness, but there has been no…

The purpose of this study was to explore individual differences in children's tense onset growth trajectories and to determine whether any within- or between-child predictors could account for these differences. Twenty-two children with expressive vocabulary abilities in the low-average to below-average range participated. Sixteen children were at…

This research explored the degree to which group sizes can differ before the robustness of analysis of variance (ANOVA) and analysis of covariance (ANCOVA) are jeopardized. Monte Carlo methodology was used, allowing for the experimental investigation of potential threats to robustness under conditions common to researchers in education. The…

Conventional statistical significance tests do not inform the researcher regarding the likelihood that results will replicate. One strategy for evaluating result replication is to use a "bootstrap" resampling of a study's data so that the stability of results across numerous configurations of the subjects can be explored. This paper…

This paper summarizes an experiment conducted to examine the counting performance of 7- and 8-year-olds. Analysis of variance was computed on counting errors produced when enumerating a set of squares on a computer screen. The factors included in the analysis were age, gender, array size, error type, proximity, and error form. The primary…