The present study aimed at clarifying the various shortcomings of the Cohen's criteria for the interpretation of the values of the practical significance indicators. The hypothetical data were used for two experimental and control groups and calculating the paired-samples t-test. To clarify the inadequacy of Cohen's criteria in interpreting…

A guide for professional counselors and counseling researchers for calculating and interpreting Percent Improvement as an indicator of clinical significance is provided. Strategies for reporting findings are described and illustrated. Guidelines for contextualizing discussions of clinical significance within the boundaries of psychometric evidence…

Recent research has proposed a criterion to evaluate the reportability of subscores. This criterion is a value-added ratio ("VAR"), where values greater than 1 suggest that the true subscore is better approximated by the observed subscore than by the total score. This research extends the existing literature by quantifying statistical…

Null hypothesis significance testing (NHST) has been the subject of debate for decades and alternative approaches to data analysis have been proposed. This article addresses this debate from the perspective of scientific inquiry and inference. Inference is an inverse problem and application of statistical methods cannot reveal whether effects…

The subject of the research is focused on questioning teachers' attitudes in reference to using ICT competencies in the classroom, considering the gender, years of service and education, while the problem of the research concerns the question: What are the teachers' attitudes in reference to using ICT competencies in the classroom? Regarding to…

In this paper, we report a case study that illustrates the importance in interpreting the results from statistical tests, and shows the difference between practical importance and statistical significance. This case study presents three sets of data concerning the performance of two brands of batteries. The data are easy to describe and…

With growing popularity of single subject design as a method to evaluate the efficacy of interventions, it is important to ensure that the analyses of these methods are rigorous and reliable. The purpose of this case study is to discuss the measures used to evaluate the efficacy of interventions in single subject design studies in the fields of…

Correlated predictors in regression models are a fact of life in applied social science research. The extent to which they are correlated will influence the estimates and statistics associated with the other variables they are modeled along with. These effects, for example, may include enhanced regression coefficients for the other variables--a…

The authors of the study "The Long-Term Impact of Teachers" claim that their study shows that increases in teacher value-added lead to significant and lasting increases in test scores and significant increases in income that will last throughout adulthood. Instead, I show that these claims are false because they are contradicted by the…

The proliferation of online simulation games across the globe in many different languages offers Computer Assisted Language Learning (CALL) researchers an opportunity to examine how language learning occurs in such virtual environments. While there has recently been an increase in the number of exploratory studies involving learning experiences of…

The present paper aims to review two motivations to conduct "what if" analyses using Excel and "R" to understand the statistical significance tests through the sample size context. "What if" analyses can be used to teach students what statistical significance tests really do and in applied research either prospectively to estimate what sample size…

The use of confidence intervals (CIs) as an addition or as an alternative to null hypothesis significance testing (NHST) has been promoted as a means to make researchers more aware of the uncertainty that is inherent in statistical inference. Little is known, however, about whether presenting results via CIs affects how readers judge the…

The Journal of Agricultural Education (JAE) requires authors to follow the guidelines stated in the Publication Manual of the American Psychological Association [APA] (2009) in preparing research manuscripts, and to utilize accepted research and statistical methods in conducting quantitative research studies. The APA recommends the reporting of…

Null hypothesis significance testing has dominated quantitative research in education and psychology. However, the statistical significance of a test as indicated by a p-value does not speak to the practical significance of the study. Thus, reporting effect size to supplement p-value is highly recommended by scholars, journal editors, and academic…

Considering the range of changes in the instruction and learning of statistics, several questions emerge regarding how those changes influence students' attitudes. Equally, other questions emerge to reflect that statistics is a fundamental course in the university academic programs because of its relevance to the professional development of the…