Most psychology journals now require authors to report a sample value of effect size along with hypothesis testing results. The sample effect size value can be misleading because it contains sampling error. Authors often incorrectly interpret the sample effect size as if it were the population effect size. A simple solution to this problem is to…

Standard least squares analysis of variance methods suffer from poor power under arbitrarily small departures from normality and fail to control the probability of a Type I error when standard assumptions are violated. This article describes a framework for robust estimation and testing that uses trimmed means with an approximate degrees of…

One version of r-sub(equivalent), calculated from Fisher's exact test p values and recommended for small samples, is considered "a more realistic... [and] a more accurate estimate of the population correlation than... the sample correlation, r-sub(sample)" (R. Rosenthal & D. B. Rubin, 2003, p. 494). Small sample properties of r-sub(sample) and of…