Knowledge of the magnitude of effect(s) of an experimental study in science education should be of utmost concern to researchers in the field, but is often not reported. This document describes the concept of "explained variance" in analysis of variance designs and then explains how it can be calculated and reported. Reporting the magnitude of…

The current state of usage of regression models in analysis of variance (ANOVA) designs is empirically examined, and examples of several statistical errors made in usage are presented. The assumptions of the general linear model are that all predictors are known without error of measurement and are fixed with no replication or sample variation; in…

This paper focuses on the use of the variable race in educational research. Researchers are clearly considered to have the right to choose their variables. But, the use of race in a nonscholarly fashion is held to be professionally inadequate and often detrimental to black Americans. For years, researchers using race to make comparison s between…