APA Dictionary of Psychology

a graph, often used in meta-analyses, in which the authors or titles of the studies are listed along the left side, and the corresponding effect size for each is given on the right. The effect sizes for the individual studies are usually indicated by squares in which the size of the square is proportional to the size of the effect for a specific study. At the bottom, the overall effect size is given, usually in a diamond shape whose width indicates the outer points of a confidence interval for the overall effect across all of the studies listed.