MINSIZE2: A computer program for determining effect size and minimum sample size for statistical significance for univariate, multivariate, and nonparametric tests

The American Psychological Association's editorial style urges authors to p rovide effect size estimates. Several journals, including Educational and P sychological Measurement, have adopted author guidelines that call for dete rmining the minimum sample size necessary for a given result to have been d eclared statistically significant. MINSIZE2, a computer program that permit s the user to determine both effect size and the minimum sample size needed for the results of a given analysis to be statistically significant, is de scribed. Program applications for statistical significance tests for univar iate, multivariate, and nonparametric statistics are provided. Explanation of the program's operation is given, and examples are furnished.