POWER-AND-EFFECT - A STATISTICAL UTILITY FOR MACINTOSH AND WINDOWS SYSTEMS

Significance tests are not the only step in statistics. Other consider ations include effect sizes and adequate sample sizes for a respectabl e level of statistical power. However, many statistical packages are s potty in their offerings of effect size, complex, and lack a friendly interface. Textbooks may have limited coverage, and calculations entai l several formulas and tables. Power & Effect offers a calculator- and formula-based metaphor to compute popular measures of effect size, si mple significance tests between effect sizes, combining of effect size s, simple significance tests based on known statistical values, and sa mple size determinations based on predicted result or effect size.