Free Tool: G*Power 3

Title: Free Tool: G*Power 3 Category: tools (free, no-cost) / statistical software / English language Clicks: 276 Listing added: Jun 12, 2007

G*Power 3 covers statistical power analyses for many different statistical tests of the
* F test,
* t test,
* χ2-test and
* z test families and some
* exact tests.
G*Power 3 offers five different types of statistical power analysis:
* A priori (sample size N is computed as a function of power level 1-β, significance level α, and the to-be-detected population effect size)
* Compromise (both α and 1-β are computed as functions of effect size, N, and an error probability ratio q = β/α)
* Criterion (α and the associated decision criterion are computed as a function of 1-β, the effect size, and N)
* Post-hoc (1-β is computed as a function of α, the population effect size, and N)
* Sensitivity (population effect size is computed as a function of α, 1-β, and N)
G*Power 3 provides improved effect size calculators and graphics options. It supports both a distribution-based and a design-based input mode.
G*Power 3 is available for Mac OS X 10.4 and Windows XP/Vista.
G*Power 3 is free.