Statistics Calculator lets you use summary data to perform a wide variety of statistical significance tests. It's perfect for researchers who need to run a quick t-test to determine whether the difference between two percentages or two mean averages is statistically significant. Use it to calculate confidence intervals or to estimate the sample size for a study. Includes chi-square, t-tests, F-ratios, ANOVA, correlation, regression, Fisher's exact test, binomial test, poisson distribution, and others. On-line help contains extensive examples and explanations.