A t-test for population means compares the means between two populations. It is appropriate when the population standard deviations are unknown. This applet allows users to change the distributions of ...

Like the Wilcoxon test, the t-test is used to determine if there is a meaningful difference between two related samples. T-tests are used when there is a normal distribution and the data variances are ...

In the Two-Sample Test for Proportions task, you can determine whether two probabilities are the same. The data analyzed in this example are taken from a study measuring the accuracy of two computer ...