A two-sample t-test compares significant or random differences between two samples. It is most useful for hypothesis testing, ...

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 ...

This web calculator conducts a z-test for the difference between two populations' proportions. The calculator includes an explanation of inputs and outputs. This web calculator conducts a z-test for ...