Gives textbook-like explanation with some real-life data to compute a t-test and determine if two population means are equal. Also has some links for case studies and a web-based program called Dataplot. There is a printer-friendly version on the main homepage (see source).

This applet illustrates many features of a two-factor analysis of variance. Allows the user to adjust the group size and group means. Gives output of ANOVA table and a Venn diagram showing how the sum of squares total is divided among SSA, SSB, SSAxB, and SSE. Contains instructions on how to use the applet and an exercise set.

A slideshow presentation with two good examples on using the Z-test for the difference between two means. Gives some good "plain language" interepretations of what "statistically significant difference" means.