Testing Hypotheses - Differences Between Two Means

You have three options in the Data Analysis Toolpak for a t test in Excel. Read below if you aren’t sure which test to choose or skip to the section you need:

Paired Two Sample for means in Excel.
Two Sample T test in Excel assuming Equal Variances.
Two-sample T test in Excel assuming Unequal variances.

A two sample z test in Excel compares the means of two sets of data to see if there’s a difference. You run a z test to test the null hypothesis. You use the p value from the test to decide whether to support or reject the null hypothesis. For example, you might be asked by a manufacturer to test if some new product is superior to a previous product in shelf life. You would start by stating the null hypothesis (there’s no difference) and then state your alternate hypothesis: there IS a difference in means. Once you’ve figured out your null and alternate hypotheses, you’re ready to run the z test in Excel.