Inference About Two Means

This section deals with test used to compare the means of samples taken from two different populations.

This is actually a special case of hypothesis testing, with the null hypothesis being that the populations means are the same for the two groups.

There are three subsections which correspond to the three different situations we have covered:

• Inference about two means from paired (dependent) samples
• Inference about two means from independent samples:
  • Inference about two means with known population standard deviations $\sigma_1$ and $\sigma_2$
  • Inference about two means with unknown population standard deviations
  • Inference about two proportions

Each section has a link to a spreadsheet that can be used to perform the required calculations, and a detailed description of how to use it.