Using a linear model to compare the mean of two groups

The t-test is a statistical method used to help us decide whether there is likely to be a difference between the means of two groups. t-tests are probably the most widely used tests in bioinformatics and biology, usually applied without consideration as to whether the assumptions of the test hold and can be intepreted without criticism. By learning how to do the t-test through building a linear model, you will be able to test whether the assumptions hold since a well fit model implies a good fit to the assumptions. The t-test is a special case of the linear model because it can be framed as a linear regression problem with a binary predictor variable.

In the linear model, we try to fit a linear equation that describes the relationship between a response output variable (dependent variable) and one or more predictor input variables (independent variables). In the case of a t-test, we have one binary predictor variable, which...