In this lesson I start by setting up the workspace. Then I show you how to add a variable to a dataframe, how to create a nominal variable (a factor), and how to create a dataframe with scores for two separate groups. I also show you how to replace values in a variable. Then I go over how to get descriptive statistics (mean, standard deviation, variance), and how to calculate z scores. Finally, I show you how to add variables to your dataframe.