Frequency distributions (univariate and joint) can be displayed in contingency tables, or cross-tabulations. In this video we show how tapply() can be used to create such tables, but we…
This video presents an extended example from Mod8Script.R that deals with some fictitious quiz score data. Here we introduce several new functions for computing summary statistics and the t.test()…
This video describes how SAS processes a data step. It is important to understand that SAS accesses one observation at a time and processes each observation in a temporary location called the program…