Teaching power analysis using regular statistical software

This paper presents a simple, unifying approach for teaching and computing power analysis for research designs involving linear and log-linear modeling. The principal advantage of this approach is that it borrows concepts, terminology, and software commonly used for data analysis within these systems. The scheme allows one to easily study the power of any test that can be performed with one's favorite linear or log-linear models routine, thereby making the method more flexible, precise, and "friendly" than table-based methods, such as those by Cohen (1977) and others.