The DO Loop
Statistical programming in SAS with an emphasis on SAS/IML programs
Longitudinal data are measurements for a set of subjects at multiple points in time. Also called "panel data" or "repeated measures data," this kind of data is common in clinical trials in which patients are tracked over time. Recently, a SAS programmer asked how to visualize missing values in a
This article shows how to compute properties of a discrete probability distribution from basic definitions. You can use the definitions to compute the mean, variance, and median of a discrete probability distribution when there is no simple formula for those quantities. This article is motivated by two computational questions about
Statistical programmers need to access numerical constants that help us to write robust and accurate programs. Specifically, it is necessary to know when it is safe to perform numerical operations such as raising a number to a power without exceeding the largest number that is representable in finite-precision arithmetic. This