Speaking Stata: More ways for rowwise

A previous column (Cox, 2009, Stata Journal 9: 137{157) gave a review of methods for working rowwise in Stata. Here rows means observations in a dataset, and the concern is calculations in each observation with a bundle of variables. For example, a row mean variable can be generated as the mean of some numeric variables in each observation. This column is an update. It is briefly flagged that official Stata now has rowmedian() and rowpctile() functions for egen. The main focus is on returning which variable or variables are equal to the maximum or minimum in a row. The twist that requires care is that two or more variables can tie for minimum or maximum. That may entail a decision on what is to be recorded, such as all of them or just the first or last occurrence of an extreme.