ckkeep - Keep variables without losing validation
ckkeep varlist, [stubs(char stubs) listonly]
ckdrop varlist, [stubs(char stubs) listonly]
These functions replace keep and drop, when using attached characteristics for validation. Using these functions ensure that variables needed for validation or scoring of the kept variables are not mistakenly dropped.
INCLUDE help ckcharstub
listonly does not go through dropping any variables. It simply compiles a list of what variables would be left over if the command were actually run.
Online: help for keep, ckvar overview, ckchar
Bill Rising, StataCorp email: email@example.com web: http://homepage.mac.com/brising