//  include:    wf7-include-sample.doi
//  used by:    wf7-include-sample.do \ for stata 9
//  task:       define sample for tenure example
//  project:    workflow chapter 7
//  author:     scott long \ 2008-10-24

//  #1
//  load data and select sample

use wf-tenure, clear
* in stata 10 and later: datasignature confirm
drop if year>=11 // drop cases with long time in rank
drop if prestige<1 // drop if unrated department