Studied 52 nursing supervisors to examine the effects of a lecture on rating errors, discussion about errors, and participation in scale construction on both experimental and subsequent administrative ratings. On experimental ratings, scale construction reduced halo and variability errors, lecture reduced variability errors, and discussion increased variability errors. These results held true only for raters who began making ratings within 1 wk after training, before administration of questionnaires designed to measure rater motivation and knowledge. (27 ref) (PsycINFO Database Record (c) 2006 APA, all rights reserved). © 1979 American Psychological Association.