Differences in accuracy of absolute and comparative performance appraisal methods

The primary question of this experiment was whether absolute and comparative performance appraisal ratings differ in terms of four components of accuracy: differential elevation (DE), differential accuracy (DA), elevation (EL), and stereotype accuracy (SA). Because comparative performance appraisal methods often use global items (overall performance dimensions), whereas certain absolute performance appraisal methods utilize specific items (critical incidents), the effect of specific versus global items was also investigated. Eighty participants viewed four videotaped lecturers and rated their performance 24 h later with both absolute and comparative performance appraisal methods which used both specific and global item-types. No advantages were associated with the absolute rating method, however, comparative ratings were more accurate than absolute ratings with respect to DA and SA. Global items resulted in greater DE and EL accuracy than did specific; however, the converse was true with respect to DA and SA accuracy. Implications for the practice of performance appraisal are discussed. (C) 1997 Academic Press.