The Validity of Task Coverage Ratings by Incumbents and Supervisors: Bad News

In this study incumbents from three different jobs were asked to rate lists of their job tasks on various constructs (e.g., time, importance) and then estimate the percentage of their job tasks (task coverage) included in the task list. Incumbents made these ratings under one of two conditions. In two instances, two months after making an initial task coverage rating for the entire list of tasks, the same incumbents were asked to estimate the task coverage of a reduced list of tasks (i.e., half to two-thirds of the tasks were removed from the list presented for rating). In a third instance one group of incumbents completed an entire inventory while a second group completed a reduced inventory. The average task coverage rating for the entire inventories were high (percent estimates ranging in the 80's–90's) and the average of the reduced inventories was much higher than expected (percent estimates in the 70's). It was concluded that incumbents and supervisors were not able to accurately estimate task coverage.