Sequential Task Performance: Task Module Relationships, Reliabilities, and Times

Abstract

A methodology has been developed and an experiment conducted to examine some of the assumptions and combinatorial rules employed in applying human performance reliability (HPR) and task time data to the quantification of human performance. Subjects performed a variety of tasks designed to provide empirical estimates of HPR and task time and to permit examination of the effects of combining tasks. Results indicated (a) the normality assumption for distribution of task time is inappropriate, (b) the rules for combining task times are satisfactory if the underlying distribution of task times in known, (c) HPR is affected severely by combining tasks, and (d) any model for estimating HPR will require parameters to account for task combining and difficulty.