This research examined whether differences among job incumbents in the
ir task ratings could be attributed to systematic as well as random va
riation. Data collected from 83 respondents showed that there was a si
gnificant degree of interrater agreement regarding task importance but
not for ratings of task time spent. Moreover, measures of job context
were significantly correlated with ratings of time spent but not task
importance. These results suggest that within-job variation among rat
ers can have both systematic and random components. Thus, practitioner
s should collect data on the job context as well as on incumbents' dem
ographic characteristics and experience. Personnel practices based on
task analyses may need to be examined to ensure that they are compatib
le with local variation in the job.