Previous research has established that job performance changes over time, yet the implications of this dynamism for performance evaluations... Show morePrevious research has established that job performance changes over time, yet the implications of this dynamism for performance evaluations remain unclear. Studies that have examined the implications of different dynamic performance characteristics have mostly been laboratory based and have included a variety of performance measures, except for supervisor ratings of performance. Therefore, the present study integrates and builds on the literature on dynamic performance and performance ratings by examining its effects in an applied setting. Predictions were made about how the patterns in objective performance over a 12-month performance period would relate to annual performance appraisal ratings. Based on the monthly performance of 1,100 troopers working for a state law enforcement agency, main effects were found on supervisor ratings for the mean and trend in objective performance. However, the performance trend unexpectedly had a negative association with performance ratings. An interaction between the performance trend and variability also provided new information about how dynamic performance characteristics may interact to have an influence on ratings. Findings from the current study add to the existing research on dynamic performance characteristics and performance ratings, but more research is needed to understand the implications for different jobs and contexts. M.S. in in Psychology, December 2012 Show less