Performance and Seniority

An accepted axiom, and one that seems quite reasonable, is that the longer you hold a job the more proficient you become at performing that job. This study investigated the relationship between seniority and job performance. Two different studies are reported. In Study 1, the sample consisted of both entry-level police and firefighters and first-level supervisors. These incumbents and supervisors were asked to rate the percentage of incumbents with a given number of years on the job, ranging from 1 to 7, who would be able to competently perform the first-level supervisory job. Both samples (police and fire) demonstrated a trend of increasing levels of expected performance through the first 5 years on the job. Beyond the 5-year point, the relationship between the variables no longer demonstrated a simple linear effect. Study 2 investigated the use of seniority in a concurrent validation design. More specifically, the study looked at the unique contribution of seniority to the prediction of job performance after controlling for age and two selection test scores. The results demonstrated that seniority had a nonsignificant linear contribution across the entire range of seniority values. However, when the sample was divided into two groups consisting of 2-5 years and more than 5 years of seniority, seniority did have a significant linear contribution for the 2-5 year sample. The use of seniority in selection and the resulting implications for adverse impact are discussed.