Economists have for a long time argued that performance-based bonuses raise performance. Indeed, many firms use bonuses tied to individual performance to motivate their employees. However, there has been heated debate among human resources professionals recently, and some firms have moved away...

We compare evaluations of employee performance by individuals and groups of supervisors, analyzing a formal model and running a laboratory experiment. The model predicts that multi-rater evaluations are more precise than single-rater evaluations if groups rationally aggregate their signals about...