Upstairs and Downstairs: The Imperfections of Cricket's Decision Review System

Under cricket's decision review system (DRS) a player may request a review of dismissal decisions taken by on-field umpires. Reviews of leg before wicket decisions, the focus of this article, occur through a ball-tracking technology popularly called Hawk-Eye. If Hawk-Eye makes mistakes, in the face of such errors, the overall error rate can be decomposed into a technology error rate and a human error rate. Consequently, improved decision can be achieved through better technology or better umpires. We argue that, given the costs of DRS, the same gains could be obtained, at lower cost, by investing in umpires rather than technology.