The irrational hungry judge effect revisited: Simulations reveal that the magnitude of the effect is overestimated

Danziger, Levav and Avnaim-Pesso (2011) analyzed legal rulings of Israeli parole boards concerning the effect of serial order in which cases are presented within ruling sessions. They found that the probability of a favorable decision drops from about 65% to almost 0% from the first ruling to the last ruling within each session and that the rate of favorable rulings returns to 65% in a session following a food break. The authors argue that these findings provide support for extraneous factors influencing judicial decisions and cautiously speculate that the effect might be driven by mental depletion. A simulation shows that the observed influence of order can be alternatively explained by a statistical artifact resulting from favorable rulings taking longer than unfavorable ones. An effect of similar magnitude would be produced by a (hypothetical) rational judge who plans ahead minimally and ends a session instead of starting cases that he or she assumes will take longer directly before the break. One methodological detail further increased the magnitude of the artifact and generates it even without assuming any foresight concerning the upcoming case. Implications for this article are discussed and the increased application of simulations to identify nonobvious rational explanations is recommended.