Another recent (slightly amusing but) good one from Psychological Science. (Related here and here).
Temper, Temperature, and Temptation
Heat-Related Retaliation in Baseball
Richard P. Larrick, Thomas A. Timmerman, Andrew M. Carton and Jason Abrevaya
Abstract: In this study, we analyzed data from 57,293 Major League Baseball games to test whether high temperatures interact with provocation to increase the likelihood that batters will be hit by a pitch. Controlling for a number of other variables, we conducted analyses showing that the probability of a pitcher hitting a batter increases sharply at high temperatures when more of the pitcher’s teammates have been hit by the opposing team earlier in the game. We suggest that high temperatures increase retaliation by increasing hostile attributions when teammates are hit by a pitch and by lowering inhibitions against retaliation.