Does success breed success? A quasi-experiment on strategic momentum in dynamic contests

We investigate whether professional agents react to changes of incentives during dynamic contests as predicted by contest theory. Using a large data set of point by point ball tracking data from tennis matches over the period 2005-2009, we exploit the randomised variation in point results that occurs when balls bounce very close from the court’s line to estimate the causal effect of winning a point on the chance to win the next point. In line with predictions from contest theory, we find evidence of a substantial momentum effect for male players. We do not find any significant effect for female players, suggesting the possible existence of gender differences in how agents react to incentives in contests.