Does Success Breed Success? a Quasi-Experiment on Strategic Momentum in Dynamic Contests

We study how agents adapt their behaviour to variations of incentives in dynamic contests. We investigate a real dynamic contest with large stakes: professional tennis matches. Situations in which balls bounce very close to the court’s lines are used as the setting of a quasi-experiment providing random variations in winning probability. We find evidence of a momentum effect for men whereby winning a point has a positive causal impact on the probability to win the next one. This behaviour is compatible with a reaction to the asymmetry of incentives between leaders and followers. We do not find momentum for women.