Do Basketball Scoring Patterns Reflect Illegal Point Shaving or Optimal In-Game Adjustments?∗ Jesse Gregory University of Wisconsin, NBER
[email protected] Current Version: August, 2017 Abstract This paper develops and estimates a model of college basketball teams’ search for scoring opportunities, to provide a benchmark of the winning margin distributions that should arise if teams’ only goal is to win. I estimate the model’s structural parameters using first-half play- by-play data from college games and simulate the estimated model’s predicted winning margin distributions. Teams’ optimal state-dependent strategies generate patterns that match those previously cited as evidence of point shaving. The results suggest that corruption in NCAA basketball is less prevalent than previously suggested and that indirect forensic economics methodology can be sensitive to seemingly innocuous institutional features. JEL Codes: C61, L83 K42 ∗I am grateful to John Bound, Charlie Brown, Morris Davis, Robert Gillezeau, Sam Gregory, Dmitry Lubensky, Brian McCall, Mike McWilliams, Todd Pugatch, Colin Raymond, Lones Smith, Chris Taber, Justin Wolfers, and Eric Zitzewitz for helpful comments. All remaining errors are my own. Measuring corruption is inherently difficult because law-breakers cover their tracks. For that reason, empirical studies in forensic economics typically develop indirect tests for the presence of corruption. These tests look for behavior that is a rational response to incentives that only those who engage in the particular corrupt behavior face. The validity of these indirect tests depends crit- ically on the assumption that similar patterns do not occur if agents only respond to the incentives generated by the institutions that govern non-corrupt behavior.