Detecting Collusion

Did the Soviets Collude? A Statistical Analysis of Championship Chess 1940-78 (with John Nye), Journal of Economic Behavior and Organization (2009), 70 (1-2): 10-21.
    Abstract: We expand the set of outcomes considered by the tournament literature to include draws and use games from post-war chess tournaments to see whether strategic behavior can be important in such scenarios. In particular, we examine whether players from the former Soviet Union acted as a cartel in international all-play-all tournaments - intentionally drawing against one another in order to focus more effort on non-Soviet players - to maximize the chances of some Soviet winning. Using data from international qualifying tournaments as well as USSR national tournaments, we consider several tests for collusion. Our results are inconsistent with Soviet competition but consistent with Soviet draw-collusion that yielded substantial benefits to the cartel. Simulations of the period's five premier international competitions (the FIDE Candidates tournaments) suggest that the observed Soviet sweep was a 60%-probability event under collusion but only a 25%-probability event had the Soviet players not colluded.  (104 Kb, Spring 2008)

Retailer Entry Conditions and Wholesaler Conduct: The theatrical distribution of motion pictures (prior version was "Testing for Collusion" and before that "Measuring Market Power"), complete version linked but a shorter version is forthcoming in International Journal of Industrial Organization (2008), 26(4): 966-84.
    Abstract: I add to the empirical literature on vertical contracting and wholesaler conduct by using retailer entry conditions to infer unobserved choice variables and equilibrium responses to prices and advertising. After estimating the US demand for theatrical motion pictures from 1990-96, I apply these techniques to compare predictions under various distributor-conduct hypotheses to observed outcomes. While several caveats apply, results indicate that the hypothesis of competition among distributors fails to describe advertising levels or aggregate payments of theaters to studios. The hypothesis of some collusion among distributors, however, matches the data fairly well. (352 Kb, March 2007)

A New Test for Monopoly with Limited Cost Data, Economics Letters (2012), 117: 891-4.
    Abstract: The test’s intuition is that demand estimates in isolation may diverge from demand estimates under joint estimation with cost if the monopoly null hypothesis is false. Simulations indicate that the test can have substantial power using duopoly data.   (355 Kb, December 2012)