Courts, compatriots, and collusion: Evidence of collusion in professional squash

Collusion among opponents in professional sports has become a topic of interest in applied sports economics. It is difficult to uncover evidence of collusion, or truly any kind of cheating in professional sports, but empiricists have recently made progress in this area. If it exists, collusion is important as it has implications for the sport itself, the betting market surrounding the sport, and the study of human behavior and decision making. Here, we use data from professional squash to search for evidence of collusion among opponents in professional tournaments. In this context, collusion refers to match-fixing, that is, one player purposefully losing a match to an opponent when the win matters significantly to the opponent but not to the player. Our unique data set comes from the merging of data gathered from the Professional Squash Association and SquashSite, a well—known and trusted website devoted to the sport. Our primary research questions are threefold. First, can we uncover evidence of collusion in professional squash as has been done in a small number of other sports? Second, is collusion in squash largely a gender-specific phenomenon, as has been argued for other sports? Third, is collusion more prominent among players from the same nation, and by how much? Professional squash, we argue, is uniquely qualified with regards to this last question. It is an international sport, a two-player sport, and the number of nations represented among the top players is not so large to make the potential issue a minor one. We use a variety of empirical techniques in attempt to answer these questions. These include statistical hypothesis testing, regression analysis, and propensity score matching.