The Bias of Schedules and Playoff Systems in Professional Sports

We examine the method used for seeding teams in professional sports leagues after the regular season has ended. In particular, we are interested in which teams are in the playoffs and which of these playoff teams get the home field advantage and/or a first round bye. We show that the regular season schedule is biased against good teams (since teams are separated into divisions) and that in addition to the current schedules and their inherent biases the playoff systems add more bias against good teams (since division winners are typically ranked higher than nondivision winners). The amount of bias in various cases is presented. Furthermore, we present necessary and sufficient conditions for a schedule to be completely unbiased. Using this condition we develop schedules which maximize intradivision rivalries while maintaining no bias.