Does Divisional Play Lead to More Pennant Races?
建立了一个分析模型来预测体育联盟中出现冠军争夺战（即前两名球队胜场差不超过m场）的概率，并用美国职棒大联盟50个赛季的数据验证了模型的有效性，最后给出了确保分区增加冠军争夺战数量的条件。
A “pennant race” occurs in a sports league if the top two teams in a league finish within m̄ games of each other. We develop an analytical model that can be used to predict the probability that a sports league will have a pennant race. The model is then tested on data from the last 50 major league baseball seasons and is shown to do a remarkable job of predicting the number of pennant races that actually occurred. Finally, we give conditions which ensure that dividing a league of 2n teams into 2n-team divisions will increase the expected number of pennant races. As a corollary to this result we prove that the divisional structure which maximizes the expected number of pennant races must contain no divisions with 4 or more teams.