Pedings, “Bracketology: How can math help

Every year, people across the United States predict how the field of 65 teams will play in the Division I NCAA Men’s Basketball Tournament by filling out a tournament bracket for the postseason play. This article discusses two popular rating methods that are also used by the Bowl Championship Series, the organization that determines which college football teams are invited to which bowl games. The two methods are the Colley Method and the Massey Method, each of which computes a ranking by solving a system of linear equations. The article also discusses how both methods can be adapted to take late season momentum into account. All the methods were used to produce brackets in 2009 and their results are given, including a mathematically-produced bracket that was better than 97 % of the nearly 4.5 million brackets submitted to ESPN’s Tournament Challenge.