The Colley and Massey methods are two mathematical algorithms that use linear algebra to rank sports teams. Both use the network of interconnections formed by the match-ups between teams that occur over the course of a season to produce a full ranking of all the teams, even though each team plays only a subset of the other teams in the nation. In essence, the Colley method uses strength of schedule to produce its ranking; the Massey method employs strength of schedule together with margin of victory. All 7627 games between Division I opponents occurring in the 2018 season, from February 16 through May 21 (just before the start of many conference tournaments), were used to produce these rankings. We use uniform weighting: each game is treated equally.
The Colley ranking is one of the six objective methods used to rank NCAA FBS college football teams. Another one of these methods was also designed by Kenneth Massey, who invented the eponymous method used here, but the Massey algorithm employed in college football is not the same as the method we use.
You can contrast these rankings with a number of NCAA Division I Baseball Rankings available from the NCAA, including RPI and poll-based methods, and with the Massey Ratings for NCAA Division I Baseball.
Rankings for All Division I Teams
Colley Ranking |
Massey Ranking |
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References
- Boyd’s World, database for scores of college baseball games.
- Who’s #1?: The Science of Rating and Ranking, Amy N. Langville and Carl D. Meyer, Princeton University Press, 2012.
