During the 2017 NCAA football season, David Burge proposed a simple, easy-to-comprehend system for determining which NCAA football teams would be invited to the four-team playoff - the "marble game." The rules of the game are simple:
- Each team starts with a pre-determined amount of marbles.
- If a team wins a home game, they take 20% of the loser's marbles.
- If a team wins a road game, they take 25% of the loser's marbles.
- Neutral site games are treated as home wins for the victor (20% marble transfer).
The motivation behind the #marblegame is simple:
The point of the #MarbleGame is that CFB playoff selection could be simple, open, & transparent, not backroom committees lobbying for the outcome of a beauty contest.— David Burge (@iowahawkblog) December 3, 2017
marblr package allows R users to simulate the marble game for NCAA football seasons from 1995 to 2017 (data scraped from Massey Ratings). The
marble_game function takes four inputs:
ncaa_games: A dataframe that comes with the
marblrpackage with game result data scraped from Massey Ratings.
yr: A four-digit year from 1995 to 2017, indicating the desired football season.
wk: A integer to determine the maximum week of the season to include. By default, it will pull all available weeks. If you want to limit to the first 6 weeks of the season, you would set this parameter to 6.
p5_value: An integer to determine the initial marble count given to teams from the 2017 Power 5 conferences (ACC, Big 10, Big 12, Pac 12, SEC, and Notre Dame) at the start of a season. This defaults to 120 for teams from the Power 5 and 100 for all other schools.