Here’s a recap on the Massey Ratings that Jamie Flynt summarized as well as included info from the Massey’s report. To learn more about the Massey Ratings and how you can support his efforts for women’s football, go to www.masseyratings.com.
A rating systems assigns each team a single numerical value to represent that team’s strength of schedule relative to the rest of the league on some predetermined scale. This rating changes when new games are played. Example: Team A is rated at 20 while Team B is rated at 15. The expected outcome is A-B= 5, do Team A should win by 5 points while Team B is the underdog. (rating goes in the opposite direction of ranking)
In Massey’s mathematical formulas, each win is either a 1 (win), -1 (loss), or a 0 (tie/no play).
In order for this rating system to work, some chain of opponents must link all teams together (one of the actual good things about playing outside of the conference). Since some NWFA teams have moved to the IWFL, we can actually link teams from both leagues in one rating…but this might not be actual as teams have turnover, injuries, etc.
The results of all teams playing each other are put into a matrix (mathematical formula) as either a win, loss, or tie/no play. The points won by is listed also. After some calculating using formulas, a rating is made.
Example: Team A beats Team B 10-4
Team C beats Team D 5-3
Team A ties Team C 9-9
Team B beats Team D 27-9
These wins (1s) and losses (-1) and ties (0) are put into some fancy math. It utilizes prior performance to determine if a team will win. So Team A will more than likely beat Team D since it’s rating is higher than Team D.
A team’s rating is the mathematical sum of its average margin of victory and its average schedule strength. It goes beyond wins and points to determine how much respect a team really deserves for its performance. Success, especially against strong opponents, translates to a high rating.
Home field advantage – If the home team is to gain a benefit by playing at home. Some choose not to put this in the rating as the “advantage” is arbitrary.
For some ratings, since margin of victory is the only statistic upon which the ratings are based, a team can improve its rating by running up the score. However, it’s possible for a team’s rating to decline unfairly after a victory over a pathetic team because it didn’t win by enough points to compensate for the opponent’s weakness.
In the Massey Rating a win counts, but the points spread doesn’t count so much (which is good for blowouts). It’s just a win or a loss or a tie. A 81 point win is the same as a 4 point win.
Offense and Defense Ratings
This is the team’s ability to score points (offense) and prevent opponents from scoring (defense). You get the rating by subtracting offense of Team A –Defense of Team B.
Ex. Team A Offense Rating (34) Defense Rating (7)
Team B Offense Rating (40) Defense Rating (-2)
Team A offense – Team B defense = 36
Team B offense – Team A defense = 33
So the predicted score is 36-33 or a 3 point margin.
Some games are weighted more than others. More recent games are better indicators of a team’s current strength. Also discounting games between an overmatched opponent can be addressed by weighting close games more than blowouts,
Team ratings are based on a lot of things. In order to get a rating, all teams need to be linked somehow (playing out of conference). This gives an initial rating. After each game is played, the rating is recalculated based on wins and losses, not by the points difference. The only time a team’s point spread is used is to calculate team offense and defensive ratings.