The Puck Stops Here

I have looked at the hockey sabermetrics problem of adjusting +/- ratings this summer. I have shown two methods to do this. One as a rate stat and one as a counting stat. It is clear that there is a lot of information in +/- ratings, but the interpretation of getting it out in a meaningful way is non-trivial.

One way to look at the problem, which to my knowledge nobody has done, is to calculate a player's goals for average and goals against average, while simultaneously calculating the time averaged goals for and against averages of the players on the ice who play against the player. In this way, it is possible to remove the issue of quality of opposition. Each player will have a GFA and a GAA as well as an opposition averaged GFA and GAA. An offensive and defensive +/- rating can then be calculated as the difference between a given player's GFA (or GAA) and that of his opposition.

The statistics exist to do this, but it is a non-trivial task to parse all of the gamelogs in order to determine who played against whom. This is a task I have begun and hope to produce results later on this summer. I think it will be a step forward in understanding +/- ratings.