If you are a baseball fan, you might know the batting average or on-base percentage (OBP) of your favorite player, such as Yasiel Puig or Dustin Pedroia (two of prior probability‘s favorite players). But do you know your favorite player’s “Run Production Average” or RPA? According to Mike Gimbel, one of the pioneers in the field of sabermetrics (or the use of statistical methods to analyze player performance in baseball games), “The RPA is a comprehensive rating that takes into account offensive ability, defensive ability, pitching, the position played, the stadium where the performance took place, the age of the player and even his minor league performance.” More precisely, the RPA is a combined statistic that assigns the following weights to each of the following events:
| Single | = | .29 runs |
| Double | = | .41 runs |
| Triple | = | .70 runs |
| Home Run | = | 1.44 runs |
| Walk, Hit-By-Pitch (HBP) & Reached-on-an-error | = | .165 runs |
| Extra Base taken as a runner | = | .075 runs |
| Stolen Base, Wild Pitch & Balk | = | .100 runs |
| Caught Stealing & Picked-off | = | -.165 runs |
| Ground into Double Play | = | -.165 runs |
For more on the life and times of Mike Gimbel, check out this recent article by Hua Hsu on Grantland
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