Most of the stats discussed on this blog are either from or

Here are a few of the stats quite commonly mentioned:

  • WAR stands for Wins Above Replacement and is a measure of how many wins a player was worth as compared to a replacement-level player. The exact method of determining WAR is complex, and it differs between and Fangraphs. Commonly on this site, then, you may see the designations bWAR and fWAR if the numbers are drawn from one of those two particular web sites.
  • OPS is on-base percentage plus slugging percentage. OPS+ is a normalized version of OPS that takes into account both the league-wide average OPS as well as the player’s home ballpark. A value of 100 is considered league-average, while over 100 is better than average.
  • ERA+ is similar to OPS+ in that it has been normalized to the league-wide average ERA and the player’s ballpark. 100 is average, while over 100 is better than average.
Game Score (explanation taken from B-R page here):
  • This is a value created by Bill James that evaluates how good a pitcher’s start was.

    Start with 50 points. Add 1 point for each out recorded, (or 3 points per inning). Add 2 points for each inning completed after the 4th. Add 1 point for each strikeout. Subtract 2 points for each hit allowed. Subtract 4 points for each earned run allowed. Subtract 2 points for each unearned run allowed. Subtract 1 point for each walk.

Please add any requests in the comments below for more terms to be explained here.