Glossary of Pitching Statistics Hitting | Fielding

Linear Weights  KLWTS=

=  --------     Opponent's batting average on Balls Put In Play

BIP% vs Team
= BIP%-Team BIP% A pitcher's ability to prevent hits on Balls Put In Play,                                                          independent of team defense.

=   ---------  * 100   A player's ERA Park Adjusted and compared to the league average
              Lg ERA

FIP% - Fielding Independent Pitching - (HR*13+(BB-IBB+HB)*3-K*2)/IP + F

Where F is a league-dependent factor used to make the stat resemble ERA. The 2006 factors are 3.22-NL and 3.26-AL.

                        ERA+         Simpler and more accurate than PR in accounting for a pitcher's
IP*ERA+ = IP * (  ------ - 1 )   longevity and effectiveness.  In my Top 100 List, I divide it by 3 to  
                         100           make it close to DPOR, allowing for good hitter/pitcher comparisons.

=    ---------           Rough percentage of a team's defense made up by ONLY pitchers

             Regular Season ERA
PERA+     --------------------------  * 100
Measures how much a pitcher stepped up or
      Postseason ERA                choked during the playoffs.

PLWTS - .47*1B + .78*2B + 1.09*3B + 1.4*HR + .33*(BB+HB) - .26*(AB-H-GIDP)-.72*GIDP

In our Pitcher Stats section, we do not include stolen base data in our calculation. This is primarily because we do not have it handy, although it could be a blessing in disguise as many pitchers don't have a huge effect on basestealing effectiveness.

=  --- * (Lg ERA- ERA)  Pitching Runs- Runs saved beyond what a league average pitcher
        9                                                      would save.

PR+ Adjusted Pitching Runs- Pitching Runs adjusted for home ballpark effects

Park = PR - PR+  Quantifies the home ballpark effect for a pitcher's entire career:
                          Positive = Pitcher's Parks, Negative = Hitter's Parks

= -------     Unearned runs allowed per inning pitched

WAT Original Formula:

= Decisions * (Pitcher W%-Team W%)    Wins Above Team

Total Baseball jazzed it up for reasons that I do not find clear:

WAT= Decisions * (Pitcher W%-Team W%)
                  2 - 2 * Team W%

= Pitcher W% - Team W%   Allows for career "ability to win" comparisons between players                                                       with disparate career innings pitched.