Recent Discoveries   <- Talks   <-  Sean Forman   <-  You Are Here

   / /

DIPS

• There are several possible outcomes for any pitched ball.
  • Strikeout

  • Walk/Hit Batsman

  • Ball put into play resulting in Home Run

  • Ball put into play resulting in an out

  • Ball put into play resulting in a single, double or triple

• The pitcher has direct control over the first three, and there is a strong correlation between the players who lead these statistics from year to year. Nolan Ryan, Greg Maddux, Kerry Wood, Billy Wagner

• The last two are affected by the defense and can be summarized by Batting Average on Balls in Play (BAbip).

• Voros McCracken found that BAbip is only weakly tied to the pitcher, and there is very little consistency in who leads this statistic from year to year. It is primarily the result of defense and luck.

• You can compute a defense-independent ERA (dERA) based on the first three factors and this is a better predictor of next year's ERA than the current year's ERA is.

• TAKEN FROM LAST YEAR's TALK

• Possible overrateds for 2005 (Low ERA, High Dips ERA):
  • Jose Lima (4.07 -> 6.99),
  • Jake Westbrook (3.38 -> 4.49),
  • Jason Marquis (3.71 -> 4.13),
  • Brandon Webb (3.59 -> 3.54),
  • Odalis Perez (3.25 -> 4.56),
  • Carlos Zambrano (2.75 -> 3.26),
  • Jake Peavy (2.27 -> 2.88),
  • Al Leiter (3.21 -> 6.13)

• Possible Underrateds for 2005 (Low Dips ERA, High ERA):
  • Derek Lowe (5.42 -> 3.61),
  • Jon Lieber (4.33 -> 4.20),
  • Jason Johnson (5.13 -> 4.54),
  • Sidney Ponson (5.30 -> 6.21),
  • Jeremy Bonderman (4.89 -> 4.57),
  • John Lackey (4.67 -> 3.44)

• Overrateds for 2006: Jarrod Washburn, Bruce Chen, Joe Blanton, Kevin Millwood, Jeff Suppan, Tim Hudson, Jason Marquis

• Underrateds for 2006: Chris Young, David Wells, Jeremy Bonderman, AJ Burnett, Esteban Loaiza, Corey Lidle, Brian Lawrence, Mark Redman

/