Thursday, July 16, 2009

Why Roy Halladay matters

Roy Halladay went years pitching in virtual anonymity in Toronto. The location of his team and its inability to get to the playoffs meant he went unnoticed as baseball fans heaped praise upon contemporaries like Brandon Webb, CC Sabathia, Johan Santana, Josh Beckett and others.

All of a sudden, though, so many people are spending so much time talking about Halladay it seems like he's on the verge of being overrated. He's not really the best pitcher in baseball, is he?

Well, actually, if you look at the numbers, he is.

Pitchers can only control so much. They can control their strikeout rate. They can control their walk rate. They also can, to a large extent, control whether the hitter hits the ball on the ground or in the air. (Ground balls aren't as good as strikeouts, of course, but they tend to be far more harmless than fly balls.) It stands to reason that a pitcher who strikes out the most hitters, walks the fewest hitters and induces the most ground balls would be the best pitcher in the game.

To find that pitcher, I took strikeout-to-walk ratio (strikeouts divided by walks) and ground ball-to-fly ball ratio (ground balls divided by fly balls) and multiplied them together. The average pitcher has a K/BB ratio around 2 and a GB/FB ratio around 1.1, so your average pitcher would have a UPR (Ultimate Pitcher Rating) right around 2.2.

(By the way: I don't give enough credit here to and its unbelievable "Export to Excel" tool that allows you to export data and play around with it without having to retype it all or do all the calculations by yourself. It's a really, really fantastic system.)

Here's the leaderboard over the last four seasons (with ERA+ in parentheses):

Roy Halladay: 13.17 (151)
Joel Piniero: 10.92 (131)
Dan Haren: 9.43 (226)
Javier Vazquez: 7.80 (142)
Zack Greinke: 6.69 (204)

Roy Halladay: 10.56 (154)
Brandon Webb: 8.88 (139)
Derek Lowe: 8.60 (131)
Mike Mussina: 7.94 (132)
Dan Haren: 6.59 (138)

Derek Lowe: 8.42 (118)
Brandon Webb: 8.26 156)
Felix Hernandez: 8.21 (110)
Greg Maddux: 7.40 (98)
Tim Hudson: 7.17 (128)
(This was the year Halladay had a 3.71 ERA, his highest ERA since 2004. He ranked 11th on the leaderboard, right between Erik Bedard and John Smoltz, with a mark of 5.31.)

Brandon Webb: 14.45 (152)
Roy Halladay: 10.09 (143)
Derek Lowe: 8.65 (124)
Chris Carpenter: 8.05 (144)
Felix Hernandez: 6.89 (98)

It's not a perfect system, but it does say something about the pitchers that perform best in those aspects of the game they can control.

Two names stick out on the list. One is Brandon Webb, a pitcher who hasn't yet had an ERA over 3.60 in his major-league career. (The 13.50 ERA he compiled in his one start this season doesn't count.)

The other is Halladay, a pitcher who indeed may be the best in the game.


Anonymous said...

It's awesome to finally see a Red Sox reporter embrace sabermetrics. It amazes me that given the rabid atmosphere in Boston this is mostly ignored (the sentiment that, "JD Drew is a waste," for example).

Your stat here seems like a quick and dirty version of Base Performance Value, a stat developed by Ron Shandler. I can't highly enough recommend his book, Ron Shandler's Baseball Forecaster 2009.

BPV is a single number based on K/9, BB/9, and GB%. Using that metric Roy Halladay is #3 in the AL this year behind Greinke and Lester.

Keep up the good work,

floydiansea said...

Somewhere, the FJM Gods smile down upon you.