# CAIN: Counting a Pitcher’s HR/FB Out-Performance

Dave Cameron recently posted an interesting article about Jhoulys Chacin. It’s all about how Jhoulys Chacin is defying the rules of HR/FB rates. His HR/FB rate this year is a mere 2.8%. Jhoulys Chacin has pitched 120 innings, had 106 fly balls, and allowed just three home runs. Very impressive. But it makes you wonder if there are other pitchers who are maintaining low rates while allowing more fly balls overall. Because while Jhoulys Chacin is obviously benefiting from his HR/FB ratio, it’s possible for a pitcher to have more fly balls while maintaining a slightly higher HR/FB and benefit more. So I invented CAIN, a counting stat to help measure that.

CAIN does not stand for anything. I’m just paying homage to a famous outlier.

CAIN = FB – (9.34 x HR)

To explain, the Fangraphs Glossary says that the league-average fly ball rate is “~9-10% depending on the year”. In fact, of the 91 qualified pitchers in Fangraphs database for 2013, the average HR/FB ratio is 10.7 percent. So there are 9.34 fly balls for every homer. So we can say that for most pitchers, if they had ten homers at this point in the season, they would have about 93.4 fly balls.  Ten homers and 93.4 fly balls would give you a CAIN of exactly 0. Make sense?

Now for what you came here for. Here are the top ten in CAIN this year:

Note that I’m not saying any players might actually be able to sustain their CAIN, I just think it’s an interesting little tidbit, and perhaps a nice follow on to Dave Cameron’s article.

Name Team IP HR FB CAIN HR/FB
Eric Stults Padres 133 8 163 88.3 4.90%
Jhoulys Chacin Rockies 120 3 106 78 2.80%
Bartolo Colon Athletics 135.2 9 161 76.9 5.60%
Travis Wood Cubs 128.1 10 159 65.6 6.30%
Adam Wainwright Cardinals 154.2 6 113 57 5.30%
Bud Norris Astros 119.2 10 150 56.6 6.70%
Lance Lynn Cardinals 122 7 121 55.6 5.80%
Matt Moore Rays 116.1 8 130 55.3 6.20%
Derek Holland Rangers 133.2 9 137 52.9 6.60%
Clayton Kershaw Dodgers 152.1 9 136 51.9 6.60%

And Jhoulys Chacin is not #1. It turns out that Eric Stults is in fact benefiting more from his HR/FB rate outlier this year. Of course, that’s partially happening in Petco. Petco is not Coors.

Name Team IP HR FB CAIN HR/FB
Joe Blanton Angels 116 24 133 -91.2 18.0%
Roberto Hernandez Rays 113.1 18 91 -77.1 19.8%
Jason Marquis Padres 117.2 18 99 -69.1 18.2%
CC Sabathia Yankees 142 23 150 -64.8 15.3%
Chris Tillman Orioles 119.2 21 135 -61.1 15.6%
Ryan Dempster Red Sox 115.2 20 130 -56.8 15.4%
R.A. Dickey Blue Jays 134.2 23 163 -51.8 14.1%
Jeremy Guthrie Royals 126.2 22 155 -50.5 14.2%
Hisashi Iwakuma Mariners 138.1 21 146 -50.1 14.4%
Lucas Harrell Astros 112 15 96 -44.1 15.6%

Poor Joe Blanton. His peripherals aren’t that bad this year. But he’s been posting some pretty high HR/FB rates for the last five years or so. I’ll leave it to someone else to puzzle that out.

After doing this analysis I wanted to know about exceptional seasons in the “UZR era” for pitchers’ CAINs. I am continuing to use 9.34 as the FB/HR value, not adjusted for year. If I was being very scientific I would probably break that constant out for league AND year, but I’m lazy and unpaid. Anyway, here, unsurprisingly, is Matt Cain:

Season Name Team IP HR FB HR/FB CAIN
2011 Matt Cain Giants 221.2 9 246 3.70% 161.94
2007 Chris Young Padres 173 10 243 4.10% 149.6
2002 Jarrod Washburn Angels 206 19 317 6.00% 139.54
2009 Zack Greinke Royals 229.1 11 242 4.50% 139.26
2002 Mark Redman Tigers 203 15 273 5.50% 132.9
2011 Jered Weaver Angels 235.2 20 319 6.30% 132.2
2010 Anibal Sanchez Marlins 195 10 222 4.50% 128.6
2010 Livan Hernandez Nationals 211.2 16 278 5.80% 128.56
2010 Jason Vargas Mariners 192.2 18 295 6.10% 126.88
2007 Matt Cain Giants 200 14 255 5.50% 124.24

So in summary, CAIN is a nice little tool if you are interested in seeing just how much a HR/FB rate is affecting a pitcher’s performance. If anyone can think of a better acronym, like one that actually is an acronym, please leave a comment.

White Sox fan.