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.