After getting shelled by the Texas Rangers on June 2nd, 2010 (2.2 IP, 6 earned) Gavin Floyd’s ERA weighed in at a rotund 6.64, to the uninitiated it would appear that he was having a terrible season, but what is the truth? During Floyd’s early season struggles it was pretty clear that luck was not on his side as his BABIP in April was 369 and in May slightly better but still high at 343, while his strand rates during those months were 55.8% and 66.8 un-respectively. Floyd is throwing harder (FB velocity 2009-91.8, 2010-92.4), missing just as many bats (2009 contact%-77.8, 2010-77.0) and even getting hitters to chase his pitches more often (2009 o-swing%-27.6, 2010-28.3).
Someone in my fantasy league made a comment regarding Floyd’s terrible season and I commented “outside of a brutal BABIP and low strand rate, Gavin Floyd has essentially been the same pitcher” to which I was basically ridiculed. But as we can see from this chart, Gavin Floyd was and is the same pitcher and therein lays the beauty of advanced pitching metrics like FIP or xFIP and the use of the peripherals that help gather these stats (BABIP, strand rate, HR/FB etc).
When we look at K/9, BB/9 and xFIP from April all the way through this year and even from last season’s totals we see what xFIP is attempting to do for us, take out all of the noise and some of the factors pitchers cannot control (such as what happens after the ball is put in play) and give us a real idea of how said pitcher is performing, relatively speaking.
Look at how steady the xFIP column is in particular, even when Floyd had a month in which his ERA was 6.49, his xFIP remained calm and cool at 4.09. But just as important look at his unbelievable Bob Gibson-like 1.01 ERA from July, again his xFIP tempers this and brings us all back to planet earth as it checks in at 3.35.
This is simply breaking down who Gavin Floyd is as a pitcher and this is also a simple way to explain and show the value and usage of xFIP. I think it also helps show how useless ERA really is when evaluating a pitchers overall value and performance.
For those curious, since that June 2nd shellacking Floyd has gone on a hellacious run – 62.1 IPs, 45 hits, 14 BB – 52 K’s, good for a 1.74 ERA and 0.95 WHIP. All things considered Floyd is having a career year, who would’ve guessed?
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FIP: Fielding Independent Pitching, a measure of all those things for which a pitcher is specifically responsible. The formula is (HR*13+ (BB+HBP)*3-K*2)/IP, plus a league-specific factor (usually around 3.2) to round out the number to an equivalent ERA number. FIP helps you understand how well a pitcher pitched, regardless of how well his fielders fielded. FIP was invented by Tangotiger.
xFIP: Expected Fielding Independent Pitching. This adjusts FIP and “normalizes” the home run component. Research has shown that home runs allowed are pretty much a function of fly balls allowed and Home Park, so xFIP is based on the average number of home runs allowed per outfield fly.