Commentary

The true value of FIP

Updated: June 9, 2010, 11:30 AM ET
By AJ Mass | ESPN.com

Lost in all the hoopla of Jim Joyce's call at first base during Armando Galarraga's attempt at perfection was the fact the Detroit Tigers pitcher was lucky to still have been in a position to make history. If not for Austin Jackson making a spectacular grab on Mark Grudzielanek's fly ball, the Indians would have had their first hit a couple of batters sooner, and with zero controversy.

Pitchers, in fact, have very little control over what happens once balls get put into play. Bad hops, bounced throws, balls that fall into the stands just out of the reach of an outstretched glove -- there's nothing a pitcher can do about any of those things, except shrug his shoulders and forge on. Through the sabermetric work of Voros McCracken, Tom Tango and others, it became very clear that in order to truly measure the impact on the result of a game made by an individual pitcher, you had to take defense out of the equation. And thus, a new stat, Fielding Independent Pitching (FIP) was born.

What is FIP? It's a measure of how successfully a pitcher takes matters into his own hands, for better or for worse. Combining home runs allowed, walks and strikeouts -- none of which the defense can do anything about -- FIP creates a single number that attempts to be a better predictor of a pitcher's future ERA than his ERA itself.

A Basic FIP Formula: FIP = [(13*HR) + (3*BB) - (2*K)]/IP + 3.10

Proponents of FIP would have us believe that if a pitcher's ERA is far lower than his FIP, we should expect a regression the following season. Similarly, if a pitcher has a higher ERA than FIP, then he was probably more unlucky than anything else, and due for a bounce-back campaign. So how does that play so far in 2010? Let's go to the leaderboard and see:

Certainly the season is not over yet, but even though every single one of these current ERA leaders who pitched in the majors last year has a lower ERA in 2010, only four were "predicted" to do so. The argument gets even less convincing if you decide to use FIP during a season to predict an ERA regression. Take a look at the six pitchers considered least likely to maintain their current levels of success:

These are all names currently in the top 10, which quite frankly is the obvious place to expect regression -- at the top, back toward the league average. It's not really useful information. I suppose one could argue that Livan Hernandez could well finish this year with an ERA of 4.00 and satisfy both the current prediction that he's due for a regression this season, as well as the prediction that he would better his 5.44 ERA from 2009, and use that as "proof" that FIP works. It seems to me, however, that this particular use of FIP is misguided.

Let's say a pitcher's FIP does indicate that his ERA "should" be lower than it is, because his defense has let him down. Well, if his defense isn't changing -- meaning he's going to continue to have the same basic starting lineup behind him for the rest of the season -- then why should we expect a change in its impact on his ERA? A ground ball pitcher stuck in front of an infield with zero range is simply going to continue to suffer the consequences. In fact, if you think about it, a bad defense behind a pitcher might well help his ERA in the long run by committing errors that add to the unearned run totals in lieu of runs of the earned variety.

That's not to say I don't think FIP can be a useful tool. You just have to use it as a guide to what it truly measures: a pitcher's ability to control the outcome of his start without any outside influence. The pitchers with the most control over a game's outcome -- and thus, the lowest FIP -- are the ones who are least impacted by outside factors, be they defensive ability, ballpark conditions or luck. It is these pitchers, whose pitching exploits most often end up in one of the three true outcomes, who you can most rely on to maintain the status quo, for better or for worse. These are the pitchers you can count on. In the case of Roy Halladay and Ubaldo Jimenez, that's a good thing. For Randy Wells and Felipe Paulino, not so much.

Here are the pitchers who are what the stats say they are:

The following table shows us the pitchers who have the least control of their own fates. As such, they fall victim to bad breaks and balls hit just out of the reach of a diving outfielder far more than the previous list. Some of these guys may indeed simply be bad. Others, like Ian Kennedy and his .229 batting average against, might be in for a rude awakening as the summer drags on.

AJ Mass is a fantasy baseball, football and college basketball analyst for ESPN.com. You can follow AJ on Twitter or e-mail him here.