Again, we delve into the mysteries that are sabermetric concepts in this weekly feature. If you've ever been mystified when we throw a statistic out there, this is the feature for you.
This week, we are going to talk about one of the biggest factors to a pitcher's success. Maybe. It's complicated, but we'll get to that.
See, pitching and defense kind of go hand in hand. Think about Bull Durham, when Crash tells the impressionable Nuke to throw more ground balls, because strikeouts are fascist and ground balls are more democratic. Why? Ground balls get everyone on the infield involved.
Like it or not, a pitcher is dependent to a degree on the fielding behind him. As good as Wandy Rodriguez may have pitched in his last two games, he was undone to various degrees by shoddy defense behind him. Will that be the case tonight against the Nationals?
The relationship between the two is the reason why Defense Independent Pitching Statistics (DIPS) came about in the first place. Back in 1999, Voros McCracken came up with the first such stat, calling it DIPS and trying to adjust for the fielding behind a particular pitcher. It was a great concept, new to baseball analysis, but the formula was a bit clunky and made some assumption that needed to be cleaned up. Let's talk about what exactly a pitcher can and cannot control after the jump...
The pitcher is one man on the mound, but he's arguably one of the most important defensive players. He starts every play by throwing the ball to home plate, and how he does that affects all eight other guys on the field. A good shortstop can shade left or right to adjust for whatever breaking ball the pitcher may be throwing. Every play, though, starts with a throw.
That should then track that pitchers are very dependent on the fielding behind them, right? A team that commits a bunch of errors won't have as successful a pitching staff as one who vacuums up everything, right?
The truth of that Bull Durham quote is a pitcher does control some things. He can walk batters, putting men on base all by himself. He can pick up outs by striking guys out all by himself. He can also give up monster home runs, putting runs on the board all by himself.
What statistics like FIP and DIPS attempted to do is take the subjectiveness of fielding out of a pitcher's statistics and try to normalize the league. That way, we could really get a picture of who the best of the best were.
The problem with DIPS was it assumed a pitcher couldn't control the defense behind him. Essentially, it ignored the value of good ground ball pitchers. Wandy Rodriguez sort of fits that mold. He has been one of the best pitchers for Houston for a few years now, but has never had the best strikeout rate. He doesn't walk guys and has a killer curve that can either get strikeouts or easy grounders. How do you quantify that in DIPS?
Well, you don't, which is why Tom Tango developed Fielding Independent Pitching (FIP). What this did was basically the reverse of Batting Average On Balls In Play (BABiP). Instead of taking out home runs, walks and strikeouts, that is all we are going to look at. But, it's going to be scaled to the innings pitched.
The thing you should remember about FIP, though, is its a made-up number. ERA, for all its interesting deficiencies, is an elegantly simple formula, based on one of the most important aspects of the game: runs scored. Take the number of eard runs, divide by innings pitched and multiply by nine. Voila! You've got the number of runs a pitcher can be expected to give up in nine innings of work.
FIP is not that. Runs don't come into the equation (literally), which is why Tango added a 3.10 to the number, making it look like ERA. That way, we can compare a guy's FIP to his ERA and judge whether he's been victimized by his defense a bit.
That still doesn't get the whole way to figuring out how well a pitcher does on his own. The reason why is the number of home runs a pitcher gives up can fluctuate based on how many fly balls he gives up.
Dave Studemond of The Hardball Times tweaked FIP by adding in the league average for home runs per fly ball to the formula. With that, he created a very good judge of what a pitcher's future ERA will look like. In essence, he took a stat that was telling us how well a pitcher did without the defense being involved and made a way to predict how well he will continue to do.
Let's tie all this together with Wandy. We know a pitcher can't always help the defense behind him. But, judging by Wandy''s very good 2.38 ERA and his equally good 2.44 FIP show he hasn't been hurt by the bad defense behind him. However, that's not all we can learn. Wandy's xFIP is a full "run" higher than both of those at 3.79.
The reason for that is Wandy has yet to give up a home run in 11 1/3 innings. That won't last, especially since he's given up one homer per nine innings in his career. Add in a low K rate and there are reasons why his success could regress a bit. But, if he raises that K rate to his career norms, there's also a chance he will continue pitching well, even with the home runs.
After his last start, Brad Mills made the point that the errors hadn't really hurt Wandy for a "big inning." For the most part, he's been right. We can see through FIP that Wandy has really pitched well despite his defense. That's at least a positive heading into tonight's start against the Nationals, right?