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Tuesday, December 29, 2009
Mike Silva Chronicles - Part 4: FIP
FIP is the one advanced metric that intrigues me. My issue is that is favors players with a large number of strikeouts. A good pitcher doesn’t always have to strike people out, but could still make quality pitches that generate outs.
The formula for FIP is:
(13*HR + 3*[BB+HB-IB] - 2*SO) / IP + 3.2
That “3.2” is just to align it to ERA. Otherwise, the point is that if you can keep your HR down, your BB and hit batters down, and your K up, then you will have a low FIP.
This makes it seem that all “contact plays� are the design of luck, which I think you would agree is not the case.
This is true, that not all contact plays are the same. But, do we have an issue with OBP? What does OBP say: all walks, singles, and HR are worth “1”. Does that make any sense? No, of course not. But, OBP is just one component to offense. There’s also moving runners over, as well as baserunning.
FIP is the same thing: it is only concerned with one component to pitching. And that component is the one that does not involve his fielders. The interesting thing with FIP is that the players wtih the best FIP are also the ERA leaders. For example, here’s the top 10 FIP of pitchers born since 1962, minimum 10,000 batters faced:
FIP
2.99 Martinez Pedro
3.28 Clemens Roger
3.33 Johnson Randy
3.33 Schilling Curt
3.34 Maddux Greg
3.35 Smoltz John
3.48 Brown Kevin
3.55 Saberhagen Bret
3.60 Gooden Dwight
3.68 Mussina Mike
And here are the top 10 in ERA, under the same criteria:
ERA
2.93 Martinez Pedro
3.12 Clemens Roger
3.16 Maddux Greg
3.28 Brown Kevin
3.29 Johnson Randy
3.33 Smoltz John
3.34 Saberhagen Bret
3.46 Schilling Curt
3.46 Cone David
3.51 Gooden Dwight
Look at the names. Pedro is #1 in either case, as is Clemens. Even Maddux doesn’t move much. Schilling and RJ are on both lists, as is Smoltz and Kevin Brown and Bret Saberhagen and Dwight Gooden. In fact, there is only one player different in the top 10: Mussina is #10 in FIP (he was 12th in ERA), and David Cone is #9 in ERA (he was 11th in FIP).
This is the revelation of DIPS and FIP: even though we completely ignored the number of hits a pitcher allowed (COMPLETELY) we were still able to get a top 10 list using only HR, BB, and SO that pretty much matched their ERA. That’s astounding isn’t it?
So, the purpose of FIP is not to dismiss hits allowed and other non-HR contact plays, but simply to break it up into its own component (fielding-independent pitching, FIP). And, the fantastic byproduct of doing that is that even if you dismiss hits allowed and other non-HR contact plays, you STILL get a very similar answer.
There are exceptions of course, as with everything. Tom Glavine’s career FIP is about 0.50 runs worse than his career ERA. This signals that Glavine does something extra, either he can sequence his events better (leaves alot of runners on base for example), or he has better control on his balls in play. And Javy Vazquez’s ERA is about 0.30 runs worse than his FIP, which signals something different, that perhaps he gives up alot of doubles, or doesn’t sequence his events well, etc.
Overall, two-thirds of pitchers will have their FIP and ERA be within 0.20 runs of each other, and almost all will be within 0.40 runs of each other.
That’s the power of FIP: that it’s designed to tell you one specific thing, and it tells you a second, perhaps even more important, thing. This is perhaps the most important sabermetric finding in the last twenty years. And we all have Voros McCracken to thank.