Tuesday, 23 February 2010

All Pitching, All the Time

That's the spirit of Nationals' coverage so far this season. We've had the excitement of Stephen Strasburg's bullpen session combined with the news that Mr Riggleman thinks he'll be starting the season in the minor leagues. We had Mr Riggleman's word that Drew Storen was headed in the same direction. Finally, we have all sorts of rumours.

I did a bespoke projection for Chien-Ming Wang just the other day, but this time, more as food for thought, I'm going to present the straight Marcel projected ERA for Nationals' rotation options as listed by CBS Sportsline. ERA is obviously earned-run average. FIP is one of those relatively newfangled sabermetric stats that gives a value to home runs, walks and strikeouts that can be turned into an ERA value. It has a better predictive ability than ERA. It's worth mentally adjusting it for defence, in that a good defence will reduce the FIP, and a bad one will increase it.
           ERA        FIP
Lannan 3.98 4.58
Marquis 4.23 4.35
Olsen 4.66 4.85 (shoulder injury)
JD Martin 4.41 4.81
Mock 4.76 4.21
Martis 4.37 4.76
Detwiler 4.26 3.95 (hip surgery)
Balester 4.83 4.90 (ribcage woes)
Stammen 4.42 4.45 (elbow chips)
Chico 4.65 4.72 (elbow surgery)
Wang 4.81 4.19 (shoulder surgery)

I've left off a few names, like Jordan Zimmermann, who isn't going to pitch this season, and some of the veterans lurking around the camp.

To say the least, we've got a lot of options. Also, there are some things that are hard to credit based on what we have seen so far, such as Balester posting an ERA under 5. Basically, going forward, one would expect on this basis to open the season with a rotation of:

Lannan, Marquis, Olsen, JD Martin and Mock.

Next man off the cab rank would be Martis, or maybe Chico. What will happen when Wang is fit is anyone's guess.

Of course, player options are going to play a part in the final outcome. And spring training will render these statistics more or less believable. After all, they are projections, not predictions.


Smitty said...

I've looked at FIP a little. In theory it seems valid but under some scrutiny, it seems to have holes. Maybe I'm clueless and just don't "get it", but is it strikeout centric? By eliminating the fielding component you denigrate groundball/pitch to contact guys like Lannan or Randy Jones (2 examples that pop into my head). Guys who strike out a paltry amount of batters (Lannan 4.6/9ip; Jones 3.3) and hence, Lannan's FIP has been much higher than his ERA.

I see the logic in that a pitcher has "control" over the strikeout and trying to measure a pitcher's ability independent of others. But doesn't he also have "control" over making the batter swing at marginal pitches and getting ground balls or popups? It seems FIP ignores that aspect. Is there anything that does?

Warning - I tried doing the DIERA thing but lacked the wherewithal to do the league stats. Found your site via Chris at CapPun.

Harper said...

If the Nats got a full season of FIP equal ERA from the guys you pencilled in the ERA would be somewhere in, what? the 4.50 range? Sad thing is that would still be a half-run improvement from the starters last year.

Lannan is a magic man, Smitty. Don't try to comprehend him.

Paul Brewer said...

Smitty, I used FIP because
a) it is easy to calculate; and
b) it is pretty good at predicting ERA.

You're absolutely right about the absence of the fielding component, and a better alternative would be to do as I did with Wang, and make some projection of the batted-ball results. However, that would have taken me a lot longer.

By showing both the ERA and the FIP projections, I hope that readers can look at someone like Lannan and get an idea of what can be expected. He's an above-average pitcher, but he's probably not quite the ideal #1 guy for a rotation.

DIERA is designed for historical purposes, and really is a work in progress at the moment.