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# Fun With Pitcher Projections

Since this is essentially what we're going to be trying to do for the next four months, I might as well get the ball rolling. This one's a pretty simple system, based on elementary statistics, in which I estimate a range of possible 2006 FIP's by assuming that nothing about the pitcher's ability will actually change. By this I mean that I'm treating each pitcher's 2005 strikeout and walk rates as his "true performance level," and then re-calculating his FIP with his rates reduced or increased by one standard deviation.

(For those curious, the standard deviation can be estimated by sqrt(pq/n), where p = probability of something, q = 1-p, and n = the sample size. So, for example, Gil Meche struck out 13% of the batters he faced last year, so p = 0.13, q = 0.87, and stdev = 0.013 (1.3%)).

Hernandez: 2.51-3.30 FIP
Moyer: 4.20-4.69
Pineiro: 4.25-4.76
Meche: 4.78-5.41

Now let's run the projections again, this time assuming that each pitcher's home run rates regress towards the mean (which is that 11% of all outfield flies go for homers):

Hernandez: 2.35-3.15 xFIP
Moyer: 4.40-4.88
Pineiro: 4.11-4.62
Meche: 4.78-5.41

What if we take this a step further and attempt to estimate ERA's? It's a little more hazy, and the FIP numbers will be more reliable, but it's worth a shot. For example, Joel Pineiro's career ERA is 4.11 while his career FIP is 4.18, so we'll knock his estimated range down by 1.7%. Same procedure repeated for all of them except Felix, who we'll just assume for the sake of simplicity stays the same:

Hernandez: 2.35-3.15 ERA