The Limits of Prescience

A thread over at the Washington Nationals Fan Forums pushed back against some of my projections here and raised a few points that I neglected to address in my 2012 projections.

Margins of Error

Interesting projections but the missing piece would be an estimate of how much of a margin of error there would be for both the offensive and defensive estimates that would provide a range for the expected number of wins as opposed to a hard number.

This was a serious omission on my part. All projections have a certain degree of uncertainty built into them, and I really should have discussed the degree of uncertainty built into mine.

I took my method for calculating the projected runs allowed by pitching and defense from this site. The author tested this method against 7 years of complete season data from 2002 through 2008. As he writes:

I found the R^2 value. Not to oversimplify things too much, but this value basically shows what percentage of the variation can be accounted for by the model. The value ranges from 0 (worthless) to 1 (perfect). For my 210 data points, I had an R^2 value of about 0.78 (i.e. 78% of the variation).

That means that my defense and pitching runs allowed projections should be good for plus or minus 22%. That gives a lower bound of 482.84 runs allowed and an upper bound of 755.20 runs allowed.

If we assume that my offensive predictions are correct (a problem I’ll get to in a second), that means the 2012 Nats will win anywhere between 68 and 103 games

I know that’s an immense difference. I’m not sure how I could close that gap. UZR doesn’t account for pitcher or catcher defense, for instance. But even then, I think the method at least gets us in the ballpark.

The offense numbers are a lot more troublesome. I haven’t been able to do any real regression analysis to determine how good my model is–I simply haven’t had the time.

On the other hand our offense has way too many question marks to estimate the total number of runs scored with enough precision to come up with a meaningful value that can be used in a secondary projection as you did in calculating our win total.

Any type of future projection is likely to involve more than a little handwaving. Here, I’ve drawn an arbitrary line: all players included in this analysis are players on the Nats’ 25-man roster as of January 27, 2012, some 23 days before pitchers and catchers are due to report at Viera.

Individual Players and the Projections

Will Werth stay Werthless?

2011 Jayson Werth was astonishingly bad. I’m going to believe that his 2011 numbers are aberrations and not indicative of a “new normal.” I’m fairly confident that the 4-year average from 2008-2011 is a fair picture of what kind of player Werth is now–somewhere between his Philly days and the debacle of 2011.

Will Desmond, Ramos, and Espi improve or stagnate?

As far as Desmond and Espinosa, I have no idea. I don’t think I have nearly enough data about them to make any predictions going forward. Ramos, however, gets a nice bump from more playing time and more PAs. His wRC/PA isn’t terrible, so that’s to be expected.

Will Morse fall back to Earth?

I’m going to go ahead and say No. As I said in Part 3, Morse’s modest offensive outputs in 2008-2010 might make you think that he’s going to crash down to Earth in 2012. But, remember, I’ve taken a four year average of his wRC/PA over the same period. Giving Morse 600 plate appearances in 2012 gives a projected wRC of 97.00: exactly the same as his breakout 2011 “beastmode” year. Indeed, even if we throw out Morse’s 2011 season, running the same calculation over data from 2008-2010 yields a projected wRC of 90.00: Seven runs short of our prior projection and of the 2011 total, but still enough to make him almost as good as Ryan Zimmerman (projected for 90.69 wRC). Indeed, all of this taken together seems like pretty persuasive evidence that “beastmode” has been lurking inside him the whole time, and only needed to see enough PAs.

Will Zimmm get hurt again? Will LaRoche bounce back?

My response: Dammit, Jim, I’m a baseball fan, not a doctor!. I have really no good way of figuring out La Roche’s prognosis post-surgery, nor can I really know anything about the state of Zimmerman’s joints and muscles. The only real response I have here is that the four-year interval I picked should be fair to both men in terms of their expected production.

Who plays centerfield?

Again, I had to draw an arbitrary line and go with who was in the organization as of the day I began compiling the statistics. That means that for now, we’re looking at a DeRosa/Bernadina platoon in center field. This might not be ideal, but I didn’t want to mix players who weren’t officially in the organization into these projections. Blown Save, Win, however, has attempted to address the center field question in a recent post, where he suggests that perhaps the short-term answer is Rick Ankiel. I’ll have to go back and study this, obviously.


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