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Monday, December 07, 2009
Dual positions
Chris Dial:
The defensive differences is significant enough from position to position, I don’t’ beliee a position adjustment as Tango does it is at all accurate. AT ALL. By his method, ARod would be a +20 defender at 3B, and he’s a -5. That’s not anecdotal - players ability to switch successfully varies wildly, and the data he used to come up with those is extremely limited in innings played.
That would seem to me to be the very definition of anecdotal.
And, I don’t remember saying or suggesting anything about ARod being +20. According to Fangraphs, he was +13 and +11 per 150G at SS. That probably made him a true +10 at SS. Put him at 3B, and he comes in at +15 if he gets the same number of opps. Since 3B get about 80% the opps of SS, that would make him +12. And in 2004, he was.... +12. That’s proof! Actually, that’s anecdotal, too.
I don’t know the definition of “extremely limited in innings played” means. I always report the number, which I will say in english is “pretty g-dd-mn high”. I guess the reader can decide which adjectives are more accurate.
The ONLY issue is the selection bias: only specific players, and specific types of players, are tried in both spots. That’s the only argument that holds water.