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Old 05-16-2013, 02:26 PM   #12
VanillaGorilla
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Quote:
Originally Posted by David Watts View Post
This stuff is all way above my head, but could Torrez be getting a bump due to his years pitching in Boston?
It is the opposite. Torrez gets his numbers knocked down from the Boston years because there is not a park adjustment for the base stats.

Any neutralization effort will have a systemic bias, including the one in use on BBREF (based on Bill James work) and it is this neutralization process that OOTP uses, in part.

I say "in part" because for the historical neutralization the part of the formula that adjusts for the home ball park is simply left out.

I performed the same check for the OPS leaders in my current league that I did for the ERA leaders. 20 of the top 23 places (I only checked through 23...what number 24 is, I don't know) had neutralized slash lines in OOTP better than on BBREF. Reggie Jackson's slash for the neutralized data was exactly the same across the board (the universe revolves around Reggie???).

I will post more on this later. There appears to be a discrepancy in how hitters and pitchers are, respectively, neutralized, also.

One thing is clear: the neutralized data that is used for historical players (pre 2009...more on this later, also) is NOT adjusted for the actual home park the player pitched/batted in, and this is leading to biased results which favors hitters from hitting parks and pitchers from pitching parks.
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