## Wednesday, November 17, 2004 |

## Treating Junk Stat Pollution

*Future Angels*, has charged after a windmill that never needed knocking down, namely, the idea that OBP corresponds to runs scored. He gives it quite a try, but in the end, fails to prove that which he set out to do. He observes that offensive efficiency could be measured by the number of plate appearances divided by the number of runs scored. Ideally, of course, all your players would hit home runs each time they got to the plate, so the best case is unity, but the worst case -- impossible to occur in the real world -- is infinity (no runs scored but some non-zero number of plate appearances). Smith doesn't do any correlation analysis on his efficiency rating, so I thought I would do it for him. I start in 1930 -- an arbitrary cutoff, to be sure, but I didn't want to spend the rest of my night crawling MLB.com, not to mention there are some major rule changes that occurred around that time (such as the end of calling the modern ground rule double a home run). Here's some correlation figures between three different statistics and runs scored:

Stat r ============= OBP .800 Avg .735 TPA/R -.115

*negative*correlation -- as we would expect, considering a

*good*team should theoretically have a lower ratio than a bad team -- but an extremely weak one. (A good correlation can still be negative; the closer to zero it is, either way, the less useful it is.) And this isn't even doing park or league adjustments.

Smith later brings up dat ol' debbil Productive Outs, introduced earlier this year in a Buster Olney ESPN column, to back up his claims. I won't bother flaying the value of this statistic, as it's already been ably done by Larry Mahnken at *Hardball Times*. Mahnken's comment about Productive Outs seems equally apropos of Smith's treatment of the subject, namely, that "making productive outs is not an important part of winning ballgames" and that nobody -- neither Olney nor Smith -- have shown otherwise. If indeed this is what the Angels are teaching their prospects in the minors, the club is systematically wrecking the careers of the "waves of talent" from a farm system David Cameron labeled "the best in the game".

**Update:** Apparently the boys over at *Baseball Think Factory* have glommed onto this. Some good reading there; one reader asserts Smith's strikeout calculations are wrong, and also notices that

David Pinto also shares his thoughts:Simply looking at who scored the most runs is misleading, because one team could have sent many more players to the plate than the other. So let's find a common denominator.But's that's exactly it! High OBP teams strive to send more players to the plate because they makes outs at a slower rate! The ratio of runs to plate appearances is irrelevant.Since he missed this obvious fact at the beginning, the rest of the column is dangles on a broken branch.

The point of Mr. Smith's article is one Bill James made 20 years ago. Given two teams with the same OBA, the team with the higher batting average will have the better offense. Hits are simply more valuable than walks in advancing baserunners.

**Comments:**

*we have no historical data*. The statistic comes from the Elias Sports Bureau, and they don't seem to be getting us data before this year (last time I looked at ESPN, anyway). But like I said, I'm not here to talk about the POP stat; the Mahnken article at

*Hardball Times*pretty much assails that one adequately.

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