Thursday, June 19, 2008

A realization and another piggyback

I keep meaning to do something worthwhile in this space, to explore some area of baseball research that I'm curious about or to develop some new way of thinking about a problem. In reality though, that stuff is far more involved than I'm usually willing to commit to, so I end up piggybacking off of other people's blogs, which essentially makes me like every other blog on the Internet (not that there's anything wrong with that).

Today's piggyback is from Rob Neyer, who is unfortunately behind the ESPN Insider curtain:
The "anti-scout stat geek"? He's a straw man. Doesn't really exist, at least not in any meaningful numbers. As for scouts doing "a better job of projecting prospects than the numbers do" … Well, we don't really know that, do we? When scouts evaluate players, even Class A players, they can't help but notice the numbers. And when number geeks evaluate players, they read the scouting reports.
This is a marvelous point and it points out a flaw on both the objective and subjective realms of baseball analysis.

Not only are scouts, the subjective analysts, not impervious to the influence of numbers (after all, they have to use some data to back up a projection, even if it's height, weight, age, bat speed, fastball velocity, or whatever), but they are not forced to quantify their projections into any meaningful set of numbers. Thus, unlike purely objective projection mechanisms, it's really hard to evaluate how well they've done at projection. If I were paying scouts, I'd have them rigorously quantify their projections along the lines of providing basic stat lines at various percentiles for important ages at the major league level. Then you would be able to actually grade how well your scouts do project and give them valuable feedback.

Of course, Rob exposes a problem on the objective side as well. Objective analysts too often fool themselves into adding their own subjective point of view to a supposedly objective evaluation. It drives me crazy every time I see Nate Silver hedge his PECOTA projections. Which is it, Nate? Are your PECOTA projections "deadly accurate" or do they need subjective adjustment? It completely defeats the purpose of objective analysis when the analyst starts adding his own view point.*

* Yes, I realize that BPro articles are for entertainment first, and they do entertain me, but I still reserve the right to get annoyed. I'm sure Mr. Silver understands my point without needing a correction from yours truly.

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