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Scouting the Young Fielders

Wait, what?  This is "Staturday," not "Wednescout."  Even if you hate Staturdays, you can skip the text and go to the second-to-last paragraph, which contains an important link that I know you'll want to click.

Let me tell you a little something about defensive stats: when it comes to evaluating a player's contributions, they're shaky. You might have already known that.  But the dirty little secret about defensive stats is this: when it comes to judging what a fielder's true fielding skill is, they're almost worthless.  Well, worthless is an exaggeration.  But we have to be very careful when coming to a conclusion about a how good a defender a fielder is. 

And it has nothing to do with how good the defensive metrics we use are.  Why? Regression to the mean.

If you're too lazy to re-read my primer on regression, then I'll give you the Cliff's Notes version: we must always regress to the mean when figuring true player skills, and the amount we regress is based on 1) how much performance data we have and 2) what the spread in skills are among the general MLB population.  This is independent of how good the defensive metric we are using is.

Let's start with the first issue: how much performance data we have for defense.  A full-time shortstop might have 500 opportunties to field a ball in any given year.  A centerfielder might have 400.  Every other fielder will see fewer than that.  Those numbers are smaller than the number of PAs a player gets in a full season.

The difference between the best and worst hitters, over the course of a full season, is something like 100 runs - think Albert Pujols versus Tony Pena.  Imperfect as our defensive metrics are, they give us a pretty decent idea of how many runs the best and worst fielders are worth over the course of a full season.  A guy like Mark Ellis might save 20 runs on defense, and a guy like Manny Ramirez might cost 20 runs.  Let's tack on five runs on either end to get 50, a nice, round number.  The spread in fielding skill is, generally speaking, about half of much as the spread in hitting skill.

So, to recap: smaller sample size than hitting, smaller spread in talent - ergo, more regression to the mean.  Even if you had the perfect defensive metric.

And that's why we need scouts.  But here's the other dirty little secret: you, too, can be a scout.  Why not?  You watch lots of baseball.  So do I.  And if we put our opinions together, we might start getting there.  Two sets of eyes are better than one.  And a thousand sets of eyes are better than two.

And that's what the Fan Scouting Report is all about.  Every year, Tom Tango asks thousands of fun to give their scouting reports by rating fielders in a variety of categories.  Says Tom:

What I would like to do now is tap that pool of talent. I want you to tell me what your eyes see. I want you to tell me how good or bad a fielder is. Go down, and start selecting the team(s) that you watch all the time. For any player that you've seen play in at least 10 games in 2008, I want you to judge his performance in 7 specific fielding categories.

And best of all, for you statophobes:

And, most importantly, do not, absolutely do not, look at any numbers. Don't look at his fielding percentage, range factor, zone rating, UZR, or anything else that someone else is telling you. I just want you to rely on your eyes. You are the scout. I need you to rely completely on your own observations.

Tom's been doing this every year for about five years now, so we're starting to get good historical data.  But if you look at the number of ballots cast for each player, you'll find that the Red Sox and Mariners players get tons of evaluations, and the A's players very few. 

That's embarrassing to me, and it should be to you, considering that we have a group of knowledgeable and dedicated fans right here on AN.  So what are you waiting for?  Submit your evaluations of the A's fielders.  Think Mark Ellis is criminally underrated?  Can't stand to see Jack Cust commune with his glove?  Then say so!

But this is important: be honest in your evaluations.  This isn't a ballot-stuffing contest.  We're not trying to beat Blue-Grey Sky.  This is an attempt to use the collective knowledge of the best-informed baseball fans our there to help us identify fielding skill.

One more thing, speaking of fielding.

Remember this?



F--- you, injuries.  You took my favorite player from me.