20090918

"I can see for miles..."

A lot of SABRmetrics, it seems to me, is trying to provide an easy answer to the question of, "How good is this player?"

And most of it is trying to do so with a number (OPS, OPS+, wOBA, VORP, UZR/150, ERA, ERA+, FIP, xFIP, tRA, WPA/LI, WSAB, WAR, etc). But Beyond the Boxscore's Justin Bopp just came up with a different way. In a very good decision, they decided to do it graphically.

It attempts to give you a "diamond's eye view" of a player's contributions on offense, defense, and on the bases.

It's a very cool idea, although I think the implementation might need a bit of work. Take a look at Adam Dunn's graph in the article. While it looks very cool, I think it shows a potential problem. To wit, if a player has a sufficiently negative fielding value, and sufficiently small slugging, they would end up with a negative area. And while that would look pretty neat, I don't think anyone would argue that it isn't too useful. (The easy way to fix this, of course, is to set the middle (50% at 0 UZR/150, and set the extremes at +/- the largest absolute value UZR/150 in the league.)

But that does lead to a neat idea. If it could be weighted appropriately, it would be really neat if we could look at that, and the area within the polygon bounded by the player's four values would give a good proxy for a player's overall value. To do that, of course, the four quadrants wouldn't be equal (on base would be significantly larger than slugging, for instance). Taking it one step further, making it a really neat overview would be to find a way to make the area within the boundary equal (in some sense) to, say, WAR.

Of course, maybe that would defeat the purpose of the exercise. If the purpose is to see how someone's component skills compared to the rest of the league at a glance, then that might not work. That is, the baserunning component would be so small as to be impossible to make comparisons, most likely. But it would still be cool.

One minor quibble with the overall method (about which I don't have any idea how to deal, at the moment), is that someone's values can change from one day to the next, even if they didn't play on a given day.

Glove slaps: tango, neyer.

Update: I forgot that I wanted to mention: did Pujol's defense rating end up so low because of positional adjustment? I expected his to be much higher.

I'd also be curious to know what Nyjer Morgan's graph would look like.

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