Revised: The standard deviations were off a little bit, though it doesn't change the proportion of adjusted UZR/150 values among different positions. (Apr 22, 2010 3:00 PM EDT)
Not much progress yet with the Sabermetric DiamondView Composite graphic, but I did come up with a useful new stat sabermetricians would crave for - adjusted UZR/150. This accounts for the differing UZR/150 rates, due to player position. Please keep in mind that the adjusted stats are for relative defense (based on position) - not overall defense. This information is based on a compilation of ALL the yearly UZR/150 data that was obtainable through Fangraphs, for eligible players.
Keep in mind that Catchers do not have UZR/150 ratings, so any attempt to gauge their defense would be inaccurate. That one is going to be difficult to rectify. Some rSB/150 stat would have to be created for them, which is not currently available.
Let x = UZR/150
Format: (x - positional mean) • adjustment factor
The "adjustment factor" is based on the average standard deviation of UZR/150 rates by position.
1B: (x - 0.70) • 1.39
2B: (x - 1.00) • 1.21
SS: (x - 0.75) • 1.16
3B: (x - 2.15) • 0.97
RF: (x + 0.85) • 0.81
CF: (x - 2.00) • 0.90
LF: (x + 1.75) • 0.83
Since 2002, Ryan Braun had the absolute worst defense, relatively speaking, when he played 3B in 2007, so it made sense that the Brewers moved him to the outfield. Alfonso Soriano, on the other hand, had the absolute best defense, relatively speaking, when he played LF for the Cubs in 2007 - he flashed some sick leather that year and the year after that, before taking a steep nosedive in 2009.
Let's use this in a practical situation. Who had better defense for their position last year?
A) Mike Cameron (CF), with an 11.0 UZR/150
B) Justin Morneau (1B), with a 6.7 UZR/150?
I will skip the math and all, but when it comes down to it, here are the results, rounded to the nearest tenths:
8.3 Justin Morneau
8.1 Mike Cameron
It's not a big difference, but nevertheless, Justin Morneau's defense had a higher value at his position than Mike Cameron's defense did at his, though Cameron edged him out decisively in the UZR/150 category, by 4.3.