White Sox general manager Ken Williams … and his director of baseball operations, Dan Fabian, are interested in some of these new-age stats, too, and UZR, or Ultimate Zone Rating, ranked Chicago as the fourth-worst team defense in the Major Leagues in 2009.
Developed by statistician Mitchel Lichtman, UZR, as described on FanGraphs.com, where the statistics are available for free, quantifies “the number of runs above or below average a fielder is, determined by how the fielder is able to get to balls hit in his vicinity.”
UZR gets to this number by combining “range runs,” which are “the number of runs above or below average a fielder is, determined by how the fielder is able to get to balls hit in his vicinity,” and “error runs,” defined as “the number of runs above or below average a fielder is, determined by the number of errors he makes as compared to an average fielder at that position given the same distribution of balls in play.” Added to standard UZRs are the UZR/150 numbers, or “the number of runs above or below average a fielder is, per 150 defensive games.” …
“Don’t use UZR/150 … if at all possible. It’s way too misleading.”
