Originally Posted by texasdave
The way I understand UZR ratings, this is not entirely true. They do look at the percentage of balls hit into a zone by a player. But that number is then compared with the percentage of balls that all outfielders catch in that particular zone.
A quick example with entirely made up numbers for illustration purposes. Say in GAPB Drew Stubbs catches 85% of the balls in his zone. However, of all the balls hit into that zone, 90% are caught. That makes Stubbs a below average fielder. Next, say Fowler only catches 80% of the balls in his bigger- zone in Colorado. But, at the same time, of all the ball hit into that zone only 75% are caught. That would make Fowler an above-average fielder. By doing it this way the size of each zone is irrelevant. At least that is how I understand the workings of UZR. I could be wrong.
You are correct. There is some element of a park factor built into UZR, but even then, the anecdotal evidence shows defensive metrics are historically harsh to Colorado OFers. Even good ones.