Rating Defense

David Gassko has a nice article on THT today talking about the various defensive rating systems out there including UZR, PMR, ZR, DFTs, and Range. His conclusion is that UZR is the most complete system although no longer published because its creator Michael Lichtman now consults for the Cardinals. He notes that ZR and his own Range statistic compliment each other and PMR also tracks about as well as each of the others indepedantly.

I'll be interested to see how John Dewan's fielding bible will stack up against these other systems.

In many ways these statistics are the cutting edge of baseball performance analysis since they are measuring defense (if you count outfielder throwing) which is the third most impactful part of the game on the field behind offense and pitching. As the state of the art moves forward we're therefore likely to see diminishing returns in the amount of actionable information that is learned through analysis. Behind the big three we then have base running and speed, game strategy, and lineup construction among others.