David Pinto's Probabilistic Model of Range has been receiving some attention around the blogosphere and on Baseball Primer. It's a somewhat complicated but interesting attempt at attaining sabermetrics holy grail: accurately measuring defense.
Using data from Baseball Information Solutions (truth in advertising: his employer) David uses batted ball types (a combination of trajectory, angle, and velocity), calculates the probability of those types of batted balls being turned into outs or non-outs, and compares how teams and players actually performed in comparison to how they should have done, given the probability of an out or non-out. In other words, given the batted ball types and the probability that they should be fielded, did Player X (or Team Y) exceed expectations? In David's own words, "A negative number means the team performed below expectations. A positive number means they exceeded expectations."
So far, David has rolled out his ratings for all the teams in baseball, plus shortstops and second basemen, and the reports are good for Phillies fans. The team as a whole ranked fifth in all of major league baseball and third in the National League. And the good news continues as the Phillies Most Likely Middle Infielders in 2005 -- Placido Polanco, Chase Utley, and Jimmy Rollins -- ranked highly at their respective positions. Untouchable Utley ranked first and Polanco ranked seventh among all second basemen. Polanco's ranking is no surprise, but for Utley to finish first certainly contradicts conventional wisdom. Jimmy Rollins, while turning fewer outs than would be mathematically expected, still managed to rank eighth in all of baseball among shortstops.
I think the Phillies are correct in putting together a heavy groundball-inducing pitching staff, but for that strategy to be truly successful, the Phillies are going to need good infielders, particularly middle infielders. According to these measures, they've achieved that portion of the strategy. While the extent of the validity of all measures of defensive ability remain in question, this should still be very comforting news to phans.
Or at least those phans that are comforted by this kind of thing.
