It looks like MLBAM will release the defensive tracking system this year, although it will only be rolled out in a few ballparks. There’s a good video at the link of how it works, plus a route map.

If you take a look at the map, it shows something that I learned from the Probabilistic Model of Range (PMR) studies. The outfielders don’t overlap that much. One criticism of my model was that it dinged players who didn’t catch a ball on plays where someone was going to make the play anyway. For outfielders, at least, it’s not really a problem.

What I really love about the availability of this data is that we will finally be able to separate range from positioning. The definition of range that I’ve worked with over the years is one that comes from the Bill James Abstracts, the ability to make a play. Under that definition, a player can show great range either by being able to move a long distance to field a ball, or by positioning himself well so he doesn’t need to move a long distance. With this tracking data, we will actually know who moves a long distance, and who put himself in the right position. I’m actually somewhat interested in players who have great range, but poor positioning. I’d love to see if those are the player who turn out to look good but score poorly in the probabilistic studies.