You may have noticed in the last four years the use of Statcast on MLB broadcasts. Statcast is a system that can track everything that happens on the field from spin rates of baseballs, to launch angles of batted balls, to where players are positioned, to where the ball ended up. Statcast started measuring all MLB games in 2015 using a Trackman Radar system coupled with an Optical Camera.
Just this week, Statcast came out with a new metric IOAA (Infield Outs Above Average). Similar to Outs Above Average, that came out a few years ago for outfielders, it compares each play a defender makes or doesn’t make to every similar play that has come before it.