Improving the Twins

[jimmer]

 

It's more than that.  It's balls-hit-that-direction-that-resulted-in-outs.  So it's FP% plus zone defense plus catching baserunners, with double plays and fielder's choices thrown in for fun.  

 

Though the specific formula for UZR is secret knowledge (do you know the formula?), I strongly suspect F2O% is a factor.  This means it's factored into fWAR as well.  The zdefense guy is using it and getting similar numbers to UZR.  

z-defense (the overall stat that combines z-outs, z-range and z-fielding) tries to factor in all those things, F20% doesn't.  F20%, by itself, doesn't even use range.  it's Field to out, period.  It is supposed to be combined with RZR.

 

http://www.fangraphs.com/community/a-zdefense-primer/

 

The guy who created z-defense is trying to create his own version of UZR with some different components mixed in.  If he used exactly the same as UZR, what would be the point? :-)