What do you think they are measuring? Successful passes vs Interceptions?
A negative measure using standard deviations would indicate you are a extremely $#@!ty passer
Yeah it would mean that you are below the mean, ie in the bottom half. It would depend on who the comparisons were against too. For example: if it was done out of a universe of all defenders, the CB would usually have better % percentages.
So when I ran numbers I looked at this figures, all done in standard deviations - I nerded out on this....
-Passing accuracy
-Possession share (player passes vs. total passes), standardizing based on the league as well.
-Dribble share (how many successful drives vs. dribbling of team)
-Take on Rate (Successful dribbles vs. Unsuccessful dribbles)
-Number of Bad Touches
-Number of Bad Touches vs. Bad Touches of Team
-Total Times Dispossessed
-Number of Times Dispossessed vs. Times the Team is Dispossessed. For example Geoffrey Kondogbia per game as a percentage of team dispossessions is 25%! That's absurd.
-Forward vs. Backwards passes. I penalized backpasses a bit.