(11-09-2021, 11:54 AM)mavsluvr Wrote: It tells you absolutely nothing about how that player played.
It tells you how the TEAM (which includes that player) played/performed when that player was on the court. That is the fact it presents. For instance, The Mavs have been severely outscored this year when Luka has played. They have on the other hand the Mavs have handily outscored their opponents when Luka hasn't played. That is the fact which +/- is telling us and it won't and cannot "lie." It is what it is. Our conclusions beyond that are 100% debatable, but with larger sample sizes our confidence in reaching more conclusions will get higher.
But we also have lots of other numbers and observations to add to what +/- is telling us. For instance we see Luka shooting 29.5% from three. We see the team as a whole shooting 26.7% on OPEN threes. So for instance we can safely surmise that Luka's -2.5 offensive on/off is partly (mostly?) from Luka shooting poorly himself AND from his teammates missing so many of the open looks he has gotten them.