
How valuable is +/- in basketball?
I've never used it but I instinctively like it (particularly on a per minute basis). Like all stats you need to eliminate the outliers (Burdon's career +/- goes up pretty dramatically when he comes on in garbage time when they are up 20 but how does it go in garbage time when they are down 20?).
Seems to me it reflects a player's contribution to the non-tangibles (or non-stats things) we find hard to track. You boxed out immaculately and set some big screens and as a consequence your team gave up no offensive boards but the ball didn't fall your way and you have a 0 for boards/points in the stats. Yet your team made a 5-point break in that period of play.
Meanwhile, you refuse to box out, crash the offensive boards (without running the offense) and get 4 boards and 4 points during the five minutes, but your team goes down by 5 in that period. I know which player I want playing for me.
I think a focus on this sort of stat ensures players are focused on positive team outcomes rather than individual outcomes (which quite often are unfortunately at odds with each other). Eg, the player at last year's nationals who went after every rebound to ensure she finished in the top rebounders - didn't box out, took some off team-mates (with the occasional spilled ball which went to the other team), achieved her goal, BUT the team finished 8th. Operation successful - the patient died.
This could also be known as the Mugsy Bogues stat. I remember Lute Olsen (after the 90 World's I think) talking about why he took Bogues away. He said at the selection camp, it didn't matter who they put him with, his team won. His stats weren't great, he just won a lot. They ended up putting him with their worst group, and he still won. Nothing that regular stats would show up, but a +/- makes it quite obvious.
I played with a number of perennial All-Stars whose stats were fantastic, but you knew they would never win a championship (and didn't) because nobody made them accountable for the teams outcomes - only their own.
