One well-known statistic the Rockets’ front office pays attention to is plus-minus, which simply measures what happens to the score when any given player is on the court. In its crude form, plus-minus is hardly perfect: a player who finds himself on the same team with the world’s four best basketball players, and who plays only when they do, will have a plus-minus that looks pretty good, even if it says little about his play. Morey says that he and his staff can adjust for these potential distortions — though he is coy about how they do it — and render plus-minus a useful measure of a player’s effect on a basketball game. A good player might be a plus 3 — that is, his team averages 3 points more per game than its opponent when he is on the floor. In his best season, the superstar point guard Steve Nash was a plus 14.5. At the time of the Lakers game, Battier was a plus 10, which put him in the company of Dwight Howard and Kevin Garnett, both perennial All-Stars. For his career he’s a plus 6. "Plus 6 is enormous," Morey says. "It’s the difference between 41 wins and 60 wins." He names a few other players who were a plus 6 last season: Vince Carter, Carmelo Anthony, Tracy McGrady.

I’m curious how they do this

Basketball is not discrete sport of similar instances (like baseball and to a large degree football) but 10 players interacting in enormously complex ways.

If the Rockets have a stat that shows T-Mac, Air Canada and ‘Melo are the difference between an average team and an elite one I’d have to tell them to go back to the drawing board.

Thanks, Cheat. Great article.