A Substitute for War

Basketball philosophy

Gasol, Bosh, and +/- Statistics

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I’m getting a lot of Heat for continuing to have Pau Gasol ahead of Kobe Bryant in my POY/MVP rankings now that Gasol is clearly in an extended slump.  There are multiple factors involved in my decision making process, but something I haven’t heard any one deal with regarding this debate are the +/- statistics.

For those unfamiliar, +/- statistics rate players based on how well their team does when they are on the court compared to when they are off the court.  It was invented in raw form in hockey, but it’s basketball that has really gotten sophisticated with it.  The great thing about +/- stats is that they literally catch everything relevant that happens on the court.  That great screen a guy set that let to the open shot?  Counts.  That great pass before the pass that got the assist (aka the hockey assist, so named because they actually give that guy an assist in hockey)?  Counts.  Box score based stats are forever at the mercy of what scorekeepers do and don’t track.  The gambling thief who keeps trying and failing to get and assist, leading to the opponent getting an easy buck is doing nothing wrong according to traditional box score stats, but +/- stats catch what he’s doing.

Of course there are weaknesses to the stat as well.  First, the very fact that it catches everything when we don’t have box score stats for everything means that it’s advantage in coverage is a disadvantage in explanation.  This opens the door for skeptics to say that any number of factors could be involved in stat’s results, and they’ve got a point.  If a stat says I did something good just by being on the court when my team’s star gets into a zone, that stat is certainly not perfect.  Second, +/- stats tend to be noisier than traditional box score stats.  The guy who scored 30 points efficiently in a game can be said with almost complete confidence to have had a great game.  You can’t say a guy had a great game simply because +/- said he did well, and when we get into the most sophisticated +/- stats, statisticians strongly prefer to use 2 or more years as the sample size.

Also, related to the “black box” aspect of these stats, is the fact that if you point to them without giving an explanation for the cause of the results, you’re admitting that you don’t really know what’s going on.  This is something that bothers everyone.  It’s hard to stick your neck out there just based on a possibly unexplainable number.  It’s easy to chafe against something that essentially calls your understanding of the game into question.

So, this year, Pau Gasol’s raw +/- (how much the Lakers have outscored opponent’s while he’s on the floor) is +265, while Kobe Bryant is only +148.  Every more advanced metric we have along these lines says the same thing – the Lakers are more dependent on Gasol this year than Kobe, and this is not something we’ve seen in previous year.

Also of note, Gasol’s raw +/- is 2nd in the league.  Who is first?  The often mocked Chris Bosh who is well ahead of his more respected teammates LeBron James and Dwyane Wade.

People who aren’t sold on these stats use this as ammunition against the stats, “See, it’s meaningless I tell you!”.  I can’t help but marvel though and how those numbers actually fit with other things people are saying.

The Lakers, everyone agrees, lack depth at big man.  Bynum’s been injured.  They signed an old Theo Ratliff out of desperation.  They’ve just yesterday traded for an old Joe Smith out of desperation.  Do we really think it’s a coincidence that when the Lakers are desperate for big man, the team appears to be extremely dependent on their star big man (Gasol), who just happens to be playing by far the most minutes of any of their players?

The Heat, everyone agrees, have 2 superstar perimeter players capable of being elite scoring option and offensive decision makers who have had some trouble blending their talents together.  We also know that the Heat are struggling to find quality big men.  Do we really think it’s a coincidence that the guy who the team falls off when he’s not on the court, is the quality big man they do have?

Now if you want to make the argument that there should be more to accolades than a statistic that can be so shaped by the depth of the team the player plays on, I think that’s a perfectly reasonable point to make.  I do think though, that it’s unreasonable to dismiss what +/- stats have to say here.

Written by Matt Johnson

December 15, 2010 at 11:23 am

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