Underrated Statistics and Underrated Players

Posted on August 13, 2010 by


Zenon Zygmont – one of the co-authors of The Economics of Intercollegiate Sports – alerted me this morning to the following from Tyler Cowen of Marginal Revolution

Very Difficult Questions: I have spoken at Jane St. Capital a few times and it is perhaps my favorite audience; everyone wants analytic content and everyone came prepared.  All of the questions were tough, but two in particular I was not prepared for.

First, I was asked “Which is the most underrated statistic for judging the value of an NBA player?”

My attempted answer was the player’s presence on a very good, consistently winning team.  There are many players with impressive statistics, including unselfish statistics such as assists and rebounds, who are only of value on bad teams.  We overvalue such players.  Overall, really good teams don’t keep bad players and really bad teams don’t keep good players.  If a player has never been on a really good team, he might not be so good, with apologies to the earlier Kevin Garnett.

Tyler’s response is —-hmmm…. okay, rather than comment on the quality of this response, let me just offer some thoughts.

Player statistics are tracked to separate a player from his teammates.  This is necessary because we can see which teams are successful.  What decision-makers need to do is determine which players were responsible for the team outcomes observed.

When we look at player evaluations in the NBA (i.e. salaries paid to free agents, the allocation of minutes, where a player is selected in the NBA draft, and various NBA awards) we see that scoring totals dominate the decision.  Factors like shooting efficiency, rebounds, and turnovers are not consistently found to matter.

Such a story has been told before (see The Wages of Wins, Stumbling on Wins, or just this post on Carmelo Anthony).  And this story indicates that scoring totals are overvalued, and shooting efficiency and factors associated with gaining and keeping possession of the ball (rebounds, steals, and turnovers) are undervalued.

Once the statistics are valued in terms of wins, we do discover players on bad teams who are good.  For example, here are the top 10 producers of wins on losing teams from the 2009-10 season (a similar list – with some of the same names – can be produced for other seasons):

  • David Lee, New York Knicks: 15.5 Wins Produced
  • Andre Iguodala, Philadelphia 76ers: 14.4 Wins Produced
  • Troy Murphy, Indiana Pacers: 14.4 Wins Produced
  • Zach Randolph, Memphis Grizzlies: 14.3 Wins Produced
  • Kevin Love, Minnesota Timberwolves: 12.1 Wins Produced
  • Chris Bosh, Toronto Raptors: 11.7 Wins Produced
  • Chris Paul, New Orleans Hornets: 11.5 Wins Produced
  • Samuel Dalembert, Philadelphia 76ers: 10.6 Wins Produced
  • Ben Wallace, Detroit Pistons: 9.9 Wins Produced
  • Marc Gasol, Memphis Grizzlies: 9.1 Wins Produced

And to be balanced, here are the top ten least productive players (minimum 2,000 minutes played) on winning teams in 2009-10:

  • Derek Fisher, LA Lakers: -0.2 Wins Produced
  • Rashard Lewis, Orlando Magic: 0.1 Wins Produced
  • Jeff Green, Oklahoma City Thunder: 1.o Wins Produced
  • Boris Diaw, Charlotte Bobcats: 1.1 Wins Produced
  • Channing Frye, Phoenix Suns: 1.3 Wins Produced
  • Mehmet Okur, Utah Jazz: 2.0 Wins Produced
  • Michael Beasley, Miami Heat: 2.2 Wins Produced
  • Aaron Brooks, Houston Rockets: 2.5 Wins Produced
  • Martell Webster, Portland Trail Blazers: 2.7 Wins Produced
  • J.R. Smith, Denver Nuggets: 2.8 Wins Produced

One should note, the Minnesota Timberwolves have acquired two of the players on this latter list.  And with players who “know” about winning, we can expect Minnesota to get much better.

Okay, that probably isn’t going to happen. Yes, the T-Wolves have Kevin Love. But beyond Love, the cupboard in Minnesota is essentially bare.  After all, this is a team that seems committed to giving Darko Milicic significant playing time.  

Now let’s imagine that Love keeps producing but the T-wolves keep acquiring unproductive players and unnecessary point guards.  What should we conclude about Love if this continues for five or six more years?  One might be tempted to argue that if Love keeps playing for losers that he is a bad player. But I think the stats – just as they did with Kevin Garnett when he was employed by Minnesota – would tell a very different story.  Again, stats are supposed to separate a player from his teammates.   And when we make this separation, we do discover that good players can be found on persistent losers.   In other words, team outcomes are really not an underrated stat.

– DJ

P.S. Not sure anyone noticed, but I was gone for much of this week (as in, away from the Internet).  Hence there were no posts after my comment on Carmelo Anthony on Monday.  While I was away there was some stuff happening in the NBA.  Hopefully I can post some comments on this stuff this weekend (or at least link to the brilliant stuff written by other people).