The Big Fundamental Outlier and the NBA at the Twenty Percent Mark

Posted on November 30, 2008 by


On Saturday night the NBA completed 20% of the regular season.  Teams have now played 246 regular season games.  Just 984 more games and the 2009 playoffs can begin. Although the NBA still has 80% of the regular season to complete, I think we can now start to form some ideas about how this season will end.  And those ideas start with Table One.

Table One: NBA Efficiency Differential After 20% of the 2008-09 Season

Table One reports each team’s Efficiency Differential (offensive efficiency minus defensive efficiency) at the 20% mark.  In addition, for each team I have projected the final winning percentage the team’s efficiency differential suggests.

The Struggling Spurs

Before we go over the numbers it’s important to note that no effort has been made to adjust for injuries.  For example, currently the San Antonio Spurs have the 9th best differential in the Western Conference.  Given this result, the Spurs are right now looking at the lottery, not the post-season. 

But the Spurs have played most of the season without Tony Parker or Manu Ginobili.  And since these two players have been very important to this team’s past success, it’s not surprising the Spurs have struggled without each of these players in the line-up.  For the rest of the season, though, Parker and Ginobili – if they stay healthy – will play.  So San Antonio will probably win more than 43 games this season and fans of this team can expect to see playoff basketball.

The Spurs early struggles, though, have led me to wonder about the perception of Tim Duncan.  Since Jordan left the Bulls in 1998, people have debated the identity of the best player in the game.  One player that has to be part of this discussion is Tim Duncan.  Across the past ten seasons, the Big Fundamental has consistently been the leading scorer on a team that has won four championships.

Duncan, though, didn’t win these titles by himself.  Yes Duncan is very productive, but his teammates matter.  The initial 20% of this the 2008-09 season tells us that if Duncan was forced to play with the cast of players employed by the Spurs this year, Duncan would not have hoisted those championship trophies.  And if Duncan was not on four championship teams, would he still be considered an all-time great?

For an answer, consider the career of Kevin Garnett before he arrived in Boston.  As I have noted in the past, Garnett has offered just a bit more than Duncan.  But KG was consistently playing with less talented players in Minnesota.  Consequently, many people believe Duncan has consistently been the better player.

The story of Duncan and Garnett appears to be quite consistent with the argument Malcolm Gladwell offers in Outliers.   As I noted in my last post, “in this book Gladwell examines the source of a person’s success.  We tend to think that an individual’s success is all about the individual.  But Gladwell argues convincingly that success is often about a person’s particular circumstance.”  Applying this argument to Garnett and Duncan… it appears our perceptions of a person’s abilities depend upon the people around the person. 

By the way – again, just as I noted in my last post — I was hoping to post a complete review of Gladwell’s latest, but I have not had the time.  I did read the book and thought it was his best so far.  For a review that appears to be consistent with my assessment, I recommend what David Leonhardt had to say in the New York Times.

Other Stories at the 20% Mark

Beyond the struggling Spurs, what else have we learned at this point in the 2008-09 season?  Here are a few quick observations:

  • The Lakers are the best team in the NBA. And if their efficiency differential holds up (not saying it will, just saying if), the Lakers in 2008-09 will be the best team in NBA history.
  • The Cleveland Cavaliers have improved the most since last season. As I noted a few days ago, this is primarily because Ben Wallace, Anderson Varejao, and Delonte West have returned to form.
  • The Celtics have slipped. Yes, they are still very good. But the team is not what it was last year. And after a quick glance at the numbers, I think we can blame the aforementioned Garnett. KG’s WP48 [Wins Produced per 48 minutes] is only 0.200 this season. This is still far above average, but not nearly the level of productivity Garnett offered in the past.
  • The Pistons have really slipped and are on pace to suffer the biggest decline. I am afraid this change can be tied to the loss of Chauncey Billups and the acquisition of Allen Iverson. Yes, once again, “the Answer” is really not the answer.
  • The Houston Rockets and Toronto Raptors both made major acquisitions in the off-season. In both cases, these moves were made so that these franchises could seriously contend in their respective conferences. So far, though, both teams are posting an efficiency differential that is less than the differential observed last season. So it appears that Ron Artest (in Houston) and Jermaine O’Neal (in Toronto) have something in common with Iverson. None of these players appear to be the answer.
  • The three best teams in the NBA are the Lakers, Cavaliers, and Celtics. At number four we have the Orlando Magic. Dwight Howard is having an amazing season, and the return of Tony Battie has also helped.
  • And the fifth best team is the Portland Trail Blazers. Although I have not looked at all rookies, Greg Oden and Rudy Fernandez look to be on pace to be the primary contenders for Most Productive Rookie award. Currently Fernandez has produced more wins. Oden, though, has the higher WP48 and should eventually have a higher Wins Produced (if he stays healthy). I should note that Oden’s productivity has been obscured by the outstanding play of Joel Przybilla. And I should also note that Portland employs six players with WP48 marks that are above average. None of these, though, are named LaMarcus Aldridge

Those are just a few stories in this season.  It’s important to remember that most of the season remains to be played.  That being said, I would be surprised if the identity of the top teams – and the teams at the very bottom – is going to change much as the season progresses.  Yes, it’s beginning to look like LeBron vs. Kobe could be the story next June.

– DJ

The WoW Journal Comments Policy

Our research on the NBA was summarized HERE.

The Technical Notes at provides substantially more information on the published research behind Wins Produced and Win Score

Wins Produced, Win Score, and PAWSmin are also discussed in the following posts:

Simple Models of Player Performance

Wins Produced vs. Win Score

What Wins Produced Says and What It Does Not Say

Introducing PAWSmin — and a Defense of Box Score Statistics

Finally, A Guide to Evaluating Models contains useful hints on how to interpret and evaluate statistical models.