Supporting Casts are More Important Than Stars

A while back I used 2002-2012 PI RAPM data to quantify differences in the “supporting casts” that surround a star player. The results were largely what we’d expect: That the players who surround a star (including other all-stars themselves) are hugely important in determining a team’s performance.

In the chart below I’ve graphed a team’s best player and his support based on how far they advanced in a season. I’ve also included min/max ranges for the supporting casts based on the data:

The data reflects common sense. As teams grow better, the players surrounding the star grow better. Improvements to the star himself are correlated with more team success, but the supporting players on a team are more important to the team’s success than the star player. This is expected; basketball is not a one-on-one sport. Still, it’s nice to be able to quantify this with a decade of non-box score data.

The importance of supporting casts can be seen most clearly in the correlations. The correlation between the entire team’s individual RAPM values and its Margin of Victory (MOV) is nearly perfect (0.95). The correlation between the “supporting cast’s” RAPM and MOV is 0.91, but the correlation with a best player’s RAPM is only 0.68. So if we removed the star player from every team in the league, we could still reasonably predict who the best teams were based on the performance of the other players. We could not make this prediction by only looking at the stars themselves.

Graphically, we can see the relative lack of relationship between the top player and team MOV compared to the strong relationship between the supporting players and team MOV:

Finally, note the vast disparity in supporting cast among non-playoff teams. The floor for a playoff team and the floor for a non-playoff team are separated by 10 points! Literally, off the chart.

Methodology

  • “Best Player” is defined by the player with best minute-weighted RAPM for a team for a season. For example, if Player A has +5 RAPM and Player B a +4 RAPM but Player B plays 100% of the minutes and Player A 50% of the team minutes, Player B is credited with a “4” lift to the team and is thus considered their best player. (B would have a +2.5 lift).
  • “Supporting Cast” is defined by the minute-weighted totals of all other players on the team, summed together.
  • For traded players, the total season RAPM value was used
  • For minute-weighted totals, only players with 300 MP were considered

Specific Players

I’m always asked for notable players across a period, so this is how they shook out based on this metric. First players with at least 3 seasons as the “top player.” The second table has all players.

PlayerAvg.MinMax200203040506070809101112
Dirk Nowitzki1.0-2.23.50.13.10.22.51.23.50.40.80.4-2.2
Kevin Garnett-0.4-7.85.30.1-0.6-0.2-1.0-5.2-7.83.95.32.2-1.0
Tim Duncan2.40.73.43.43.02.71.82.70.72.02.03.2
LeBron James0.1-4.03.00.9-1.8-1.7-4.02.6-0.43.02.4
Luol Deng-0.3-4.54.3-1.1-1.61.5-4.5-2.92.54.3
Steve Nash-0.1-3.54.20.24.20.6-0.81.8-3.5-3.0
Baron Davis-1.7-3.00.9-0.50.9-3.0-2.7-2.6-2.0
Dwight Howard-0.1-4.53.7-4.5-1.52.23.70.4-1.0
Elton Brand-2.2-4.8-0.3-3.8-0.3-1.1-2.2-4.8-0.9
Jason Kidd0.3-2.53.32.43.3-0.2-1.5-2.50.1
Kobe Bryant-0.1-3.74.5-2.7-1.7-3.71.34.51.6
Brad Miller-3.2-8.30.00.0-1.2-2.3-4.2-8.3
Dwyane Wade-4.5-9.6-0.9-0.9-3.6-9.6-4.0-4.5
LaMarcus Aldridge-0.4-2.92.6-2.92.60.4-0.5-1.5
Rasheed Wallace0.1-1.42.6-0.40.9-1.42.6-1.1
Andrei Kirilenko-1.1-6.42.8-1.9-6.42.81.2
Chris Bosh-2.6-3.8-1.6-1.8-1.6-3.8-3.2
Chris Paul-2.5-3.6-0.5-2.7-3.3-3.6-0.5
Gerald Wallace-3.9-6.6-0.3-6.2-2.4-0.3-6.6
Josh Smith-2.7-7.21.2-7.21.2-2.9-1.8
Paul Pierce-3.0-5.4-1.5-1.7-1.5-3.6-5.4
Ray Allen-1.8-6.02.6-5.01.1-6.02.6
Shaquille O'Neal1.4-0.13.21.41.0-0.13.2
Shawn Marion-0.9-3.11.8-3.10.5-3.01.8
Steve Francis-2.3-4.7-1.0-4.7-1.2-1.0-2.4
Allen Iverson-1.7-3.9-0.4-0.9-3.9-0.4
Andrew Bogut-2.7-3.4-2.2-2.2-2.3-3.4
Antawn Jamison-4.4-7.2-1.3-1.3-4.6-7.2
Ben Wallace-2.0-6.43.0-2.43.0-6.4
Bobby Simmons-5.4-9.2-3.0-4.1-3.0-9.2
Brendan Haywood-4.9-6.8-1.7-6.8-1.7-6.2
Carlos Boozer-0.4-1.72.3-1.7-1.62.3
Chauncey Billups3.02.53.72.73.72.5
Danny Granger-2.3-5.4-0.1-1.5-5.4-0.1
Jermaine O'Neal-1.2-4.01.7-1.21.7-4.0
Kevin Durant1.60.14.00.10.84.0
Marcus Camby-5.9-9.6-0.9-0.9-9.6-7.2
Metta World Peace-2.9-6.41.1-6.41.1-3.5
Nene Hilario0.5-1.51.9-1.51.91.1
Pau Gasol-1.1-8.14.1-8.14.10.7
Rashard Lewis-2.8-8.63.7-3.53.7-8.6
Shane Battier-0.2-1.30.90.9-0.3-1.3
Theo Ratliff-6.6-9.7-4.1-4.1-6.0-9.7
Vince Carter-7.2-7.2-7.1-7.2-7.2-7.1
PlayerAvg.MinMax200203040506070809101112
Al Harrington-2.5-2.5-2.5-2.5
Allen Iverson-1.7-3.9-0.4-0.9-3.9-0.4
Alvin Williams0.80.80.80.8
Amir Johnson-6.4-8.5-4.3-8.5-4.3
Anderson Varejao-7-7-7-7
Andre Iguodala-2.3-2.3-2.3-2.3
Andre Miller-0.4-1.91.11.1-1.9
Andrei Kirilenko-1.1-6.42.8-1.9-6.42.81.2
Andrew Bogut-2.7-3.4-2.2-2.2-2.3-3.4
Andrew DeClercq-5.9-8.5-3.2-3.2-8.5
Antawn Jamison-4.4-7.2-1.3-1.3-4.6-7.2
Anthony Morrow-8.6-8.6-8.6-8.6
Anthony Parker-11.1-11.1-11.1-11.1
Anthony Tolliver-8.2-8.2-8.2-8.2
Antoine Walker0.70.70.70.7
Baron Davis-1.7-30.9-0.50.9-3-2.7-2.6-2
Ben Wallace-2-6.43-2.43-6.4
Beno Udrih-2.4-2.4-2.4-2.4
Bob Sura-4-4-4-4
Bobby Simmons-5.4-9.2-3-4.1-3-9.2
Boris Diaw-13.9-13.9-13.9-13.9
Brad Miller-3.2-8.300-1.2-2.3-4.2-8.3
Brendan Haywood-4.9-6.8-1.7-6.8-1.7-6.2
Brevin Knight-5-5-5-5
Brian Skinner-2.1-2.1-2.1-2.1
C.J. Watson-4.6-4.6-4.6-4.6
Carlos Boozer-0.4-1.72.3-1.7-1.62.3
Charlie Ward-5.8-5.8-5.8-5.8
Chauncey Billups32.53.72.73.72.5
Chris Andersen-4.3-4.3-4.3-4.3
Chris Bosh-2.6-3.8-1.6-1.8-1.6-3.8-3.2
Chris Paul-2.5-3.6-0.5-2.7-3.3-3.6-0.5
Chris Wilcox-9.4-9.4-9.4-9.4
Corey Maggette-8.6-8.6-8.6-8.6
Corliss Williamson-1.9-1.9-1.9-1.9
Danilo Gallinari-1.1-3.61.4-3.61.4
Danny Granger-2.3-5.4-0.1-1.5-5.4-0.1
Darvin Ham-3-3-3-3
David Lee-3.1-3.1-3.1-3.1
DerMarr Johnson-3.5-3.5-3.5-3.5
Deron Williams-1.5-4.51.51.5-4.5
Derrick Coleman4.34.34.34.3
Desmond Mason-2.2-2.8-1.7-2.8-1.7
Devin Harris-3.6-3.6-3.6-3.6
Dirk Nowitzki1-2.23.50.13.10.22.51.23.50.40.80.4-2.2
Doug Christie31.24.91.24.9
Dwight Howard-0.1-4.53.7-4.5-1.52.23.70.4-1
Dwyane Wade-4.5-9.6-0.9-0.9-3.6-9.6-4-4.5
Earl Boykins-2.2-2.2-2.2-2.2
Earl Watson0.40.40.40.4
Eddie Jones-3.4-4.8-2-4.8-2
Eddie Robinson-6.8-6.8-6.8-6.8
Elton Brand-2.2-4.8-0.3-3.8-0.3-1.1-2.2-4.8-0.9
Eric Gordon-5-5-5-5
Eric Snow-0.6-2.71.41.4-2.7
Etan Thomas-4.9-4.9-4.9-4.9
Gerald Wallace-3.9-6.6-0.3-6.2-2.4-0.3-6.6
Gilbert Arenas-3.9-3.9-3.9-3.9
Greg Ostertag2.92.92.92.9
Horace Grant-4-4-4-4
Ime Udoka-5.5-5.5-5.5-5.5
Jackie Butler-7.9-7.9-7.9-7.9
Jamal Crawford-5-5-5-5
Jason Collins-3.3-3.3-3.3-3.3
Jason Kidd0.3-2.53.32.43.3-0.2-1.5-2.50.1
Jason Richardson-4.9-6-3.9-3.9-6
Jason Smith-4.1-4.1-4.1-4.1
Jason Thompson-5.8-6-5.6-5.6-6
Jeff Foster-1.9-2.4-1.5-2.4-1.5
Jermaine O'Neal-1.2-41.7-1.21.7-4
Jerome James-1-1-1-1
Jim Jackson-1.9-1.9-1.9-1.9
Joe Johnson-3-4.7-1.2-4.7-1.2
Joe Smith-1-1-1-1
John Stockton-0.7-0.7-0.7-0.7
Josh Smith-2.7-7.21.2-7.21.2-2.9-1.8
Kevin Durant1.60.140.10.84
Kevin Garnett-0.4-7.85.30.1-0.6-0.2-1-5.2-7.83.95.32.2-1
Kevin Love-4.4-4.4-4.4-4.4
Kirk Hinrich-1.5-1.5-1.5-1.5
Kobe Bryant-0.1-3.74.5-2.7-1.7-3.71.34.51.6
Kurt Thomas-4.2-4.2-4.2-4.2
Kyle Lowry-0.6-0.9-0.2-0.9-0.2
LaMarcus Aldridge-0.4-2.92.6-2.92.60.4-0.5-1.5
Landry Fields0.90.90.90.9
LeBron James0.1-430.9-1.8-1.7-42.6-0.432.4
Luol Deng-0.3-4.54.3-1.1-1.61.5-4.5-2.92.54.3
Manu Ginobili1.71.71.71.71.7
Marc Gasol-3.1-3.1-3.1-3.1
Marcus Camby-5.9-9.6-0.9-0.9-9.6-7.2
Marko Jaric-6.3-6.3-6.3-6.3
Marvin Williams-5.8-5.8-5.8-5.8
Metta World Peace-2.9-6.41.1-6.41.1-3.5
Michael Jordan0.70.70.70.7
Michael Redd-6.4-7.7-5.1-5.1-7.7
Mike Conley-0.1-0.40.3-0.40.3
Mike Dunleavy-4.3-5.4-3.3-5.4-3.3
Mike James-5.1-5.6-4.6-4.6-5.6
Nate Robinson-7.4-7.4-7.4-7.4
Nene Hilario0.5-1.51.9-1.51.91.1
Nick Collison-6.6-6.6-6.6-6.6
Nick Van Exel-4-4-4-4
Othella Harrington-5.2-5.2-5.2-5.2
Pau Gasol-1.1-8.14.1-8.14.10.7
Paul Millsap-4.4-4.9-3.9-4.9-3.9
Paul Pierce-3-5.4-1.5-1.7-1.5-3.6-5.4
Quentin Richardson-3.3-3.3-3.3-3.3
Rafer Alston-0.3-3.52.9-3.52.9
Ramon Sessions-9.5-9.5-9.5-9.5
Rashad McCants-8.8-8.8-8.8-8.8
Rashard Lewis-2.8-8.63.7-3.53.7-8.6
Rasheed Wallace0.1-1.42.6-0.40.9-1.42.6-1.1
Ray Allen-1.8-62.6-51.1-62.6
Raymond Felton-3.1-3.1-3.1-3.1
Richard Hamilton3.63.63.63.6
Rodney Stuckey-6.6-7.7-5.5-5.5-7.7
Ronny Turiaf-3.7-3.7-3.7-3.7
Ruben Patterson-3.4-3.4-3.4-3.4
Rudy Gay-5.1-5.1-5.1-5.1
Ryan Bowen-4.4-4.4-4.4-4.4
Samuel Dalembert-4.7-4.7-4.7-4.7
Sebastian Telfair-5.3-5.3-5.3-5.3
Shane Battier-0.2-1.30.90.9-0.3-1.3
Shaquille O'Neal1.4-0.13.21.41-0.13.2
Shawn Marion-0.9-3.11.8-3.10.5-31.8
Speedy Claxton-3.8-5.4-2.1-2.1-5.4
Stephen Curry-4.2-4.4-4-4-4.4
Stephon Marbury-2.5-2.5-2.5-2.5
Steve Francis-2.3-4.7-1-4.7-1.2-1-2.4
Steve Nash-0.1-3.54.20.24.20.6-0.81.8-3.5-3
Stromile Swift-2.1-2.8-1.5-1.5-2.8
Thaddeus Young0.3-1.92.6-1.92.6
Theo Ratliff-6.6-9.7-4.1-4.1-6-9.7
Tim Duncan2.40.73.43.432.71.82.70.7223.2
Tracy McGrady2.213.413.4
Trevor Booker-7.7-7.7-7.7-7.7
Tyson Chandler0.2-2.52.9-2.52.9
Vince Carter-7.2-7.2-7.1-7.2-7.2-7.1
Vladimir Radmanovic0.60.60.60.6
Wilson Chandler-0.8-0.8-0.8-0.8
Yao Ming-1.2-4.31.9-4.31.9
Zach Randolph-6-6-6-6
Zaza Pachulia-5.1-5.1-5.1-5.1
Zydrunas Ilgauskas-7.6-7.6-7.6-7.6

One thought on “Supporting Casts are More Important Than Stars

  1. Great insight. One thing that occurs to me:

    We know that the star has intangible influence on his teammate, for good or for ill. The star contributes a lot to the resilience of his teammates. What this analysis of yours tells us is that even if the star has only a small fraction of the influence on his teammates play, that can easily overwhelm the impact he has on the court.

Leave a Reply

Your email address will not be published. Required fields are marked *

*