NBA Comeback Clutchness: Real or Just Noise? Sandy Huang and Toa Lohe

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1 1 NBA Comeback Clutchness: Real or Just Noise? Sandy Huang and Toa Lohe Introduction In his last NBA game, Kobe Bryant famously scored 60 points against the Utah Jazz to lead the Los Angeles Lakers to a victory. The game was entertaining not just because Kobe scored lots of points but because of how he scored those points. Let us set the scene. With about three minutes remaining in the 4 th quarter, the Lakers were down 10 points, and it seemed that Kobe would likely end his career with a loss despite having already scored 45 points. He, however, surprised us all by proceeding to score 15 straight points for the Lakers, a brilliant capstone performance to end a legendary 20-year career in the NBA. 1 At the end of the night, Kobe reminded everyone of why many of us watch sports in the first place: to feel the emotional suspense of seeing people struggle against and sometimes even overcome seemingly improbable odds. 2 This ability to overcome seemingly improbable odds is what we often nebulously call clutchness. Inspired by Kobe s last game, our final project quantified the clutchness of NBA players. In particular, we were interested in situations in which a player s team was either behind by 5 points (or less) or tied (but not ahead) in the last 5 minutes of the 4 th quarter (or overtime). Let us refer to this particular subset of clutchness as comeback clutchness. In contrast to comeback clutchness is escape clutchness when a player s team is either ahead by 5 points (or less) or tied (but not ahead) in the last 5 minutes of the 4 th quarter (or overtime). We made this particular distinction between comeback clutchness and escape clutchness because of both our assumption that there is a psychological difference between these two scenarios that significantly impacts how players perform and the fact the NBA does not provide data on situations where teams are only behind/ahead and not tied. Finally, one of the main aims of our project is to find out whether special comeback clutchness performances (e.g. Kobe s last game) can be repeated or if their manifestations are just noise (i.e. random). Background Previous work on NBA clutchness has been done by 82games 3 and Liberty Ballers 4 (a SB Nation blog for the Philadelphia 76ers). The first study done by 82games focused on the most clutch players in terms of field goals attempted, points scored, effective field goal percentage, foul drawing ability, and free throw shooting. The second study done by 82games focused on plusminus, win-loss record, rebounding, passing, and shot creation (based on unassisted field goals made per 48 minutes). The third study done by 82games focused on the difference between nonclutch and clutch moments, PER (Player Efficiency Rating), and opposing player PER. Lastly, the study done by Liberty Ballers focused on clutch shooting. None of these four studies, however, focused on comeback clutchness. 1 For the sake of Kobe s mythology, let s ignore the officiating shenanigans at the end (e.g. the Laker s Julius Randle setting hilariously illegal screens on the Jazz s Gordon Hayward). 2 Seth Partnow of VICE Sports more eloquently defined it as [t]hat anticipation, the moment just before the roller coaster tips over the crest of the big drop [...] the thrill that keeps us coming back

2 2 Methods By using Clutch Traditional Stats 5 and Clutch Advanced Stats 6 provided by the NBA, we formulated a comeback clutchness version of Justin Kubatko s Win Shares statistic (i.e. the estimated number of wins a player produces for his team). 7 Below are all the necessary conditions for a player s stats to be included in our analysis: 1) The statistic is accumulated in the last 5 minutes of the 4 th quarter (or overtime). 2) The player s team is either behind by 5 points (or less) or tied (but not ahead). 3) The player has played in at least a total of 50 minutes. In order to normalize for the total number of minutes played by each player, we also calculated comeback clutchness Win Shares Per To calculate Win Shares, Offensive Win Shares are added to Defensive Win Shares. Below are the details of calculating Offensive Win Shares and Defensive Win Shares: Player Points and Defensive Rating are already included in the player data provided by the NBA. 9 Additionally, Team Minutes 10 and Team Pace 11 are already included in the team data provided by the NBA. Below is a table detailing how to calculate the other statistics: Statistic Calculation Player Possessions Player Pace Minutes Played Usage Rate 13 Team Defensive Possessions Opponent s Total Points 14 Team Defensive Rating League Points Per Possession Total League Points Sum of Each Team s (Pace 48 Minutes Played) League Points Per Game Total League Points (Total Minutes Played 48) League Pace Sum of Each Team s (Pace 48 Minutes Played) (Total Minutes Played 48) 5 Comeback clutchness traditional player filter for analysis of season: 6 Comeback clutchness advanced player filter for analysis of season: Divide by the total number of minutes played and then multiplying by 48 9 See footnotes 5 and 6 10 Comeback clutchness traditional team filter for analysis of season: 11 Comeback clutchness advanced team filter for analysis of season: 12 See footnote 6 13 See footnote 6 14 Comeback clutchness opponent team filter for analysis of season: 15 See footnote 11 and Wikipedia:

3 3 In addition to this first analysis of comeback clutchness, we also conducted subsequent analysis on the value of comeback clutchness, the difference between comeback clutchness and escape clutchness, the difference between comeback clutchness and regular performance, and the repeatability of comeback clutchness. The value of comeback clutchness was measured as the differential between comeback clutchness Win Shares Per 48 and regular season Win Shares Per 48. The difference between comeback clutchness and escape clutchness was measured by using F-tests and t-tests, and the same method was used for the difference between comeback clutchness and regular performance. Finally, the repeatability of comeback clutchness was measured as the year-to-year correlation. We did these analyses for every season since the season and also looked at comeback clutchness plus-minus and PIE (Player Impact Estimate). 16 Results Comeback clutchness for the season: Top 10 Comeback Clutchness (WS/48) Bottom 10 Comeback Clutchness (WS/48) 1) Andre Drummond (1.10) 1) Isaiah Canaan (-0.92) 2) Stephen Curry (1.06) 2) Brandon Knight (-0.59) 3) Draymond Green (1.06) 3) Al-Farouq Aminu (-0.45) 4) Klay Thompson (0.90) 4) Mason Plumlee (-0.41) 5) Dirk Nowitzki (0.87) 5) Trevor Booker (-0.33) 6) LeBron James (0.85) 6) Damian Lillard (-0.29) 7) Deron Williams (0.79) 7) Rajan Rondo (-0.28) 8) Chandler Parsons (0.78) 8) PJ Tucker (-0.27) 9) Jeff Green (0.70) 9) Khris Middleton (-0.23) 10) Danilo Gallinari (0.69) 10) Robert Covington (-0.22) Value of comeback clutchness for the season: Top 10 Differential (WS/48) Bottom 10 Differential (WS/48) 1) Andre Drummond (0.97) 1) Isaiah Canaan (-0.95) 2) Draymond Green (0.87) 2) Brandon Knight (-0.64) 3) Klay Thompson (0.76) 3) Mason Plumlee (-0.55) 4) Stephen Curry (0.75) 4) Al-Farouq Aminu (-0.54) 5) Dirk Nowitzki (0.73) 5) Damian Lillard (-0.46) 6) Deron Williams (0.71) 6) Trevor Booker (-0.45) 7) Chandler Parsons (0.67) 7) Rajan Rondo (-0.36) 8) Jeff Green (0.64) 8) Russell Westbrook (-0.36) 9) LeBron James (0.61) 9) Khris Middleton (-0.33) 10) Jeremy Lin (0.60) 10) Serge Ibaka (-0.32) 16 PIE s explanation can be found here:

4 4 Comeback clutchness for the past 15 seasons: Top 5 Players by Comeback Clutchness Win Shares Per Andre Drummond Stephen Curry Draymond Green Klay Thompson Dirk Nowitzki Pau Gasol Joakim Noah Roy Hibbert Zach Randolph Jimmy Butler Greivis Vasquez Mike Conley James Harden Dirk Nowitzki Damian Lillard Chris Bosh Paul Pierce Jeff Green Ray Allen LeBron James Andrew Bynum Joe Johnson Udonis Haslem Roy Hibbert Zaza Pachulia Mo Williams Dirk Nowitzki Tyson Chandler Manu Ginobili Serge Ibaka LeBron James Kobe Bryant Dirk Nowitzki Marc Gasol Chauncey Billups Pau Gasol Dwight Howard Kobe Bryant Jason Terry Tony Parker LeBron James Stephen Jackson Chris Paul Amar'e Stoudemire Jeff Green Josh Howard Dirk Nowitzki Jason Terry Samuel Dalembert Jason Kapono Keith Bogans Chauncey Billups Chris Kaman Rasheed Wallace Earl Boykins Ben Gordon Chauncey Billups Tyson Chandler Kirk Hinrich Kenny Thomas Kobe Bryant Shaquille O'Neal Reggie Miller Metta World Peace Gary Payton Tony Battie Tony Delk Jason Terry Chauncey Billups Shareef Abdur-Rahim Raef LaFrentz Ervin Johnson Dirk Nowitzki Ryan Bowen Antonio Davis Bottom 5 Players by Comeback Clutchness Win Shares Per Isaiah Canaan Brandon Knight Al-Farouq Aminu Mason Plumlee Trevor Booker Tim Hardaway Jr. Jeremy Lin Rudy Gay Jordan Hill Wayne Ellington Trey Burke Gordon Hayward Ricky Rubio Ben McLemore Zaza Pachulia Greivis Vasquez Andrea Bargnani Arron Afflalo Jared Dudley Evan Turner Brandon Jennings Kris Humphries Tayshaun Prince Monta Ellis Brandon Knight Kirk Hinrich Stephen Curry Dorell Wright Luke Ridnour Monta Ellis George Hill Tyreke Evans Manu Ginobili Tayshaun Prince Mike Bibby Jason Richardson Peja Stojakovic Steve Nash Andrea Bargnani Rasheed Wallace Rashad McCants Tim Thomas Anthony Parker Carlos Delfino Chris Kaman Dahntay Jones Jarvis Hayes Luther Head Adam Morrison DeShawn Stevenson Luke Ridnour Donyell Marshall Steve Blake Jumaine Jones Rashard Lewis Tim Thomas Jarvis Hayes Keith Bogans Tony Parker Carlos Boozer Bobby Simmons Toni Kukoc Michael Finley Damon Jones Doug Christie Lamar Odom Corey Maggette Andre Miller Elton Brand Jason Richardson Bob Sura Bryon Russell Mark Jackson Larry Hughes Erick Dampier

5 5 Value of comeback clutchness for the past 15 seasons: Top 5 by Comeback Clutchness Win Shares Per 48 Differential Andre Drummond Draymond Green Klay Thompson Stephen Curry Dirk Nowitzki Joakim Noah Roy Hibbert Pau Gasol Zach Randolph Jimmy Butler Greivis Vasquez Mike Conley Taj Gibson Paul Pierce Klay Thompson Jeff Green Paul Pierce Chris Bosh Ray Allen Avery Bradley Andrew Bynum Joe Johnson Udonis Haslem Roy Hibbert Zaza Pachulia Mo Williams Dirk Nowitzki Tyson Chandler Manu Ginobili Jeff Green Kobe Bryant LeBron James Dirk Nowitzki Marc Gasol Jared Jeffries Jason Terry Pau Gasol Tony Parker Rashard Lewis Raja Bell LeBron James Stephen Jackson Jeff Green Baron Davis Nick Collison Josh Howard Dirk Nowitzki Jason Terry Samuel Dalembert Jason Kapono Keith Bogans Chris Kaman Earl Boykins Rasheed Wallace Carmelo Anthony Ben Gordon Tyson Chandler Chauncey Billups Kenny Thomas Kirk Hinrich Kobe Bryant Shaquille O'Neal Metta World Peace Al Harrington Alvin Williams Tony Battie Tony Delk Jason Terry Antoine Walker Glenn Robinson Raef LaFrentz Ervin Johnson Ryan Bowen Antonio Davis Dirk Nowitzki Bottom 5 by Comeback Clutchness Win Shares Per 48 Differential Isaiah Canaan Brandon Knight Mason Plumlee Al-Farouq Aminu Damian Lillard Rudy Gay Jeremy Lin Andre Drummond Chris Paul Jordan Hill Ricky Rubio Gordon Hayward Trey Burke Ramon Sessions Ben McLemore Greivis Vasquez Ryan Anderson Jared Dudley Blake Griffin John Wall Brandon Jennings Kris Humphries Tayshaun Prince Monta Ellis Greg Monroe Kirk Hinrich Stephen Curry Dorell Wright Luke Ridnour Monta Ellis George Hill Manu Ginobili Tyreke Evans Deron Williams Mike Bibby Jason Richardson Steve Nash Chris Paul Peja Stojakovic Nate Robinson Rashad McCants Anthony Parker Carlos Delfino Tim Thomas Chris Kaman Dahntay Jones Amar'e Stoudemire Luther Head Jarvis Hayes DeShawn Stevenson Luke Ridnour Donyell Marshall Steve Blake Rashard Lewis Jumaine Jones Tim Thomas Tony Parker Kobe Bryant Carlos Boozer Jarvis Hayes Bobby Simmons Toni Kukoc Michael Finley Damon Jones Jason Kidd Lamar Odom Corey Maggette Elton Brand Andre Miller Gilbert Arenas Bob Sura Bryon Russell Mark Jackson Andrei Kirilenko Mike Miller

6 6 Difference between comeback clutchness and escape clutchness (includes past 15 seasons): F-Test Two-Sample for Variances Escape Clutchness Comeback Clutchness Mean Variance Observations df F P(F<=f) one-tail F Critical one-tail t-test: Two-Sample Assuming Equal Variances Escape Clutchness Comeback Clutchness Mean Variance Observations Pooled Variance Hypothesized Mean Difference 0 df 3258 t Stat P(T<=t) one-tail E-13 t Critical one-tail P(T<=t) two-tail E-12 t Critical two-tail Since F < (F Critical one-tail), the variances of the two samples are equal, and, since (t Stat) >> (t Critical two-tail) and the p-value << 0, player performance in comeback clutchness situations is significantly different from that of escape clutchness situations. Difference between comeback clutchness and regular performance (includes past 15 seasons): F-Test Two-Sample for Variances Comeback Clutchness Regular Performance Mean Variance Observations df F P(F<=f) one-tail 0 F Critical one-tail t-test: Two-Sample Assuming Unequal Variances Comeback Clutchness Regular Performance Mean Variance Observations Hypothesized Mean Difference 0 df 1945 t Stat P(T<=t) one-tail E-86 t Critical one-tail P(T<=t) two-tail E-85 t Critical two-tail Since F >> (F Critical one-tail) and the p-value = 0, the variances of the two samples are unequal, and, since (t Stat) >> (t Critical two-tail) and the p-value 0, player performance in comeback clutchness situations is significantly different from that of regular performance situations.

7 7 Year-To-Year Correlation using comeback clutchness WS/48: R 2 = 0.02 (no correlation) Year-to-Year Correlation using comeback clutchness WS/48 differential: R 2 = 0.01 (no correlation)

8 8 Discussion Looking at our results, we seem to have produced some pretty intuitive results and also some very counterintuitive results. For instance, in the season, Andre Drummond had both the highest comeback clutchness Win Shares Per 48 (1.10) and the highest comeback clutchness Win Shares Per 48 differential (0.97). To be clear, this means Drummond s regular season Win Shares Per 48 was This is a very counterintuitive result given that opposing teams often hack Drummond near the end of games (i.e. foul him on purpose to send him to the free throw line where he shoots an abysmal 37.1%). It could be the case, however, that Drummond s comeback clutchness is so high because teams who are ahead may be less likely to employ the hacking strategy and thus Pistons coach Stan Van Gundy is not forced to take Drummond out of the game. It could also be the case that Drummond is often taken out of the game immediately after the first hacking foul and thus his comeback clutchness numbers are inflated. Other counterintuitive results include random appearances in the top five by some very marginal players 18 and bottom-five appearances by some marquee players in their prime like Damian Lillard ( season), Chris Paul ( season), Manu Ginobili ( season), and Kobe Bryant ( season). 19 In contrast to these counterintuitive results, we produced very intuitive ones like Stephen Curry, Draymond Green, and Klay Thompson being in the top five for both comeback clutchness Win Shares Per 48 and comeback clutchness Win Shares Per 48 differentials. Teams like the Dallas Mavericks who repeatedly won close games were also rewarded in our rankings (e.g. Dirk Nowitzki, Deron Williams, and Chandler Parsons) while an awful team like the Philadelphia 76ers was represented by their point guard Isaiah Canaan. Finally, the ever efficient LeBron James appears in both of our rankings. Conclusions Comeback clutchness is just noise (i.e. rarely repeatable) given its non-existent year-toyear correlation. It is, however, significantly different from both regular season performance and escape clutchness. The latter result confirms our assumption that there probably exists a psychological difference between playing behind and playing ahead that significantly impacts player performance, especially when it comes to clutch situations. Extensions of our project include performing the same kinds of analyses but with adjusted plus-minus and PIE. By using adjusted plus-minus, one could better account for differences in competition. By using PIE, our hypothesis is that more intuitive results can be gained (i.e. less random appearances in the top five by very marginal players), at least according to our preliminary analysis 20 of PIE. A downside, however, to using adjusted plus-minus and PIE is that neither statistic really tells you how many wins a player can produce for their team (although one could potentially argue that this is also true of Win Shares Per 48) = Specifically: Greivis Vasquez, Udonis Haslem, Zaza Pachulia, Jason Kapono, Keith Bogans, Earl Boykins, Kenny Thomas, Tony Battie, Tony Delk, Raef LaFrentz, Ervin Johnson, Ryan Bowen, Antonio Davis, Jared Jeffries, Nick Collison, and Alvin Williams 19 Along with Steve Nash ( season), Rashard Lewis ( season), Tony Parker ( season), Carlos Boozer ( season), Michael Finley ( season), Lamar Odom ( season), Elton Brand ( season), John Wall ( season), Brandon Jennings ( season), Deron Williams ( season), and Mike Miller ( season) 20 Looking at the top players for each of the last fifteen seasons

9 9 Appendix Top 5 Players by Comeback Clutchness Offensive Win Shares Per Stephen Curry Kevin Durant Andre Drummond Jeremy Lin Jamal Crawford Anthony Davis Dirk Nowitzki LaMarcus Aldridge James Harden Danny Green Mike Conley James Harden Damian Lillard Chris Bosh Iman Shumpert Dirk Nowitzki Ray Allen Jeff Green Jarrett Jack Jimmy Butler Andrew Bynum Kyrie Irving Kobe Bryant Nene Dwight Howard Dirk Nowitzki Mo Williams Eric Gordon Manu Ginobili Jason Richardson Kobe Bryant LeBron James Joe Johnson Steve Nash Dirk Nowitzki Zach Randolph Jason Terry Kobe Bryant Tony Parker Paul Pierce LeBron James Stephen Jackson Manu Ginobili Tim Duncan Vince Carter Mehmet Okur Zach Randolph Chauncey Billups Jason Kapono Dirk Nowitzki Jason Terry Earl Boykins Primoz Brezec Chauncey Billups Dwyane Wade Ray Allen Ben Gordon Earl Boykins Larry Hughes Chauncey Billups Kevin Garnett Kobe Bryant Yao Ming Metta World Peace Shareef Abdur-Rahim Shaquille O'Neal Derek Anderson Jason Terry Dirk Nowitzki Chris Webber Bonzi Wells Dirk Nowitzki Pat Garrity Ray Allen Antoine Walker Top 5 Players by Comeback Clutchness Defensive Win Shares Per Draymond Green Andre Drummond Jeff Green Reggie Jackson LeBron James Derrick Rose Joakim Noah Roy Hibbert Zach Randolph Luc Mbah a Moute Greivis Vasquez Joakim Noah Kirk Hinrich Taj Gibson Courtney Lee Chris Bosh Kevin Garnett Paul Pierce Rajon Rondo Avery Bradley Udonis Haslem Roy Hibbert Zaza Pachulia Jeff Teague Mario Chalmers Mo Williams Tyson Chandler Jason Kidd Tim Duncan Serge Ibaka Andrew Bogut Marc Gasol Jared Jeffries Lamar Odom Mike Conley Hedo Turkoglu Pau Gasol Dwight Howard Rashard Lewis Lamar Odom Jeff Green Shaquille O'Neal Chris Paul Nick Collison Daniel Gibson Josh Howard Dirk Nowitzki Jason Terry Monta Ellis Andre Miller Keith Bogans Chris Kaman Elton Brand Marcus Camby Chauncey Billups Tyson Chandler Kirk Hinrich Ben Gordon Stephen Jackson Ben Wallace Shaquille O'Neal Kobe Bryant Al Harrington Reggie Miller Jermaine O'Neal Tony Battie Tony Delk Antoine Walker Darius Miles Christian Laettner Ryan Bowen Raef LaFrentz James Posey Ervin Johnson Vin Baker

10 10 Bottom 5 Players by Comeback Clutchness Offensive Win Shares Per Robert Covington Derrick Rose Khris Middleton Isaiah Canaan Brandon Knight Derrick Rose Bradley Beal Rudy Gay Michael Carter-Williams Steven Adams Brandon Jennings Dion Waiters Ramon Sessions Ben McLemore Gerald Green John Wall Carlos Delfino Jared Dudley Luis Scola Byron Mullens Brandon Jennings O.J. Mayo Jameer Nelson Nicolas Batum Jason Kidd Luke Ridnour Vince Carter Tony Parker Brandon Jennings DeMarcus Cousins Rodney Stuckey Corey Brewer Eric Gordon Jamal Crawford Aaron Brooks Metta World Peace Rasheed Wallace Baron Davis LaMarcus Aldridge Jason Richardson Kirk Hinrich Gerald Wallace Antonio McDyess Chris Kaman Dwyane Wade Luther Head Randy Foye Jason Kidd Hedo Turkoglu Jameer Nelson Jumaine Jones Anthony Johnson Mark Blount Raef LaFrentz Deron Williams Keith Bogans Kobe Bryant David Wesley Tony Delk Speedy Claxton Allen Iverson Toni Kukoc Michael Finley Eric Williams Jamal Crawford Darius Miles Larry Hughes Scottie Pippen Troy Hudson Kenyon Martin LaPhonso Ellis Bryon Russell Derrick Coleman Baron Davis Terry Porter Bottom 5 Players by Comeback Clutchness Defensive Win Shares Per Isaiah Canaan Mason Plumlee CJ McCollum Damian Lillard Brandon Knight Jeremy Lin Tim Hardaway Jr. Jordan Hill James Harden Marcin Gortat Trey Burke Gordon Hayward Corey Brewer Ricky Rubio Zaza Pachulia Ben Gordon Ryan Anderson Chris Paul Jamal Crawford Anthony Davis Kris Humphries Monta Ellis Greg Monroe Brandon Jennings Brandon Knight Kirk Hinrich Stephen Curry Dorell Wright Monta Ellis DeMar DeRozan Tyreke Evans Mike Bibby George Hill Jason Richardson Beno Udrih Jason Richardson Steve Nash Chris Paul Peja Stojakovic Rasual Butler Rashad McCants Anthony Parker Carlos Delfino Ryan Gomes Al Jefferson Amar'e Stoudemire LaMarcus Aldridge Dahntay Jones DeShawn Stevenson Jarvis Hayes Donyell Marshall Rashard Lewis P.J. Brown Luke Ridnour Steve Blake Tim Thomas Carlos Boozer Manu Ginobili Josh Childress Jarvis Hayes Bobby Simmons Ray Allen Damon Jones Brad Miller Steve Nash Lamar Odom Corey Maggette Charlie Ward Andre Miller Elton Brand Bonzi Wells Bob Sura Bryon Russell Erick Dampier Ron Mercer