The Wins Produced Calculation

 

The following is a step-by-step guide to the Wins Produced calculation.

As noted below, these steps are detailed both in The Wages of Wins and in Berri (2008).

The steps in the book, though, left out the math.  So hopefully the following example (with the math) will be helpful.

 

The example provided here focuses on Bob Lanier and the 1977-78 Detroit Pistons.

 

Preliminary Step A:             

Link wins to offensive and defensive efficiency. 

This simple model was noted by both Dean Oliver (2004) and John Hollinger (2002).  In Berri (2008) this model is developed mathematically. For here, though, we are going to simply take the link between wins and the efficiency measures as given. [One can read Berri (2008) for the math].

                   

Here is the specific model linking winning percentage to offensive and defensive efficiency.

The model was estimated with data from 1977-78 to 1990-91.

Data taken from Basketball-Reference.com

 

Dependent Variable is Winning Percentage

Independent Variable

Coefficient

t-statistic

Offensive Efficiency

3.442

62.6

Defensive Efficiency

-3.447

-60.2

Constant term

0.535

10.4

Adjusted R2 = 0.93

 

Where

Offensive Efficiency = Points Scored divided by Possessions Employed (PE)

Defensive Efficiency = Points Surrendered divided by Possessions Acquired (PA)

 

Where

PE = FGA + 0.47*FTA + TO – REBO

PA = DFGM + 0.47*DFTM + REBD + DTO + REBTM

 

Where

FGA = Field Goal Attempts

FTA = Free Throw Attempts

TO = Turnovers 

REBO = Offensive Rebounds

DFGM = Opponent’s Field Goals Made

DFTM = Opponent’s Free Throws Made

REBD = Defensive Rebounds

DTO = Opponent’s Turnovers

REBTM = Team Rebounds

 

The formulation for PE and PA is explained in Berri (2008).

The value for FTA and DFTM is explained in Berri (2008)

REBTM refers to Team Rebounds that change possession.  This calculation is detailed in the book and Berri (2008)

 

Preliminary Step B:              

Determine the value, in terms of wins, of points and possessions. 

This is done by differentiating the above wins model with respect to Points, Points Surrendered, PE, and PA.

 

Table One

The Value of Points and Possessions

Variable

Label

Marginal Value

Points Scored

PTS

0.032

Possessions Employed

PE

-0.032

Points Surrendered

DPTS

-0.032

Possessions Acquired

PA

0.033

 

 

Preliminary Step C:              

With the value of PTS, DPTS, PE, and PA determined, we can now ascertain the value of all the individual elements of offensive and defensive efficiency (i.e. PTS, FGA, ORB, etc…).  These values are detailed in The Wages of Wins.  The model estimated for the paperback, though, employed data from 1991-92 through the 2006-07 season.  One should note that across the earlier time period the values for the individual statistics are basically the same.

 

One should also note the values for blocked shots and assists are not taken from the efficiency model.  Further regressions are used to get at these two factors. For details one is referred to Berri (2008) and The Wages of Wins. 

 

The value of personal fouls, again as detailed in The Wages of Wins and Berri (2008), is calculated from the value of the opponent’s free throws made.  Specifically, we first determine the percentage of personal fouls a player committed on a team.  We then multiply this percentage by the number of free throws the opponent of a team made.  For example, Bob Lanier committed 9.3% of Detroit’s personal fouls in 1977-78.  Detroit’s opponents made 1,662 free throws, so Lanier is charged with 155.3 FTM(opp.).

 

Table Two

Value of Player and Team Statistics

Player Variables

Marginal Value

Three Point Field Goals Made (3FGM)

0.064

Two Point Field Goals Made (2FGM)

0.032

Free Throws Made (FTM)

0.017

Missed Field Goals (FGMS)

-0.032

Missed Free Throws (FTMS)

-0.015

Offensive Rebounds (REBO)

0.032

Defensive Rebounds (REBD)

0.033

Turnovers (TO)

-0.032

Steals (STL)

0.033

Opponent's Free Throws Made [FTM(opp.)]

-0.017

Blocked Shots (BLK)

0.019

Assists (AST)

0.022

Team Variables

Marginal Value

Opponent's Three Point Field Goals Made [3FGM(opp.)]

-0.064

Opponent's Two Point Field Goals Made [2FGM(opp.)]

-0.032

Opponent's Turnovers [TO(opp.)]

0.033

Team Turnovers (TOTM)

-0.032

Team Rebounds (REBTM)

0.033

 

 

CALCULATING WINS PRODUCED

 

Step One:         

Calculate the value of a player’s production (PROD). 

 

The three point shot did not exist in 1977-78 so this value can be ignored. But the other statistics were tabulated.

 

PROD =     2FGM*0.032 + FTM*0.017 + FGMS*-0.032 + FTMS*-0.015 + REBO*0.032 + REBD*0.033 + TO*-0.032 + STL*0.033 + FTM(opp.)*-0.017 + BLK*0.019 + AST*0.022

 

For Bob Lanier in 1977-78 the calculation would be as follows:

 

Lanier PROD =  622*0.032 + 298*0.017 + 537*-0.032 + 88*-0.015 + 197*0.032 + 518*0.033 + 225*-0.032 + 82*0.033 + 155.3*-0.017 + 93*0.019 + 216*0.022 = 28.57

 

Step Two:

Adjust for teammate’s production of blocked shots and assists and calculate P48

                  

Blocked shots and assists do not impact wins directly.  Neither of these stats are a part of offensive or defensive efficiency.  But each stat, as detailed in The Wages of Wins, do have an impact on factors that are part of offensive and defensive efficiency.  In calculating PROD the player was credited with the value of his block shots and assists. Now we have to account for the impact of teammates blocked shots and assists on the player’s productivity.

 

To do this we calculate MATE48.  For each team we take the accumulation of blocked shots and assists and multiply each stat by the corresponding value found in Table Two.  We then determine the value a team creates from its blocked shots and assists per 48 minutes played (by dividing the value of blocked shots and assists by total minutes played and multiplying this by 48).

 

For example, the Pistons in 1977-78 blocked 330 shots and accumulated 1840 assists.  Given the value of blocked shots (0.019) and assists (0.022), and 19,855 minutes played, we do the following calculation:

                  

Per 48 minute value of blocked shots and assists = [(330*0.019+ 1840*0.022) / 19,855] * 48 = 0.1145.

 

The average NBA team in 1977-78 had a per 48 minute value of blocked shots and assists of 0.1305.  MATE48 is simply the difference between the team value and the league average.

         

MATE48 =          Per 48 minute value of a team’s blocked shots and assists – Average per 48 minutes value of blocked shot and assist

 

Pistons MATE48 = 0.1145 – 0.1305 = - 0.016

         

MATE48 is incorporated into each player’s value by subtracting MATE48 from each player’s PROD per 48 minutes.  The outcome of this calculation is called P48.

 

Lanier P48 = [(PROD / Minutes Played)*48] – MATE48 = [(28.57 / 2,311)*48] – (-0.016) = 0.609

 

Table Three

Value of MATE48 in 1977-78

Team

MATE48

Atlanta

-0.009

Boston

-0.010

Buffalo

-0.009

Chicago

-0.001

Cleveland

-0.016

Denver

0.007

Detroit

-0.016

Golden State

0.002

Houston

-0.010

Indiana

-0.002

Kansas City

-0.006

Los Angeles

0.009

Milwaukee

0.015

New Jersey

0.000

New Orleans

0.006

New York

0.015

Philadelphia

0.015

Phoenix

0.013

Portland

0.000

San Antonio

0.017

Seattle

-0.013

Washington

-0.007

 

 

The average value, in absolute terms, of MATE48 is 0.009.  The average value of PROD48 in the league is 0.304. MATE48 has very little impact on our assessment of individual players. The correlation coefficient between PROD48 and P48 in 1977-78 was 0.9986.  

 

Step Three:

Incorporate team defense and calculate adjusted P48. 

 

From Table Two we see that there are five factors tracked for the team that are not tracked for individual players.  These include 3FGM(opp.), 2FGM(opp.), TO(opp.), TOTM, and REBTM.  Each of these statistics are tracked for the team, but not assigned to individual players.

 

These are team defensive factors, and these are allocated across the players according to the minutes the player plays.  In other words, we treat defense as a team activity, not an individual action. 

 

This approach allows us to differentiate players who play on good and bad defensive teams. But the data limitations prevent us from differentiating between players who are relatively better or worse on an individual team.  It may be possible to utilize plus-minus data to overcome this limitation, but until that happens, we utilize DEFTM48 in our evaluation of individual players. 

 

The calculation of DEFTM48 begins with the Team Defense Adjustment.

 

Team Defense Adjustment =  [(2FGM(opp.)*-0.032 + TO(opp.)*0.033 + TOTM*-0.032 + REBTM*0.033)/Minutes Played]*48

 

Pistons Team Defensive Adjustment = [(3688*-0.032 + 853*0.033 + 18*-0.032 + 437.7*0.033)/19,855]*48 = -0.1839   

 

To calculate DEFTM48 we compare each team’s defensive adjustment to the league average.

 

DEFTM48 = League Average Team Defensive Adjustment - Team Defensive Adjustment

 

Pistons DEFTM48 = -0.1734 - -0.1839 = 0.010

 

DEFTM48 is incorporated into each player’s value by subtracting DEFTM48 from each player’s P48.  The outcome of this calculation is called Adj. P48.

 

Lanier Adj. P48 = 0.609 - (0.010) = 0.599

 

 Table Four

Value of DEFTM48 in 1977-78

Team

DEFTM48

Atlanta

-0.030

Boston

0.006

Buffalo

0.005

Chicago

0.014

Cleveland

-0.008

Denver

0.014

Detroit

0.010

Golden State

-0.001

Houston

0.011

Indiana

0.004

Kansas City

-0.002

Los Angeles

0.011

Milwaukee

-0.001

New Jersey

-0.022

New Orleans

0.017

New York

0.004

Philadelphia

-0.001

Phoenix

-0.014

Portland

-0.018

San Antonio

0.013

Seattle

-0.025

Washington

0.010

 

The average value, in absolute terms, of DEFTM48 is 0.011, so again this is a very small adjustment. And as we saw with MATE48, DEFTM48 has very little impact on our assessment of individual players. The correlation coefficient between P48 and Adj. P48 in 1977-78 was 0.9977.

 

Step Four:

Adjusting for position played.

 

The average value for Adj. P48 is 0.304.  But this value is not the same across all positions.  As noted in The Wages of Wins, centers and power forwards get rebounds and tend not to commit turnovers.  Guards are the opposite.  The nature of basketball is that teams need guards, small forward, and big men.  Given nature of the game, players have to be compared to their position averages.  These are reported in Table Five.

 

Table Five

Value of Adj. P48 Across Positions

Position

Average Adj. P48

Centers and Power Forwards

0.420

Small Forwards

0.286

Guards

0.196

 

 

Previously averages were calculated for all five positions.  Centers and power forwards tend to have the same averages across time.  Furthermore, it is sometimes not clear who is the power forward or the center.  Hence, it doesn’t appear that much is lost if we simply treat centers and power forwards as the same position.  A similar argument can be offered for shooting guards and point guards.  Basically, what we see is that big men are different from guards and that needs to be noted in the evaluation of players.  Trying to differentiate positions further seems unnecessary.

 

One last note…as detailed below, the average productivity of a big man in 1977-78 is higher than what we see today.  And the productivity of guards was lower in the 1970s.  It was once believed that you needed a dominant big man to compete in the NBA.  Certainly these results suggest that was true three decades ago.

 

To incorporate the position averages we need to identify the position each player plays.  For most players this is easy.  For a few, though, it can be more challenging. 

 

For the 1977-78 season I am began with position data that was provided by Dean Oliver. 

 

Table Six

Position Data for the Detroit Pistons in 1977-78

Pistons 77-78

Minutes

Played

Position

Number

Position

Code

Height

Weight

Bob Lanier

2,311

5.0

C

6-11

256

Leon Douglas

1,993

4.5

FC

6-10

230

John Shumate

2,170

4.5

FC

6-9

235

Ben Poquette

626

4.5

FC

6-9

235

Howard Porter

107

4.5

FC

6-8

220

Marvin Barnes

269

4.5

FC

6-8

210

Willie Norwood

260

3.5

F

6-7

220

Al Eberhard

576

3.5

F

6-6

225

Jim Bostic

48

3.0

SF

6-7

225

Gus Gerard

805

2.5

GF

6-8

200

Ralph Simpson

739

2.5

GF

6-5

200

M.L. Carr

2,556

1.5

G

6-6

205

Chris Ford

2,582

1.5

G

6-5

190

Al Skinner

1,274

1.5

G

6-4

195

Jim Price

839

1.5

G

6-3

195

Wayman Britt

16

1.5

G

6-2

185

Kevin Porter

127

1.5

G

6-0

175

Eric Money

2,557

1.5

G

6-0

170

 

It is important to note that positions in basketball are not like baseball or football.  In baseball and football we can tell position by where a player appears on the field.  In basketball, though, position designations are more arbitrary.  Consequently, two analysts looking at the same team may designate positions differently. 

 

Here is the process I followed for the 1977-78 season.

1.  Minutes are equal at each position

2. In general, players are allocated across the center and forwards position according to Oliver’s designation and then by height and weight.

3. At the guard positions again we look at position designation, height, and weight.  But I also consider number of assists per minute.  The players who get more assists are generally considered point guards (although given that we are not differentiating between guards with respect to the league averages, the distinction between shooting and point guards is not important).

 

Given this process, here is my allocation for the Pistons in 1977-78.

 

Table Seven

Allocating Player across Positions

Centers

Minutes at Position

Bob Lanier

2,311

Leon Douglas

1,660

 

3,971

Power Forwards

 

John Shumate

2,170

Ben Poquette

626

Leon Douglas

333

Marvin Barnes

269

Willie Norwood

260

Al Eberhard

206

Howard Porter

107

 

3,971

Small Forwards

 

M.L. Carr

2,556

Gus Gerard

805

Al Eberhard

370

Ralph Simpson

192

Jim Bostic

48

 

3,971

Shooting Guards

 

Chris Ford

1,311

Al Skinner

1,274

Jim Price

839

Ralph Simpson

547

 

3,971

Point Guards

 

Eric Money

2,557

Chris Ford

1,271

Kevin Porter

127

Wayman Britt

16

 

3,971

           

With positions ascertained, we can now calculate a player’s performance relative to the position average.  For Lanier the calculation would be as follows:

 

Lanier Relative Adj. P48 = Adj. P48 – League Average Adj. P48 = 0.599 – 0.420 = 0.179

 

So per 48 minutes, Lanier produced 0.179 more wins than an average center. Given that he played 2,311 minutes, we can now see that Lanier produced 8.6 wins more than the average center.

 

Before moving on, what about a player like Ralph Simpson?  Simpson is listed at small forward and shooting guard.  To assess his productivity, we need to compare Simpson to an average small forward and an average shooting guard.   This is done as follows:

 

Simpson’s Relative Adj. P48 at small forward = 0.084 – 0.286 = -0.202

Simpson’s Relative Adj. P48 at shooting guard = 0.084 – 0.196 = -0.112

We then weight these two calculations according to the time Simpson spent at each position.  After this calculation we see that Simpson, per 48 minutes, produced 0.135 less than an average player at the position he played (so his Relative Adj. P48 was -0.135).

 

Step Five: 

Calculating WP48 and Wins Produced

 

If we stop after Step Four we will have a player’s production relative to the position average. What we want is a player’s Wins Produce per 48 minutes (WP48) and his Wins Produced.

 

As noted in The Wages of Wins, to move from relative wins to absolute wins you need to note the average number of wins produced by a player per 48 minutes.  This is quite easy to calculate.

 

The average team will win 0.500 games.  Since a team employs five players per 48 minutes, the average player must produce per 48 minutes 0.100 wins.  Because teams do play overtime games once in awhile, the actual average production of wins per 48 minutes is 0.099 (and one should note, all this is true regardless of how you calculate Wins Produced).

 

Given what we know about an average player, WP48 is calculated as follows:

 

WP48 = Relative Adj. P48 + 0.099

 

For Lanier the calculation is as follows:

 

Lanier WP48 = 0.179 + 0.099 = 0.278

 

Lanier played 2,311 minutes.  If he produced 0.278 wins per 48 minutes he must have produced 13.4 wins for the season.

 

Lanier Wins Produced = WP48 / 48 * Minutes Played = 0.278/48 * 2,311 = 13.4 

 

Or you can think of it this way.  An average player would have produced 4.8 wins in Lanier’s minutes.  We saw in Step Four that Lanier produced 8.6 wins more than the average center.  Therefore Lanier’s Wins Produced must be 13.4.

 

Table Eight reports the calculation for each player the Pistons employed in 1977-78.  Again, an average team would win 41 games, and an average position would produce 8.2 victories.  Looking over the roster, it appears the Pistons were only above average at center.  Their weakest position was power forward.  Although John Shumate was above average at the (4) spot, the remaining power forwards employed were well below average.

 

Table Eight

Calculating Wins Produced for the Pistons in 1977-78

Pistons

Minutes at Position

Adj. P48

Position Average

Relative Adj. P48

WP48

Wins Produced

Centers

 

 

 

 

 

 

Bob Lanier

2,311

0.599

0.420

0.179

0.278

13.4

Leon Douglas

1,660

0.353

0.420

-0.067

0.032

1.1

Position Totals

3,971

 

 

 

 

14.5

Power Forwards

 

 

 

 

 

 

John Shumate

2,170

0.454

0.420

0.034

0.133

6.0

Ben Poquette

626

0.225

0.420

-0.195

-0.095

-1.2

Leon Douglas

333

0.353

0.420

-0.067

0.032

0.2

Marvin Barnes

269

0.337

0.420

-0.083

0.016

0.1

Willie Norwood

260

0.205

0.420

-0.215

-0.116

-0.6

Al Eberhard

206

0.213

0.420

-0.207

-0.108

-0.5

Howard Porter

107

0.038

0.420

-0.382

-0.283

-0.6

Position Totals

3,971

 

 

 

 

3.4

Small Forwards

 

 

 

 

 

 

M.L. Carr

2,556

0.321

0.286

0.035

0.134

7.2

Gus Gerard

805

0.193

0.286

-0.092

0.007

0.1

Al Eberhard

370

0.213

0.286

-0.072

0.027

0.2

Ralph Simpson

192

0.084

0.286

-0.202

-0.103

-0.4

Jim Bostic

48

0.468

0.286

0.182

0.281

0.3

Position Totals

3,971

 

 

 

 

7.4

Shooting Guards

 

 

 

 

 

 

Chris Ford

1,311

0.246

0.196

0.050

0.149

4.1

Al Skinner

1,274

0.136

0.196

-0.060

0.039

1.0

Jim Price

839

0.161

0.196

-0.034

0.065

1.1

Ralph Simpson

547

0.084

0.196

-0.112

-0.013

-0.1

Position Totals

3,971

 

 

 

 

6.1

Point Guards

 

 

 

 

 

 

Eric Money

2,557

0.138

0.196

-0.058

0.041

2.2

Chris Ford

1,271

0.246

0.196

0.050

0.149

3.9

Kevin Porter

127

0.305

0.196

0.109

0.208

0.6

Wayman Britt

16

0.113

0.196

-0.083

0.016

0.0

Position Totals

3,971

 

 

 

 

6.7

Team Totals

19,855

 

 

 

 

38.0

 

 

Although Lanier was clearly the most productive player on this team, Chris Ford, M.L. Carr, and Shumate were above average.  In fact, Lanier, Ford, Carr, and Shumate produced 34.6 of this team’s 38.0 Wins Produced.

 

Table Nine

Ranking the Pistons of 1977-78 in terms of Wins Produced

Pistons

Position

Played

Minutes

Played

ADJ P48

WP48

Wins

Produced

Bob Lanier

5.00

2,311

0.599

0.278

13.4

Chris Ford

1.51

2,582

0.246

0.149

8.0

M.L. Carr

3.00

2,556

0.321

0.134

7.2

John Shumate

4.00

2,170

0.454

0.133

6.0

Eric Money

1.00

2,557

0.138

0.041

2.2

Leon Douglas

4.83

1,993

0.353

0.032

1.3

Jim Price

2.00

839

0.161

0.065

1.1

Al Skinner

2.00

1,274

0.136

0.039

1.0

Kevin Porter

1.00

127

0.305

0.208

0.6

Jim Bostic

3.00

48

0.468

0.281

0.3

Gus Gerard

3.00

805

0.193

0.007

0.1

Marvin Barnes

4.00

269

0.337

0.016

0.1

Wayman Britt

1.00

16

0.113

0.016

0.0

Al Eberhard

3.36

576

0.213

-0.021

-0.3

Ralph Simpson

2.26

739

0.084

-0.036

-0.6

Willie Norwood

4.00

260

0.205

-0.116

-0.6

Howard Porter

4.00

107

0.038

-0.283

-0.6

Ben Poquette

4.00

626

0.225

-0.095

-1.2

Totals

 

19,855

 

 

38.0

 

 

As noted, the summation of Wins Produced for this team was 38.0.  And the Pistons actually did win 38 games in 1977-78.   Table Ten reports for each team the summation of Wins Produced and actual wins.  As one can see, the average difference – in absolute terms – is 2.3 wins.  Again, Wins Produced is based on a model connecting wins to offensive and defensive efficiency.  So the small difference between actual wins and the Summation of Wins Produced simply reflects the fact that the efficiency metrics do indeed explain team wins in the NBA. 

 

Table Ten

Reviewing the Accuracy of Wins Produced in 1977-78

Team

Actual

Wins

Summation of

Wins Produced

Difference in

Absolute Terms

Atlanta

41

40.9

0.1

Boston

32

36.1

4.1

Buffalo

27

31.3

4.3

Chicago

40

38.7

1.3

Cleveland

43

42.6

0.4

Denver

48

43.4

4.6

Detroit

38

38.0

0.0

Golden State

43

42.0

1.0

Houston

28

30.4

2.4

Indiana

31

34.6

3.6

Kansas City

31

36.3

5.3

Lakers

45

48.2

3.2

Milwaukee

44

40.0

4.0

New Jersey

24

26.2

2.2

New Orleans

39

36.2

2.8

New York

43

40.1

2.9

Philadelphia

55

54.8

0.2

Phoenix

49

51.0

2.0

Portland

58

57.2

0.8

San Antonio

52

49.9

2.1

Seattle

47

45.3

1.7

Washington

44

45.3

1.3

 

 

Average Difference

2.3

 

Here are the top 50 players in Wins Produced in 1977-78.  Notice that big men dominate the rankings.  Again, it was widely believed that you needed a dominant big man to compete in the NBA back in the 1970s.  The Wins Produced calculations are consistent with that belief.

 

Table Eleven

The Top 50 Players in 1977-78

Rank

Wins Produced

Top 50 Player

Team

Position

Played

Games

Played

Minutes

Played

Adj. P48

WP48

Wins

Produced

1

Kareem Abdul-Jabbar

LA Lakers

5.00

62

2,265

0.758

0.438

20.6

2

Artis Gilmore

Chicago

5.00

82

3,067

0.605

0.284

18.1

3

Bill Walton

Portland

5.00

58

1,929

0.771

0.451

18.1

4

Dave Cowens

Boston

5.00

77

3,215

0.576

0.255

17.1

5

Wes Unseld

Washington

5.00

80

2,644

0.626

0.305

16.8

6

Marques Johnson

Milwaukee

3.58

80

2,765

0.547

0.283

16.3

7

George Gervin

San Antonio

2.00

82

2,857

0.367

0.270

16.1

8

Marvin Webster

Seattle

5.00

82

2,910

0.580

0.259

15.7

9

David Thompson

Denver

2.00

80

3,025

0.340

0.243

15.3

10

Adrian Dantley

Indiana-LA Lakers

3.00

79

2,933

0.428

0.241

14.7

11

Bob McAdoo

New York

5.00

79

3,182

0.526

0.205

13.6

12

Bob Lanier

Detroit

5.00

63

2,311

0.599

0.278

13.4

13

Swen Nater

Buffalo

5.00

78

2,778

0.552

0.231

13.4

14

John Lucas

Houston

1.00

82

2,933

0.311

0.215

13.1

15

Bobby Jones

Denver

4.00

75

2,440

0.565

0.244

12.4

16

Foots Walker

Cleveland

1.00

81

2,496

0.335

0.238

12.4

17

Julius Erving

Philadelphia

2.88

74

2,429

0.411

0.235

11.9

18

Moses Malone

Houston

5.00

59

2,107

0.589

0.269

11.8

19

Don Buse

Phoenix

2.00

82

2,547

0.312

0.216

11.4

20

Rich Kelley

New Orleans

5.00

82

2,119

0.577

0.257

11.3

21

Dan Issel

Denver

5.00

82

2,851

0.507

0.187

11.1

22

Charles Dudley

Golden State

1.00

78

1,660

0.412

0.316

10.9

23

Clifford Ray

Golden State

4.88

79

2,268

0.550

0.229

10.8

24

Dan Roundfield

Indiana

4.15

79

2,423

0.534

0.213

10.7

25

Walter Davis

Phoenix

2.99

81

2,590

0.376

0.191

10.3

26

John Drew

Atlanta

3.00

70

2,203

0.405

0.218

10.0

27

Paul Westphal

Phoenix

1.00

80

2,481

0.289

0.192

9.9

28

Kevin Porter

Detroit-New Jersey

1.00

82

2,813

0.266

0.169

9.9

29

Billy Paultz

San Antonio

5.00

80

2,479

0.504

0.184

9.5

30

Norm Van Lier

Chicago

1.86

78

2,524

0.276

0.179

9.4

31

Elmore Smith

Cleveland

5.00

81

1,996

0.545

0.224

9.3

32

Bob Gross

Portland

3.00

72

2,163

0.392

0.206

9.3

33

Truck Robinson

New Orleans

3.73

82

3,638

0.405

0.120

9.1

34

Sam Lacey

Kansas City

5.00

77

2,131

0.523

0.202

9.0

35

Elvin Hayes

Washington

4.00

81

3,246

0.451

0.130

8.8

36

Butch Beard

New York

1.00

79

1,979

0.306

0.210

8.6

37

Randy Smith

Buffalo

2.00

82

3,314

0.220

0.123

8.5

38

Kermit Washington

Boston-LA Lakers

4.28

57

1,617

0.567

0.246

8.3

39

Sonny Parker

Golden State

2.97

82

2,069

0.376

0.192

8.3

40

Ricky Sobers

Indiana

1.00

79

3,019

0.225

0.129

8.1

41

Chris Ford

Detroit

1.51

82

2,582

0.246

0.149

8.0

42

Gus Williams

Seattle

1.00

79

2,572

0.246

0.149

8.0

43

Darryl Dawkins

Philadelphia

5.00

70

1,722

0.543

0.222

8.0

44

Cedric Maxwell

Boston

3.20

72

1,213

0.526

0.313

7.9

45

Steve Hawes

Atlanta

4.21

75

2,325

0.484

0.163

7.9

46

Mike Gale

San Antonio

1.53

70

2,091

0.277

0.181

7.9

47

Bernard King

New Jersey

3.04

79

3,092

0.313

0.122

7.9

48

Quinn Buckner

Milwaukee

1.00

82

2,072

0.274

0.177

7.7

49

Fred Brown

Seattle

2.00

72

1,965

0.273

0.176

7.2

50

Dave Twardzik

Portland

1.00

75

1,820

0.285

0.189

7.2

 

 

 

 

CALCULATING WINS PRODUCED FOR 2006-07

 

The basic wins model was estimated with data from the 1991-92 through the 2006-07 season.

Here are the values for the player and team statistics (notice how similar these values are to what we saw in Table Two)

 

Table Twelve

Value of Player and Team Statistics

1991-92 to 2006-07

Player Variables

 

Marginal Value

Three Point Field Goals Made (3FGM)

 

0.06493

Two Point Field Goals Made (2FGM)

 

0.03207

Free Throws Made (FTM)

 

0.01770

Missed Field Goals (FGMS)

 

-0.03364

Missed Free Throws (FTMS)

 

-0.01516

Offensive Rebounds (REBO)

 

0.03364

Defensive Rebounds (REBD)

 

0.03344

Turnovers (TO)

 

-0.03364

Steals (STL)

 

0.03344

Opponent's Free Throws Made [FTM(opp.)]

 

-0.01759

Blocked Shots (BLK)

 

0.01755

Assists (AST)

 

0.02228

Team Variables

 

Marginal Value

Opponent's Three Point Field Goals Made [3FGM(opp.)]

 

-0.06454

Opponent's Two Point Field Goals Made [2FGM(opp.)]

 

-0.03188

Opponent's Turnovers [TO(opp.)]

 

0.03344

Team Turnovers (TOTM)

 

-0.03364

Team Rebounds (REBTM)

 

0.03344

 

 

 

Given the values in Table Twelve, here are the steps in calculating Wins Produced

 

 

Step 1:      Calculate PROD

 

PROD =    3FGM*0.065 + 2FGM*0.032 + FTM*0.018 + FGMS*-0.034 + FTMS*-0.015 + REBO*0.034 + REBD*0.033 + TO*-0.034 + STL*0.034 + FTM(opp.)*-0.018 + BLK*0.018 + AST*0.022

 

Step 2:      Adjust for MATE48 and calculate P48

 

PROD48 = [PROD/Minutes Played]*48

 

P48 = PROD48 – MATE48

 

Here are the values for MATE48 in 2006-07

Table Thirteen

Value of MATE48 in 2006-07

Team

MATE48

Atlanta

-0.00658

Boston

-0.00603

Charlotte

0.00367

Chicago

0.00790

Cleveland

-0.00316

Dallas

-0.00432

Denver

0.01220

Detroit

0.00498

Golden State

0.01531

Houston

-0.00390

Indiana

-0.00023

LA Clippers

0.00553

LA Lakers

0.00641

Memphis

-0.00297

Miami

-0.00080

Milwaukee

-0.00497

Minnesota

0.00251

New Jersey

0.00720

New Orleans

-0.01261

New York

-0.01705

Orlando

-0.00990

Philadelphia

-0.00373

Phoenix

0.02064

Portland

-0.01290

Sacramento

-0.00873

San Antonio

0.00577

Seattle

-0.00575

Toronto

0.00235

Utah

0.01373

Washington

-0.00457

 

Note: For 2006-07, the average value for blocked shots and assists per 48 minutes was 0.11004.

The average value for MATE48, in absolute terms, was .00723.

 

Step Three:      Adjust for DEFTM48 and calculate Adj. P48

 

Adj. P48 = P48 – DEFTM48

 

Here are the values for DEFTM48 in 2006-07

 

Table Fourteen

Value of DEFTM48 in 2006-07

Team

DEFTM48

Atlanta

-0.004838

Boston

-0.011380

Charlotte

-0.008978

Chicago

-0.025093

Cleveland

-0.020608

Dallas

-0.016380

Denver

0.019057

Detroit

-0.015784

Golden State

0.011894

Houston

-0.008566

Indiana

-0.014493

LA Clippers

-0.000473

LA Lakers

0.006892

Memphis

0.027201

Miami

0.007541

Milwaukee

0.016586

Minnesota

0.006528

New Jersey

-0.002011

New Orleans

0.008044

New York

0.012923

Orlando

-0.026345

Philadelphia

0.001006

Phoenix

0.014891

Portland

-0.002966

Sacramento

0.012344

San Antonio

-0.014198

Seattle

0.016748

Toronto

0.010224

Utah

-0.016428

Washington

0.016661

 

Note: For 2006-07, the average value for the Team Defensive Adjustment was -0.1885.

The average value for DEFTM48, in absolute terms, was 0.01257.

 

Step Four:        Adjust for position played

 

Relative Adj. P48 = Adj. P48 – League Average Adj. P48

 

Here is the average Adj. P48 at each position in 2006-07.  Notice that relative to 1977-78, big men are less productive and guards and small forwards are now more productive. 

 

Table Fifteen

Value of Adj. P48 Across Positions

Position

Average Adj P48

Centers and Power Forwards

0.37593

Small Forwards

0.26309

Guards

0.23884

 

 

Step Five:         Calculate WP48 and Wins Produced

 

WP48 = Relative Adj. P48 + 0.09910

 

Wins Produced = WP48/48 * Minutes Played

 

Here is the accuracy of Wins Produced for the 2006-07 Season

 

Table Sixteen

Reviewing the Accuracy of Wins Produced in 2006-07

Team

Actual

Wins

Summation of

Wins Produced

Difference in

Absolute Terms

Atlanta

30

28.3

1.7

Boston

24

31.8

7.8

Charlotte

33

31.2

1.8

Chicago

49

54.3

5.3

Cleveland

50

51.3

1.3

Dallas

67

60.2

6.8

Denver

45

45.2

0.2

Detroit

53

52.3

0.7

Golden State

42

39.9

2.1

Houston

52

54.0

2.0

Indiana

35

34.3

0.7

LA Clippers

40

39.5

0.5

LA Lakers

42

41.2

0.8

Memphis

22

27.5

5.5