The NBA tracks a variety of statistics to measure a player’s performance on the court. NBA fans are familiar with points scored, rebounds, steals, assists, turnovers, blocked shots, etc… The difficulty with these statistics is that some players excel at some aspects of the game, but not at others. And what we want to know when confronted with players with different skills is how each player impacts the final outcome we observe on the court.
The approach we took in The Wages of Wins is simply to utilize regression analysis – a common technique in economics – to determine the relative impact of each statistics on team wins. We had three objectives in constructing our model. Ultimately we wanted a measure that was simple, complete, and accurate. In the end, we think each of these objectives was met. The Wins Produced model is not hard to understand, it incorporates each of the statistics tracked for individual players, and it connects accurately to team wins.
With the Wins Produced model one can begin with a player’s statistics – his points, shot attempts, rebounds, steals, turnovers, etc.. – and translate these into how many wins those statistics creates. And with this measure we can tell three basic stories about talent evaluation in the NBA.
- Players who do many things well – like Michael Jordan, LeBron James, Shaquille O’Neal, Tim Duncan, and Kevin Garnett – are very productive players, just like most people believe.
- Players who only score, though, or have deficiencies in their game (i.e. low shooting efficiency, high turnover rates) – like Allen Iverson, Antoine Walker, and Carmelo Anthony – are not as productive as people believe.
- Players who are prolific rebounders – like Dennis Rodman, Ben Wallace, and Marcus Camby – are more productive than people tend to believe.
Now it is important to understand what Wins Produced says, and what it doesn’t say. Specifically, Wins Produced tells us how productive a player has been. It does not, though, tell us why that player is productive. This is a point we made in the following excerpt from The Wages of Wins.
p. 125 in The Wages of Wins
One cannot end the analysis when one has measured the value of player performance. Knowing the value of each player is only the starting point of analysis. The next step is determining why the player is productive or unproductive. In our view, this is where coaching should begin. We think we can offer a reasonable measure of a player’s productivity. Although we have offered some insights into why players are productive, ultimately this question can only be answered by additional scrutiny into the construction of a team and the roles a player plays on the floor.
The Wins Produced measure does not replace the insights of coaching and NBA analysts. What it does is correct flaws in the evaluation of talent in The Association. Players who do not shoot efficiently, or turn the ball over frequently, do not help a team win many games. Players who can accumulate large numbers of rebounds can indeed have a large impact on final outcomes. Of course, why a player shoots inefficiently, commits turnovers, or rebounds well, is not a question Wins Produced will answer.
In The Wages of Wins we do explore some factors that cause players to perform better or worse. For example, we spend some time discussing how a player with more productive teammates will tend to be less productive. Or low levels of roster turnover – specifically, keeping a team together – will cause a player’s performance to improve.
And we did consider other issues with respect to player performance – and if you wish to see these please read the book. Or just wait. At the rate we’re going, we might eventually get the entire book on-line, one excerpt at a time.
– DJ
If you see an investigative article of Michael Wilczynski at 82games.com that relate extreme individual performance and winning games, you can see that rebounds are not so determinant and FG´s yes. I know that it´s not true at all, and I can´t find a way to refute that, but it says something.
But you can also see that two points (a score) is just a little bit more determinant than one rebound (maybe Tendex formulas are not so lost). Rodman looked good here, but I think is because the team.
The surprise?….assists. Assists were more important than rebounds, points, blocks, steals, etc.
The two stats most important?…FG% and Assists.
The most winnable combination?… a good inside scorer and a good point guard.
Ah! …some people think those formulas overrate turnovers..
but, yes, turnovers were a big weight in losing games, just a little less than a very bad FG%.
One on one defense stats, of course, weighted less than everything, but not too much. I think team defense makes up that (all formulas are weak in this area).
All that was based on 10 years stats (extreme performances games). I supose your WinProduced calculus had a wider universe of years and ordinary games.
P.D. By the way, wich team do you think will win the finals, and why?