When Dave first came up with the Wins Produced formula, his unit of measure made a lot of sense. When we want to examine a player’s contribution over a whole season, we look at wins. But the world has changed and we are now able to give you game by game stats. In a given game only one win is at stake. It’s confusing to understand exactly what a portion of a win means for just one game.
The Wins Produced formula is based on point differential. Basically, if we look at the number of points a team gets on offense versus the number of points a team allows on defense we can estimate how many wins they earn. When we put box score statistics in terms of points (roughly one possession is worth a point) we can get a good estimate of how many points a given player earns their team. If this sounds like old news…well it is. Arturo gave us this formula last year! We debated a little bit on the name to use but settled on Points over Par (PoP). An average or “par player” would earn us exactly 0.0 points per 48 minutes played. If the NBA allowed ties and counted them as half a win, we can can see a team of “par players” would earn 41 wins in a season. Players above par gain their team points, and players below par lose points. The formula for Points over Par per 48 (POP/48) is:
(WP48 - 0.099) * 31.1
How about a quick demonstration staring the Denver Nuggets on February 29th
Kenneth Faried’s time on the court was worth an extra 10.6 points for the Denver Nuggets. Compare this with Corey Brewer, who cost the Nuggets 7 points. Additionally, had Faried played the whole game at his production he would have earned his team a 29.3 point edge. We can see in the end that the Denver Nuggets combined for a 9.2 margin, which is consistent with what we saw for the night — Denver defeated Portland 104 to 95.
This can also be useful in looking at players over the whole season. Here’s a small sample of NBA players:
Having LeBron James on your team is like going in with a 7 point edge. Going in with Glen Davis? It’s spotting the opponent 3 points a game. This season Emeka Okafor is playing as the very epitome of a “par player”. He won’t gain you any points, but he won’t cost you any either.
One last note. It should be pretty easy to note that a player can have a positive Wins Produced while having a negative Points over Par. This is because even teams that regularly get outscored are expected to win some games. For instance, the Phoenix Suns are getting outscored by around 1.7 points a game this season but have still won 17 games. Similarly, a player can still give up points and still contribute. The point is if they play an opponent with more Players over Par their contribution will not be enough. Luckily in the NBA it is rare to play an opponent of all players performing at or above par for a given game.
Hopefully this new unit of measure will help to understand exactly how players are contributing on a game by game basis. We’ll be keeping them up to date for the season at Nerd Numbers
-Arturo and Dre