Projected Wins Adjusted to Match the NBA’s Zero Sum Reality

I mentioned before that my initial run through of the projected wins for each team overestimated wins, due to the xRAPM projections combined with my minutes projections projecting league average xRAPM to be +1.11 per game, which is impossible. The average total xRAPM per team across the league must, by definition, equal zero. Any team’s positive xRAPM- because it is a plus-minus statistic- comes at the expense of its opponents’ xRAPM, so across the 30 teams, things must sum to 0. In order to account for this, I adjusted the net rating of each team to reflect the +1.11 initial average and reset the league average to 0. This also results in team wins summing properly to the 1230 available in any given year. Below is a chart with the adjusted net ratings and win totals. After that, those win totals are placed into the context of each conference, so you can see which teams project to be in the playoffs.

Projected Eastern Conference Standings

1. Miami — 57–25

2. Brooklyn — 55–27

3. Chicago — 53–29

4. Indiana — 49–33

5. New York — 44–38

6. Atlanta — 43–39

7. Toronto — 39–43

8. Detroit — 39–43

— — — — — — — — — — — — — — — — — — — — — — — — — — —

9. Cleveland — 38–44

10. Washington — 36–46

11. Milwaukee — 33–49

12. Philadelphia — 32–50

13. Charlotte — 32–50

14. Boston — 27–55

15. Orlando — 25–57

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Projected Western Conference Standings

1. Oklahoma City — 57–25

2. Houston — 56–26

3. Los Angeles Clippers — 53–29

4. Memphis — 51–31

5. Spurs — 50–32

6. Golden State — 47–35

7. Minnesota — 42–40

8. Dallas — 42–40

— — — — — — — — — — — — — — — — — — — — — — — — — — —

9. New Orleans — 39–43

10. Denver — 38–44

11. Portland — 37–45

12. Utah — 33–49

13. Sacramento — 32–50

14. Los Angeles Lakers — 28–54

15. Phoenix — 26–56

__________________________________

I think these results pass the smell test, with the notable exception of Philadelphia inexplicably projecting to win 32 games. Let me know what you think. I’ll be continuing to post team breakdowns, with the unadjusted numbers (all of my graphics showing the numbers are already done and it would be a pain to redo them all), though I’ll be sure to make note of the need to adjust the numbers to account for the +1.11 average in those future posts.

Image from Keith Allison via Flickr.

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