Re: 2024-25 team win projection contest
Posted: Fri Mar 07, 2025 1:24 am
Caught ESPN experts, at least for a moment. Will see if it lasts. Pretty close to Vegas.
Analysis of basketball through objective evidence
http://www.apbr.org/metrics/
Code: Select all
. avg err rmse r^2 . avg err rmse r^2
TmTj 6.76 9.0 .50 emin 7.56 9.8 .44
dtka 6.79 8.9 .51 eExp 7.58 9.8 .51
avgA 6.92 9.2 .47 Crow 7.59 9.7 .46
medi 7.21 10.1 .42 WShr 7.77 9.7 .41
KPel 7.24 8.8 .57 24pr 7.99 10.4 .32
bpmW 7.27 9.2 .47 eWin 8.50 10.8 .27
DQin 7.32 9.4 .47 24py 8.52 11.5 .32
vegas 7.43 9.7 .44 perW 8.74 11.0 .24
. bmgm 9.03 11.9 .33
Code: Select all
e = .10 e = .20 e = .50
3.89 Crow 4.72 medi 5.52 dtka
4.43 medi 4.72 dtka 5.63 TmTj
4.45 dtka 4.86 Crow 5.63 medi
4.80 TmTj 5.00 TmTj 6.13 bpmW
5.04 bpmW 5.33 bpmW 6.16 vegas
e = 1.12 e = 1.75 e = 5.00
7.04 TmTj 8.39 dtka 11.8 KPel
7.07 dtka 8.46 KPel 12.3 dtka
7.46 KPel 8.46 TmTj 13.3 bpmW
7.52 bpmW 8.75 bpmW 13.4 WShr
7.59 medi 8.94 DQin 13.6 TmTj
Code: Select all
. avg err rmse r^2 . avg err rmse r^2
TmTj 6.76 9.0 .50 emin 7.60 9.9 .44
dtka 6.77 8.85 .51 eExp 7.62 9.8 .51
avgA 6.87 9.2 .47 Crow 7.64 9.7 .46
medi 7.21 10.2 .42 WShr 7.71 9.7 .41
bpmW 7.25 9.2 .47 24pr 7.94 10.4 .32
DQin 7.30 9.4 .47 eWin 8.49 10.8 .27
KPel 7.34 8.86 .57 24py 8.51 11.5 .32
vegas 7.54 9.7 .44 perW 8.84 11.0 .24
. bmgm 9.04 11.9 .33
The projections are built mostly from the player level using CraftedPM (Jimmy Butler is good!), but we also use their season net rating up to this point, as well as their net rating in their last ten games. There's quite a bit more to it, but that's the quick and dirty."So the Dubs at 55% for the season are expected to win 70% the rest of the way?
Is there a recency factor affecting their season record?
Any reason to not include a decimal place in the forecast?
Is it fair that Den, Uta, Chi, and Det get 83 games?"
That's what b-r.com shows, even knowing that no team will end up with a fraction of a win.Do you think we should show a decimal place? I like the clean look aesthetically, but the decimal does provide a more granular projection.
This is a great question, and it's worth questioning why RMSE (e = 2) is the default error metric in so many contests.
RMSE vs. MAE
RMSE (Root Mean Squared Error, e = 2): Penalizes larger errors more heavily than smaller ones. This is useful when you want to emphasize avoiding big misses.
MAE (Mean Absolute Error, e = 1): Treats all errors equally, making it easier to interpret and explain, but less sensitive to outliers.
The Case for e ≠ 2
You're right to be skeptical of RMSE's dominance. The choice of exponent (e) determines how harshly large errors are punished. If you set e < 2, you're reducing the penalty for big misses, while e > 2 makes the metric even more extreme.
Something like e = 1.5 or 1.75 could be an interesting compromise—more punishing than MAE but without RMSE’s harsh treatment of big errors. This might better reflect the importance of getting all teams reasonably close rather than just avoiding a few disasters.
What Matters for the Contest?
For a win projection contest, should a single bad miss (like predicting 30 wins for a team that gets 50) outweigh a handful of small misses? If the goal is consistency across all teams, a lower exponent (closer to 1) makes sense. If punishing big misses is important, e = 2 or higher is justifiable.
Code: Select all
. avg err rmse r^2 . avg err rmse r^2
TmTj 6.95 9.2 .49 WShr 7.70 9.7 .41
dtka 6.95 8.9 .50 vegas 7.70 9.8 .44
avgA 7.05 9.3 .46 Crow 7.74 9.8 .45
bpmW 7.25 9.3 .46 24pr 7.96 10.4 .32
medi 7.34 10.2 .42 24py 8.59 11.6 .32
DQin 7.46 9.6 .46 eWin 8.61 10.9 .26
KPel 7.54 9.0 .57 perW 8.97 11.1 .23
eExp 7.69 9.9 .49 bmgm 9.20 12.0 .32
emin 7.69 9.9 .43
Code: Select all
e = .20 e = .50 e = .92 e = 1.80 e = 6.00
4.89 medi 5.74 dtka 6.760 TmTj 8.59 dtka 12.6 KPel
4.98 dtka 5.78 TmTj 6.765 dtka 8.75 TmTj 13.1 dtka
5.09 TmTj 5.79 medi 7.07 bpmW 8.76 KPel 14.4 bpmW
5.20 bpmW 6.03 bpmW 7.09 medi 8.90 bpmW 14.5 WShr
5.57 emin 6.33 DQin 7.28 DQin 9.17 DQin 14.7 DQin
5.58 eExp 6.40 emin 7.40 KPel 9.35 WShr 14.7 TmTj
5.65 DQin 6.40 eExp 7.49 eExp 9.40 Crow 14.9 eExp
Code: Select all
. avg err rmse r^2 avg err rmse r^2
dtka 7.02 9.0 .50 WShr 7.78 9.8 .40
TmTj 7.05 9.3 .48 Crow 7.79 9.9 .45
avgA 7.13 9.4 .46 vegas 7.81 9.9 .43
medi 7.36 10.3 .41 24pr 7.97 10.5 .32
bpmW 7.38 9.4 .46 24py 8.61 11.6 .32
DQin 7.48 9.7 .45 eWin 8.74 11.0 .25
KPel 7.56 9.1 .56 perW 9.07 11.2 .23
eExp 7.74 10.0 .48 bmgm 9.21 12.0 .32
emin 7.76 10.0 .43
Code: Select all
e = .10 e = .25 e = .54 e = 1.80 e = 6.00
4.05 DQin 5.08 medi 5.88 dtka 8.67 dtka 12.8 KPel
4.15 KPel 5.09 dtka 5.94 TmTj 8.86 KPel 13.2 dtka
4.66 dtka 5.19 TmTj 5.94 medi 8.86 TmTj 14.6 bpmW
4.66 medi 5.27 DQin 6.28 bpmW 9.00 bpmW 14.6 WShr
4.79 TmTj 5.44 KPel 6.30 DQin 9.26 DQin 14.8 DQin
5.02 bpmW 5.48 bpmW 6.50 KPel 9.42 WShr 14.9 TmTj
5.29 emin 5.73 emin 6.55 emin 9.48 Crow 15.1 eExp
Crow wrote: ↑Fri Feb 28, 2025 6:43 pm A primary reason LEBRON and DARKO projections weren't included is because they were not entered here by authors, checked or found.
If projections were made and published before season, please provide link.
Last season, Darko finished 13th of 20 listings, LeBron 18th.
viewtopic.php?t=10034&start=165
4th and 5th in 2022-23:
viewtopic.php?t=9946&start=165#p39853
Darko 1st in expanded check for 2021-22, LeBron 19th of 30:
viewtopic.php?t=9903&start=105
3+ year averages might be interesting. There is some "randomness" involved I'd say.
'20-21: viewtopic.php?t=9842&start=105
'19-20 (my most recent win):
viewtopic.php?t=9715&start=150