2018-19 team win projection contest

[sndesai1]

bk-ref projections are ok for regular season wins after a couple months, but there's no informed prior. all that it really seems to use is a team's current srs regressed towards 0 and the remaining schedule, which leads to odd projections early on.

At what point in the season is current SRS + remaining schedule actually a better predictor than what you thought before the season started? Could we be there already?

I stole your spreadsheet. Thanks! Is Pinnacle what we could call Vegas?

i feel like somebody here has done some analysis re: how long into a season it takes various stats such as net rating to stabilize...maybe it was on nylon calculus

i don't think we are at the point yet where current season srs is more valuable than preseason expectations. bk-ref is still regressing a lot (it just seems to be towards 0 for every team instead of towards something informed). i'd guess between 20-30 games is the point at which current season results should have a 50% weight in an evaluation of the remainder or the regular season. once this season comes to a close, i'll probably take a look at this since i'll already have everything compiled

re: pinnacle - yes those are the betting numbers we're using for comparison this year (just to be clear, it's hq is not anywhere near vegas). i grabbed them from shadow's post here: http://apbr.org/metrics/viewtopic.php?f ... =30#p33145

[Mike G]

So your early projections had teeny-tiny errors based on the supposition that the Rockets will pick it up, the Bucks will cool off, etc.
Going just by to-date performance -- and daily adjustments to SOS, which buffets the SRS's noticeably -- these errors will diminish as the season goes along. The range top-to-bottom will also tighten.

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avg abs err   rmse      avg abs err   rmse
KPel   5.94   7.83      bbst   6.92   8.54
shad   6.25   8.15      gold   7.09   8.90
vegas  6.41   8.41      Jinx   7.12   9.01
AnJo   6.45   8.22      Crow   7.34   9.72
cali   6.60   8.69      sndi   7.41   9.30
RyRi   6.62   8.65      538_   7.47   9.46
J-TF   6.74   9.87      kmed   8.42  10.61
trzu   6.74   8.16      Cica   8.55  10.87
emin   6.77   8.75      Rd11   9.18  11.18

Vegas is holding its own now; last year (most years?) they are middling here.

[Mike G]

Over- and under-achieving teams to date, relative to the predictions entered

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. over   avg  proj       under    avg proj
20  Sac   23   42      -21   Hou   57   36
13  Mil   48   61      -11   Phl   52   41
11  NYK   25   36      -11   Was   45   34
11  Cha   38   49      -11   Uta   54   43
10  Por   40   51       -9   Min   45   36
9   LAC   38   47       -8   Cle   32   24
8   Mem   33   41       -7   GSW   64   57
5   Chi   26   31       -5   LAL   44   39

Current projections are according to b-r.com, with serious regression to .500
avg is the average wins predicted by 16 individuals

[Mike G]

The order has hardly changed, but errors have worsened, and Pelton has extended his lead.

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avg abs err   rmse      avg abs err   rmse
KPel   6.09   7.86      emin   7.12   8.65
shad   6.60   8.09      gold   7.16   8.78
AnJo   6.64   8.16      Jinx   7.22   8.84
J-TF   6.77   9.70      Crow   7.46   9.48
vegas  6.81   8.30      sndi   7.64   9.19
cali   6.83   8.47      538_   7.72   9.35
RyRi   6.88   8.57      Cica   8.72  10.91
trzu   6.94   8.04      kmed   8.73  10.45
bbst   7.10   8.54      Rd11   9.40  11.13

[Rd11490]

I knew my projections were off (way to long at the tails), but I didn't expect to be this bad. Kings and cavs are killing me.

[Mike G]

Last year on this date, 4 contestants were looking worse in avg error.
Eminence was 15th at MAE = 9.1, and he went on to win it.
viewtopic.php?f=2&t=9403&hilit=prediction&start=75

[caliban]

PM me if I've fat fingered your entry. Open png in new tab for better resolution.

10+ games in. Projections courtesy of

TeamRankings, Rankings & Projections Summary
FiveThirtyEight, NBA Predictions
bbstats, Luck-Adjusted Win Prediction

East projected to win 590 games. 615 being equal.

[Mike G]

Based only on current season as projected by b-r.com

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avg abs err   rmse      avg abs err   rmse
KPel   6.17   8.23      Jinx   7.14   8.97
AnJo   6.66   8.36      emin   7.19   8.78
shad   6.68   8.34      gold   7.20   8.94
vegas  6.80   8.46      Crow   7.36   9.34
trzu   6.80   8.02      sndi   7.42   9.28
J-TF   6.83   9.94      538_   7.80   9.46
RyRi   6.90   8.78      kmed   8.65  10.45
cali   6.93   8.60      Cica   8.69  11.08
bbst   6.97   8.69      Rd11   9.40  11.15

11-14, some nice improvements in 2 days:

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avg abs err   rmse      avg abs err   rmse
KPel   5.80   7.86      Jinx   6.80   8.56
AnJo   6.03   7.92      J-TF   6.82   9.63
shad   6.18   7.90      Crow   6.89   8.85
trzu   6.41   7.56      gold   6.95   8.62
vegas  6.41   8.05      sndi   7.07   8.87
RyRi   6.45   8.34      538_   7.40   9.07
bbst   6.54   8.29      kmed   8.24  10.06
cali   6.61   8.16      Cica   8.25  10.45
emin   6.69   8.15      Rd11   9.13  10.75

Pelton era over?

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avg abs err   rmse      avg abs err   rmse
AnJo   5.71   7.72      emin   6.70   8.24
KPel   5.71   7.78      Jinx   6.72   8.57
shad   5.94   7.71      J-TF   6.83   9.60
vegas  6.17   7.81      sndi   7.06   8.86
trzu   6.24   7.47      538_   7.09   8.96
RyRi   6.27   8.22      Crow   7.11   9.02
bbst   6.41   8.22      kmed   8.08   9.98
cali   6.44   8.13      Cica   8.62  10.66
gold   6.64   8.56      Rd11   9.22  11.09

One day later (11-16), nope:

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avg abs err   rmse      avg abs err   rmse
KPel   5.81   7.77      gold   6.73   8.59
AnJo   5.89   7.77      emin   6.74   8.07
shad   6.04   7.66      Jinx   6.81   8.57
vegas  6.11   7.69      sndi   7.10   8.84
trzu   6.40   7.46      538_   7.18   8.98
RyRi   6.43   8.20      Crow   7.25   9.00
bbst   6.52   8.26      kmed   8.16   9.98
cali   6.61   8.13      Cica   8.79  10.63
J-TF   6.64   9.41      Rd11   9.13  11.12

[Mike G]

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avg abs err   rmse      avg abs err   rmse
AnJo   5.97   7.67      Jinx   6.73   8.51
shad   6.07   7.62      J-TF   6.76   9.28
vegas  6.08   7.70      gold   6.92   8.54
KPel   6.09   7.77      sndi   6.95   8.76
trzu   6.36   7.34      Crow   7.17   8.91
cali   6.45   8.09      538_   7.27   8.94
RyRi   6.46   8.13      kmed   8.19   9.87
emin   6.68   7.98      Cica   8.64  10.43
bbst   6.70   8.20      Rd11   9.02  10.97

The West continues to dominate the East in inter-conference games.
Those who predicted this are somehow near the bottom.

[sndesai1]

Thanksgiving Update

https://docs.google.com/spreadsheets/d/ ... IwFv_wPes/

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Rank	Entry			MAE
1	tarrazu			3.70
2	bbstats			3.78
3	Pinnacle (No Juice)	3.79		
4	Average			3.97
5	shadow			3.99
6	caliban			4.00
7	sndesai1		4.04	
8	ESPN BPI		4.06	
9	eminence		4.07	
10	RyanRiot		4.08	
11	Jinxed			4.10
12	Andrew Johnson		4.11	
13	jgoldstein34		4.17	
14	Kevin Pelton		4.27	
15	ESPN Summer Forecast	4.29		
16	538			4.35
17	Jrue-Tang Forever	4.49		
18	kmedved			4.71
19	Crow			4.99
20	Pyth + Regression	5.74		
21	Rd11490			5.85
22	Cicada			6.20

[Mike G]

Based on the season in progress;

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avg abs err   rmse      avg abs err   rmse
KPel   6.32   8.17      gold   7.11   8.95
AnJo   6.51   8.07      emin   7.27   8.66
shad   6.62   8.13      sndi   7.33   9.15
trzu   6.64   7.86      J-TF   7.33   9.63
vegas  6.65   8.21      538_   7.55   9.34
cali   6.73   8.60      Crow   7.73   9.69
RyRi   6.75   8.56      kmed   8.43  10.38
Jinx   7.02   8.94      Cica   9.10  11.01
bbst   7.09   8.53      Rd11   9.21  11.38

12-01: New undisputed leader

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avg abs err   rmse      avg abs err   rmse
trzu   6.29   7.52      J-TF   6.99   9.44
KPel   6.44   7.89      Jinx   7.08   8.72
AnJo   6.62   7.96      emin   7.10   8.40
gold   6.73   8.49      sndi   7.24   8.93
bbst   6.73   8.09      538_   7.48   9.04
shad   6.75   8.01      Crow   7.85   9.52
cali   6.77   8.44      kmed   7.93   9.85
vegas  6.90   8.13      Cica   8.92  10.74
RyRi   6.95   8.33      Rd11   9.19  11.12

12-05 Pulling away:

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avg abs err   rmse      avg abs err   rmse
trzu   6.16   7.53      J-TF   6.99   9.48
KPel   6.53   7.95      emin   7.03   8.39
gold   6.69   8.50      Jinx   7.11   8.76
bbst   6.69   8.06      sndi   7.17   8.86
shad   6.73   8.03      538_   7.46   9.02
cali   6.74   8.54      kmed   7.57   9.84
AnJo   6.75   7.99      Crow   7.84   9.61
vegas  6.86   8.15      Cica   8.89  10.74
RyRi   6.94   8.34      Rd11   8.90  11.20

[Mike G]

Major improvements at last:

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avg abs err   rmse      avg abs err   rmse
trzu   5.54   6.96      emin   6.39   7.93
KPel   6.01   7.45      Jinx   6.49   8.23
shad   6.04   7.54      sndi   6.66   8.41
bbst   6.07   7.53      J-TF   6.67   9.40
AnJo   6.23   7.63      538_   6.89   8.57
vegas  6.23   7.70      kmed   7.20   9.39
cali   6.25   8.12      Crow   7.21   9.11
RyRi   6.29   7.92      Rd11   8.21  10.55
gold   6.38   8.13      Cica   8.25  10.26

12/13 update

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avg abs err   rmse      avg abs err   rmse
trzu   5.79   7.18      Jinx   6.49   8.35
emin   6.11   7.91      gold   6.53   8.29
shad   6.14   7.68      sndi   6.59   8.45
bbst   6.17   7.69      J-TF   6.68   9.52
KPel   6.21   7.74      538_   7.05   8.76
vegas  6.21   7.77      Crow   7.29   9.21
cali   6.31   8.28      kmed   7.30   9.63
AnJo   6.35   7.83      Rd11   8.11  10.68
RyRi   6.40   8.10      Cica   8.33  10.37

[sndesai1]

the various projections are becoming pretty consistent now - bk-ref still has a few outliers such as gsw/hou where the exclusion of information outside this season makes them a little more pessimistic than average
538 also has a few divergent expectations relative to the average, though not to the same extent

[Mike G]

These 18 entries now show avg error of 6.29, an improvement of 1.00 since end of Nov.

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avg abs err   rmse      avg abs err   rmse
trzu   5.35   6.62      Jinx   5.99   7.75
vegas  5.67   6.99      J-TF   6.13   8.74
shad   5.76   6.88      sndi   6.23   7.88
AnJo   5.80   7.08      gold   6.26   7.78
KPel   5.82   6.99      538_   6.66   8.10
cali   5.82   7.57      Crow   7.05   8.86
emin   5.90   7.36      kmed   7.18   9.08
RyRi   5.91   7.37      Cica   7.79   9.67
bbst   5.97   7.21      Rd11   7.86  10.27

The avg is dragged down by the bottom 1/4; but in the last 3 weeks the spread (top to bottom) has also shrunk from 3.13 to 2.51

[Rd11490]

Minnesota, Sacramento and Cleveland are absolutely ruining me >.<