2018-19 team win projection contest

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sndesai1
Posts: 131
Joined: Fri Mar 08, 2013 10:00 pm

Re: 2018-19 team win projection contest

Post by sndesai1 » Sat Nov 03, 2018 6:01 am

Mike G wrote:
Sat Nov 03, 2018 4:13 am
sndesai1 wrote:
Sat Nov 03, 2018 1:33 am
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
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Location: Asheville, NC

Re: 2018-19 team win projection contest

Post by Mike G » Sat Nov 03, 2018 2:37 pm

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.

Code: Select all

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
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Location: Asheville, NC

Re: 2018-19 team win projection contest

Post by Mike G » Mon Nov 05, 2018 11:28 am

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

Code: Select all

. 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
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Location: Asheville, NC

Re: 2018-19 team win projection contest

Post by Mike G » Wed Nov 07, 2018 2:04 pm

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

Code: Select all

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
Posts: 101
Joined: Mon Sep 29, 2014 4:54 am

Re: 2018-19 team win projection contest

Post by Rd11490 » Wed Nov 07, 2018 5:55 pm

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
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Location: Asheville, NC

Re: 2018-19 team win projection contest

Post by Mike G » Wed Nov 07, 2018 11:20 pm

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
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Contact:

Re: 2018-19 team win projection contest

Post by caliban » Sat Nov 10, 2018 2:29 pm

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.

Image

Mike G
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Location: Asheville, NC

Re: 2018-19 team win projection contest

Post by Mike G » Mon Nov 12, 2018 10:25 am

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

Code: Select all

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:

Code: Select all

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

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