Postseason Odds, Forecast version

Playing the rest of the season a million times

with some help from my forecasts

by Clay Davenport

See the original version of this report, based entirely on real data (no projections).

*** Now with 2! 2! 2 wild cards per league ***

Generated Tue Sep 1 08:01:21 EDT 2015


Average wins by position in AL East:  91.2 87.4 81.1 78.3 75.5
AL East           W    L    Pct3  Avg W  Avg L  Champions  Wild Card   Playoffs
Blue Jays         74   57   .531   90.2   71.8   65.69517   32.75232   98.44749
Yankees           72   58   .518   88.4   73.6   34.04475   60.16215   94.20691
Rays              65   66   .487   79.7   82.3     .19091    6.39598    6.58688
Orioles           63   68   .515   78.3   83.7     .05663    2.46460    2.52122
Red Sox           61   70   .518   77.0   85.0     .01255     .93024     .94279

Average wins by position in AL Central:  96.6 83.4 80.3 77.6 74.4
AL Central        W    L    Pct3  Avg W  Avg L  Champions  Wild Card   Playoffs
Royals            80   50   .523   96.6   65.4   99.93542     .06181   99.99722
Twins             67   63   .487   82.2   79.8     .05198   26.07482   26.12681
Indians           64   66   .512   80.4   81.6     .01192   10.71316   10.72507
White Sox         61   68   .507   77.6   84.4     .00065    1.86900    1.86965
Tigers            60   70   .489   75.5   86.5     .00003     .38957     .38960

Average wins by position in AL west:  90.1 84.1 80.1 75.7 71.9
AL West           W    L    Pct3  Avg W  Avg L  Champions  Wild Card   Playoffs
Astros            73   59   .561   89.9   72.1   90.92005    6.88667   97.80672
Rangers           68   62   .497   83.7   78.3    7.97308   40.05053   48.02361
Angels            65   66   .512   80.5   81.5    1.09637   11.02236   12.11872
Mariners          61   71   .483   75.3   86.7     .01010     .21598     .22608
Athletics         58   74   .502   72.7   89.3     .00040     .01081     .01121

Average wins by AL First Wild Card:  87.8
Average wins by AL Second Wild Card:  84.8

Average wins by position in NL East:  89.6 85.1 70.0 66.9 62.8
NL East           W    L    Pct3  Avg W  Avg L  Champions  Wild Card   Playoffs
Mets              73   58   .498   89.0   73.0   77.78410    1.20647   78.99057
Nationals         66   64   .579   85.7   76.3   22.21585    2.46397   24.67982
Braves            54   77   .447   68.1   93.9     .00005     .00000     .00005
Marlins           53   79   .490   68.3   93.7     .00000     .00000     .00000
Phillies          52   80   .381   63.3   98.7     .00000     .00000     .00000

Average wins by position in NL Central:  102.4 96.9 91.7 70.4 66.7
NL Central        W    L    Pct3  Avg W  Avg L  Champions  Wild Card   Playoffs
Cardinals         85   46   .548  102.2   59.8   90.37770    9.62210   99.99980
Pirates           79   50   .528   96.8   66.2    9.10295   90.67755   99.78050
Cubs              74   56   .536   92.1   70.9     .51935   92.99215   93.51150
Brewers           55   75   .461   69.2   92.8     .00000     .00000     .00000
Reds              54   76   .448   68.0   94.0     .00000     .00000     .00000

Average wins by position in NL West:  91.6 84.7 79.8 76.3 68.3
NL West           W    L    Pct3  Avg W  Avg L  Champions  Wild Card   Playoffs
Dodgers           73   57   .562   91.5   70.5   94.01378     .53872   94.55250
Giants            69   62   .487   84.6   77.4    5.79826    2.45381    8.25206
Padres            64   67   .466   79.0   83.0     .14866     .03358     .18224
Diamondbacks      63   68   .471   77.4   84.6     .03931     .01166     .05096
Rockies           53   76   .460   68.3   93.7     .00000     .00000     .00000

Average wins by NL First Wild Card:  96.3
Average wins by NL Second Wild Card:  91.2

As the title says, the post-season odds report was compiled by running a Monte Carlo simulation of the rest of the season one million times. Current wins, losses and expected winning percentages are taken from the Adjusted Standings Report.

Expected winning percentages (EWP) is being driven entirely by the projections of player performance on our depth charts. The performances of every player on a team are combined to derive total team runs scored and allowed, which are averaged and normalized on a league basis, and used to calculate a won/lost record. The disadvantage of this approach is that the team's rating is entirely based on a projection of player performance. The advantage is that it can immediately respond to changes in the team's lineup, due to injury or trade. However, we still allow for uncertainty in the EWP by sampling a normal distribution centered on the EWP for each "seasonal" run. To simulate the normal 4% home-field advantage, the home team gets a .020 point bonus, while the visitors take a 0.020 penalty. The likelihood of winning each game is determined by the log5 method.

W and L are the team's wins and losses through yesterday's games.

Pct3 is the expected winning percentage, taken from W3 and L3, with the regression-to-mean component.

Avg W and Avg L are the average number of wins and losses each team finishes over the million season iterations.

Champions is how often, in percentage terms, this team won the championship of their division. Ties are not broken, but credited as 0.5 championships apiece (for a two-way tie), .333 apiece for a three-way tie, .25 for four-way, etc. This is why the final decimal place is not an error!

Wild Card is how often, in percentage terms, this team won the wild card. As with championships, ties are not broken, but apportioned among the tied teams.

Playoffs is how often, in percentage terms, the team either wins the division or the wild card.