Postseason Odds

Playing the rest of the season a million times

by Clay Davenport

See the Forecast-adjusted version of this report.

Generated Mon May 21 08:01:47 EDT 2018


Average wins by position in AL East:  105.0 95.6 82.9 72.0 60.4
AL East           W    L    Pct3  Avg W  Avg L  Champions  Wild Card   Playoffs      1D Change 7D Change
Red Sox           32   15   .573   97.7   64.3   32.01868   56.46394   88.48262         .90157    .07746
Yankees           30   13   .607  102.3   58.7   66.50630   29.52510   96.03140        1.80770    .98582
Rays              22   23   .518   82.2   79.8    1.42253   15.87488   17.29741       -5.49652   5.87206
Blue Jays         22   25   .450   72.1   89.9     .05203    1.43585    1.48789       -0.79646  -3.72090
Orioles           14   32   .423   61.8  100.2     .00045     .03954     .03999       -0.02622  -0.16906

Average wins by position in AL Central:  87.7 79.5 72.8 66.0 58.4
AL Central        W    L    Pct3  Avg W  Avg L  Champions  Wild Card   Playoffs      1D Change 7D Change
Indians           22   23   .518   84.9   77.1   62.80773    1.15349   63.96121       -4.53598   4.52210
Tigers            20   26   .457   73.6   88.4    9.88995     .59205   10.48200       -0.84035  -2.59865
Twins             19   23   .475   78.4   83.6   24.88842    1.36633   26.25475        4.68116  -5.87456
Royals            14   32   .412   62.4   99.6     .66981     .01497     .68478       -0.33442  -0.67495
White Sox         13   30   .432   65.1   96.9    1.74410     .04158    1.78568         .33901    .05393

Average wins by position in AL west:  102.2 91.8 85.7 79.2 65.4
AL West           W    L    Pct3  Avg W  Avg L  Champions  Wild Card   Playoffs      1D Change 7D Change
Astros            30   18   .621  101.0   61.0   79.90038   13.89225   93.79263        1.17269   2.21452
Mariners          27   19   .503   84.0   78.0    4.56511   20.18228   24.74739       -2.45705    .90059
Angels            26   21   .535   87.5   74.5    9.07788   32.60801   41.68589        2.33996 -18.16841
Athletics         25   22   .526   85.9   76.1    6.44493   26.60086   33.04579        3.42102  17.24401
Rangers           18   30   .428   66.0   96.0     .01172     .20886     .22057       -0.17610  -0.66395

Average wins by AL Wild Card:  97.2 91.3

Average wins by position in NL East:  97.4 90.5 84.6 77.1 64.0
NL East           W    L    Pct3  Avg W  Avg L  Champions  Wild Card   Playoffs      1D Change 7D Change
Braves            28   17   .558   93.4   68.6   49.44248   26.50692   75.94939       -2.02402   1.35403
Phillies          26   18   .529   88.4   73.6   22.98183   28.89880   51.88062       -5.68060  -4.54583
Nationals         24   21   .551   88.0   73.0   23.69850   28.90560   52.60410       -7.26890 -24.26026
Mets              23   19   .478   79.0   83.0    3.82811    9.13366   12.96177        2.67908   4.09863
Marlins           17   29   .424   64.9   97.1     .04909     .16504     .21413         .08423    .08554

Average wins by position in NL Central:  96.6 90.1 84.9 78.9 65.1
NL Central        W    L    Pct3  Avg W  Avg L  Champions  Wild Card   Playoffs      1D Change 7D Change
Brewers           28   19   .513   87.2   74.8   20.96412   24.74993   45.71405       -2.08915  18.10660
Pirates           26   20   .516   85.4   76.6   16.16587   20.33888   36.50474       -0.40088  -8.23361
Cardinals         25   19   .512   85.5   76.5   16.33475   20.83822   37.17297        7.61271   6.17795
Cubs              25   19   .562   92.0   70.0   46.47342   23.44089   69.91431        7.01630  17.69149
Reds              16   32   .439   65.6   96.4     .06185     .18093     .24278       -0.13405  -1.53637

Average wins by position in NL West:  90.5 83.9 79.1 74.2 67.3
NL West           W    L    Pct3  Avg W  Avg L  Champions  Wild Card   Playoffs      1D Change 7D Change
Diamondbacks      25   21   .525   86.4   75.6   50.00650    5.09508   55.10157       -4.82309 -21.46931
Rockies           25   22   .477   79.9   82.1   18.24718    3.77039   22.01757       -2.93236  -0.43098
Giants            24   24   .496   80.7   81.3   19.67898    4.54485   24.22382        3.34536   4.32536
Dodgers           20   26   .495   77.2   84.8    9.80128    2.94109   12.74237        4.17525   7.08207
Padres            20   28   .449   70.8   91.2    2.26607     .48975    2.75582         .44012   1.55471

Average wins by NL Wild Card:  93.1 89.5

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) for each team starts with their W3 and L3 from the Adjusted Standings. A regression is applied to derive the EWP for the rest of the season, which is going to be between the current winning percentage and .500. To allow for uncertainty in the EWP, a normal distribution centered on the EWP is randomly sampled, and that value is used for the remainder of the season in that iteration. 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.