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 18 08:05:19 EDT 2018


Average wins by position in AL East:  109.5 98.1 89.2 73.9 47.3
AL East           W    L    Pct3  Avg W  Avg L  Champions  Wild Card   Playoffs
Red Sox          103   47   .581  109.5   52.5   99.99890     .00110  100.00000
Yankees           91   58   .567   98.1   63.9     .00110   99.90397   99.90507
Rays              83   66   .488   89.2   72.8     .00000     .46843     .46843
Blue Jays         68   82   .485   73.9   88.1     .00000     .00000     .00000
Orioles           43  107   .415   47.3  114.7     .00000     .00000     .00000

Average wins by position in AL Central:  91.1 75.9 66.7 63.7 57.0
AL Central        W    L    Pct3  Avg W  Avg L  Champions  Wild Card   Playoffs
Indians           83   66   .593   91.1   70.9  100.00000     .00000  100.00000
Twins             69   81   .522   75.9   86.1     .00000     .00000     .00000
Tigers            61   89   .444   66.5   95.5     .00000     .00000     .00000
White Sox         59   90   .431   63.8   98.2     .00000     .00000     .00000
Royals            52   98   .430   57.0  105.0     .00000     .00000     .00000

Average wins by position in AL west:  101.2 95.8 89.1 79.9 69.8
AL West           W    L    Pct3  Avg W  Avg L  Champions  Wild Card   Playoffs
Astros            94   56   .577  101.2   60.8   98.33795    1.66205  100.00000
Athletics         90   60   .502   95.9   66.1    1.66205   97.39057   99.05262
Mariners          83   67   .514   89.1   72.9     .00000     .57388     .57388
Angels            74   76   .510   79.9   82.1     .00000     .00000     .00000
Rangers           64   86   .502   69.8   92.2     .00000     .00000     .00000

Average wins by AL First Wild Card:  98.3
Average wins by AL Second Wild Card:  95.6

Average wins by position in NL East:  89.3 83.3 81.4 75.8 63.5
NL East           W    L    Pct3  Avg W  Avg L  Champions  Wild Card   Playoffs
Braves            83   67   .517   89.3   72.7   98.71982     .03170   98.75152
Phillies          76   73   .492   82.2   79.8    1.13377     .12400    1.25776
Nationals         76   75   .548   82.6   79.4     .14642     .12054     .26696
Mets              70   80   .479   75.8   86.2     .00000     .00000     .00000
Marlins           59   91   .404   63.5   97.5     .00000     .00000     .00000

Average wins by position in NL Central:  94.9 91.9 88.3 80.8 69.5
NL Central        W    L    Pct3  Avg W  Avg L  Champions  Wild Card   Playoffs
Cubs              88   62   .539   94.8   67.2   88.19200   11.78859   99.98059
Brewers           86   65   .512   91.9   70.1   11.20070   87.39111   98.59180
Cardinals         83   68   .507   88.4   73.6     .60730   64.46032   65.06761
Pirates           75   74   .484   80.8   80.2     .00000     .01040     .01040
Reds              64   87   .451   69.5   92.5     .00000     .00000     .00000

Average wins by position in NL West:  89.9 87.6 83.4 76.7 64.4
NL West           W    L    Pct3  Avg W  Avg L  Champions  Wild Card   Playoffs
Dodgers           83   68   .573   89.5   72.5   72.06972   12.14504   84.21476
Rockies           82   68   .508   88.0   74.0   27.51062   23.28967   50.80029
Diamondbacks      78   73   .488   83.5   78.5     .41967     .63864    1.05831
Giants            71   80   .501   76.7   85.3     .00000     .00000     .00000
Padres            60   91   .420   64.4   97.6     .00000     .00000     .00000

Average wins by NL First Wild Card:  91.9
Average wins by NL Second Wild Card:  88.8

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.