Last update: Thu Jul 2 07:31:03 2009 PT
Playing the rest of the season a million timeswith some help from PECOTA
by Clay Davenport
See the original version of this report, based entirely on real data (no projections). And the ELO version of this report, based on an ELO rating scheme.
Generated Thu Jul 2 07:17:39 EDT 2009
Average wins by position in AL East: 100.3 94.1 87.8 79.9 71.4 AL East W L Pct3 Avg W Avg L Champions Wild Card Playoffs Red Sox 48 30 .579 98.0 64.0 59.95202 30.01598 89.96799 Yankees 45 32 .582 95.0 67.0 33.77908 43.85153 77.63062 Rays 44 36 .534 88.3 73.7 5.85308 18.92091 24.77399 Blue Jays 42 38 .481 79.8 82.2 .40718 2.25837 2.66555 Orioles 35 43 .454 72.3 89.7 .00863 .09601 .10464Average wins by position in AL Central: 88.7 83.3 78.5 72.2 66.4 AL Central W L Pct3 Avg W Avg L Champions Wild Card Playoffs Tigers 43 35 .485 86.0 76.0 53.60084 .60381 54.20464 Twins 41 39 .472 82.3 79.7 25.53681 .51386 26.05067 White Sox 40 38 .481 81.2 80.8 19.64100 .55076 20.19177 Royals 33 44 .436 70.5 91.5 .81188 .00937 .82125 Indians 31 49 .444 69.2 92.8 .40947 .00175 .41122Average wins by position in AL west: 89.7 84.1 78.9 70.0 AL West W L Pct3 Avg W Avg L Champions Wild Card Playoffs Angels 42 34 .499 87.1 74.9 55.16251 1.14044 56.30294 Rangers 42 35 .470 82.6 79.4 23.12941 .91037 24.03978 Mariners 39 38 .492 82.5 79.5 21.04469 1.11576 22.16045 Athletics 33 44 .438 70.7 91.3 .66339 .01110 .67449 Average wins by AL Wild Card: 94.2Average wins by position in NL East: 90.0 85.1 81.1 76.3 55.1 NL East W L Pct3 Avg W Avg L Champions Wild Card Playoffs Marlins 41 39 .479 81.2 80.8 13.93099 2.62399 16.55498 Phillies 39 36 .526 86.4 75.6 45.08389 4.64937 49.73326 Mets 38 39 .488 80.6 81.4 12.30244 2.49037 14.79281 Braves 37 40 .540 84.2 77.8 28.68268 4.76045 33.44312 Nationals 22 54 .380 55.1 106.9 .00000 .00000 .00000Average wins by position in NL Central: 91.1 86.6 83.3 80.1 76.3 70.4 NL Central W L Pct3 Avg W Avg L Champions Wild Card Playoffs Brewers 42 36 .522 87.2 74.8 41.50625 7.34143 48.84768 Cardinals 42 38 .512 84.8 77.2 23.80241 6.67448 30.47690 Reds 38 38 .494 81.7 80.3 10.86209 4.41817 15.28025 Cubs 37 38 .519 83.8 78.2 19.35475 6.14076 25.49550 Astros 37 39 .476 78.3 83.7 4.11008 1.76338 5.87346 Pirates 36 42 .423 72.0 90.0 .36442 .15123 .51565Average wins by position in NL West: 99.5 89.0 81.5 72.8 66.4 NL West W L Pct3 Avg W Avg L Champions Wild Card Playoffs Dodgers 50 29 .575 99.2 62.8 89.67892 7.70766 97.38658 Giants 42 35 .524 88.0 74.0 8.87037 39.42846 48.29883 Rockies 41 37 .467 82.3 79.7 1.43317 11.63349 13.06666 Padres 34 43 .423 70.7 91.3 .01246 .16344 .17589 Diamondbacks 31 47 .444 69.0 93.0 .00509 .05333 .05842 Average wins by NL Wild Card: 90.5
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.
At least, that's how it works in the regular version. For this, PECOTA adjusted version, the regression isn't done to the mean (.500), but rather to the PECOTA projection made at the beginning of the year (numbers which can be found here). The Yankees were projected to be a .580 team - and so the EWP described above will nudge their record towards .580, not .500. 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.