So some baseball standings will now include probability of reaching the playoffs:
As of today, the National League East-leading Philadelphia Phillies are 61-50, 7-3 in their last 10 games — and have a 65% chance of making the playoffs. The first two figures are familiar to any baseball fan. The last one — forward-looking, uncertain, unverifiable and instant grist for debate — is a relatively new beast.
For the past month, ESPN.com’s Major League Baseball standings have included postseason probabilities, broken down by chance of winning the division and winning a wild card. It’s a brave step forward for standings, longtime fixtures of newspaper agate and more-recent staples of online sports sites. And ESPN isn’t yet sure playoff probabilities, as supplied by an online standings provider called Coolstandings, are here for the long term.
The playoff probabilities make use of teams’ so-called Pythagorean records, which I wrote about last year. These records, which project how well a team should have done based on the number of runs it scored and allowed, have been shown to better predict performance in the future. After each day of games, Coolstandings runs a computer simulation of the rest of the season one million times, using Pythagorean records and other factors including home-field advantage, strength of opponents and performance the prior season to calculate the probability of winning each remaining game. Coolstandings assigns more weight to recent games and regresses teams to the mean, based on historical data, to account for extreme results that arise by chance. For each of these virtual seasons, a playoff slate is assigned; a team’s postseason probability is the percentage of these virtual seasons in which the team is still playing in October.
Cool math, but I’m not sure I approve.