Post Season Predictions Using The Bill James Formula
By Fred Owens
Oct 7, 2015; Pittsburgh, PA, USA; General view as the grounds crew prepares the field for the National League Wild Card playoff baseball game between the New York Yankees and the Houston Astros at PNC Park. Mandatory Credit: Charles LeClaire-USA TODAY Sports
The post season is underway and everyone is making their predictions. I was digging around the net the other day and found out that back in the dark ages of statistical analysis Bill James created a formula to predict post season success.
According to a post on seamheads James first put this together when I was a youthful 23 year old.
". . .(James) wrote about the system for Inside Sports magazine in 1982, then expounded on it in his 1984 Baseball Abstract. He developed the system in 1972 and it accurately predicted the World Series winner at a 68% clip for 12 years. Then he went back and used it to predict all of the postseason series of the 20th century and it returned a success rate of 73%."
There are some things you’d expect in the system and some things that will make you scratch your head. Here are the critical areas and the relative points.
| W/L | 1/2 point for each game of difference between the teams W/L record |
| Runs | 3 points for most runs scored |
| 2B | 14 for the LEAST doubles |
| 3b | 12 point sfor the most triples |
| HR | 10 points for the most homers |
| BA | 8 points for the LOWEST batting average |
| E | 8 points for the least errors |
| DP | 7 for turning the most double plays |
| BB | 7 points for ISSUING the most walks |
| SO | 19 for the most shutouts |
| ERA | 15 points for the team the ERA farthest below league average |
| Post | 12 points for most recent post season performance – if both went the team that progressed the farthest |
| H2H | 12 – NLDS and NLCS series only 12 points for the team who won the head to head series |
According to the seamheads post, the team with the least doubles gets points for not being as aggressive on the bases and I suppose not getting thrown out in the course of being aggressive.
That post also quoted James explaining why the higher batting average didn’t get the points.
"“Why do teams with high batting averages do poorly in World Series play?” asked James. “A simple reason: it takes them too many hits to score.”"
Okay, got it! So why does the team who walks more get points? James has never said but feel free to ask him at Bill James online.
So let’s predict!