2011-2012 predictions

2011-2012 predictions start when teams have played two home games and two away games each. So a few weeks away yet.

Scibet

I hadn't previously noticed that http://www.scibet.com has an archive of their predictions for previous seasons. At least I think that's what the "Results" pages are. They're not labelled very well. Anyway, I investigated a bit, and found that my own method makes more money, except in the last quarter of the season, where Scibet's average and variance are both higher. Maybe English leagues are a weakness for them.

Kelly shortcomings

The Kelly bet isn't perfectly suited to football betting. It gives the optimum stake size when making repeated bets at the same odds and probability, but this is not the situation in football betting. And it can't help when placing bets on several markets at the same time either.

Kelly bug

There was a bug in my Kelly calculations! Effectively I was using the estimated probability as the stake size instead of the proper Kelly calculation. Hopefully when I retest with the correct calculation the results should be better.

Unfortunately I think this is a symptom of being forced to work on my system in very short bursts and thus lacking time to refactor and fix bugs. I wonder how many bugs remain...

Divide and conquer

I've been experimenting with splitting up the season into sections and treating them separately, with some success. The first half of each season seems pretty intractable though.