Idle Pursuits

I decided to talk about my latest hobby - horse race analytics. Its something I started thinking about twenty years ago and, after several false starts, I believe I have finally worked out the maths of what I wanted to do and coded up an approach that works. I'm not sure why it took so long!

The basics. Horse racing is an uncertain business. Generally speaking it is never possible to accurately predict the results of a horse race, unless you are a) veeeery lucky or b) own all the horses. The best prediction is usually that the favorite will win. But typically the odds the bookmakers will give you on that happening will not be very good, so if you do it every time, you will, in the long run, loose money. If you back the horse where the bookies are giving the best odds, i.e. they pay you the most for a win, you will also loose money overall, because these horses will win less often. Not never, just less often.

There is, surprisingly, one reliable strategy for making money form horse racing, and that is to pick "value winners" which means that you pick horses where the bookmakers are offering "good value". In other words, they are offering better odds than the quality of the horse would suggest. In yet more other words the horse is more likely to win than they think it is. The "true odds" of the horse are "shorter" than the bookies odds. So, all we have to do is work out the true odds and back horses where the bookies are offering longer odds.

Therein, of course, lies the problem. How to calculate the "true odds". How to calculate odds better than the bookies, whose job it is to do this. They have teams devoted to it; observing races, going to stables, timing, observing, etc. This is what I'm trying to do. It won't be easy - but I think I at least have some maths that can help. I'm planning to use the kind of stuff economists and stock traders know about (at least some of them). To drop in a name, Bayes is the key to this. Bayes is the key to a lot of things.

What I plan to do is develop and refine the method over the coming weeks, publishing what I calculate as the true odds, comparing these to the bookmakers odds and highlighting my betting  recommendation. Over the weeks, we'll see if its working and hopefully refine as we go!