Thursday, 9 September 2010

Selective Laying

I spent some more time looking at the data from last season, and need to clear up a couple of points raised by Joep. One is that the prices used are from Bet365, and the second is that I do not use Betfair if I am subject to the Premium Charge, but while that was an issue for last season, it isn't right now, with my total charges running at 20.62%. So the prices and the assumed 5% commission can probably usually be bettered, but I prefer to err on the side of caution.

SimonM said...

Fascinating -- any conclusions on the reasons? Are the markets more efficient in Italy and Spain? Less attention paid to Germany? Or is it the nature of the football -- Bundesliga being a more open championship than Serie A or La Liga? Whatever the reason, thanks for the blog. Real food for thought with each post.
Certainly, the Bundesliga is arguably more competitive than Spain with Bayern Munich averaging 2.06 points per game last season compared with Barcelona's 2.61, but Internazionale's 2.16 points a game puts Serie A closer to the Bundesliga than to La Liga by this measure. France and Germany are almost identical too, but there are definite differences between these two leagues when looking at the performance of favourites. It's also true that worldwide, there is less interest in German games than Italian or Spanish, but it is still a major league - we're not talking Ryman League here, so it's hard to believe that the prices should be any less accurate than those of the other top leagues. Last season every team won at least two away games, something not seen in the other leagues, and there were some frankly bizarre scorelines which we have already seen again this season (Bayer Leverkusen 3-6 Borussia Moenchengladbach).

Anonymous asked "
What would the total P/L be across all those Leagues?",
and the rest of this post should answer that question. I mentioned that I included the Scottish Premier in my data yesterday, but it really doesn't belong in such exalted company, so I am excluding it from here on.

Backing the favourite in every match in the top five European Leagues would have resulted in a -2.61% ROI. As mentioned yesterday, this strategy would have been profitable in Italy and Spain. Laying the favourite in every game would have resulted in a loss of 1.85%.

I looked at the results of laying favourites at various price ranges.

Laying every odds on favourite would have been profitable only in Germany (25.38%) and France (2.23%). Across all leagues, the total loss would have been just 0.32%.

Laying just those favourites priced at 1.5 or less, and the loss across all leagues would have been 7.19%. Again this would be profitable in Germany (15.68%).

Narrowing the bands down still further, and laying any favourite priced at 1.19 or less would not have been a good strategy - just one winner (in France) from 49 bets for a loss of 86.55%, but if we take these out of the equation, things get interesting.

In Italy, favourites priced between 1.4 and 1.89 are overall value to back, whereas in Spain, favourites need to be priced at 1.7 and above to be value. Laying at prices between 1.3 to 1.69 is profitable, but not hugely. Overall, laying the favourite in Spain doesn't appear to be a profitable strategy.

In the Premier League, laying favourites priced at 1.9 or more is profitable (4.21%).

Overall France is pretty much a wash. Laying all favourites would have resulted in a 1.17% ROI, although favourites in the 1.5 to 1.69 are profitable to lay (33.49%).

That's a lot of numbers to take in, but to summarise, a strategy of laying all odds-on favourites across all leagues would be unwise, but with a few tweaks, it has some potential.

These numbers are from last season only, so too small a sample to draw any firm conclusions from, but just to throw it out there, if we exclude Italy and Spain from our selections, as well as any favourites priced below 1.3, we would have a total of 478 lays, and a profit of 63.47 units (13.28%). Not too shabby.

When time permits, I'll go back to earlier seasons and see if these findings hold true longer term. As I said yesterday, it looks like a low-risk strategy that could easily be quite profitable.


Matt said...

Mate have a look at Jonathan Lowe's site called I used to use it ages ago. he is a stats freak from Melbourne Uni. He has a lot of free info you might fine relative to what you do.
Remember STATS is the single best tool any punter should be using.
Cheers, Matt

Anonymous said...

You are simply guilty of data mining to suit your own needs.

i.e. changing criteria over and over until you find some parameters which show a profit.

Blind strategies like those suggested will not be profitable long-term. Market efficiency will put paid to that, as indicated by the overall results.

A question for you.

When laying the favourites for the purpose od your research, did you lay one unit each time? Or did you lay "to lose one unit"

Anonymous said...

ignore the last question. have spotted you risked a unit loss on each lay

Skinnyfat said...

"Blind strategies like those suggested will not be profitable long-term. Market efficiency will put paid to that, as indicated by the overall results"

Spot On. I am sure prior years will show this