Stats on betfair prices

[johnoleary]

hi,
think i may have found an edge here but need some help,is there anywhere online i would be able to find the odds on a draw and away win if the home team is a certain price on betfair..for example if the home team is 1.7 or 1.2 or say 1.55 what then would the other prices be for draw and away,what im really looking for is a full run down of all the home team prices and the possible results for the draw and away..can anyone help..many thanks.

[WhyAlwaysMe]

Interesting question but I don't have the answer unfortunately. The draw and away figures will be influenced by the goal expectation for the match in question. Also different leagues will have different characteristics.

Hopefully Doubleback or Edi8 can produce something more useful. If not you could always ask The ****** .

[johnoleary]

thanks for the reply..obviously there will be some slight variations but if there was a lot of data then hopefully i could get an approximate price or prices.

[Cran]

http://data.betfair.com

[johnoleary]

thanks cran but dont have enough betfair points to access the data!!

[Cran]

You can also download it from here

Betfair Data

you want the not_horses files.

But is only up to November 2011 at the moment (until I get round to updating it again)

[johnoleary]

thank you cran am just downloading it now its gona take a while lol...im hoping to find something like a spreadsheet online which will give me a rough guide for all the prices.

[doubleback]

Thanks for that great handover, WAMO ...

John, John, John ...

If we start with your comment, "if there was a lot of data then hopefully i could get an approximate price or prices."

The above will simply not work, mate. If the odds for a home side were 1.7, the draw could be x, and the away could be y.
There's not a prescribed set of draw and away odds that could be applied to a home side that is trading at 1.7.
Matches are priced up/find a price in a more complex way than this.

You are now entering the murky world of football modelling ...

For starters, have a look at the following link ...

Bivariate Poisson Calculator

You will see 3 variables, with the option to show the results as Odds or Probability (select Odds):

• Home Goal Expectation
• Away Goal Expectation
• Covariance

Have a play and try to make the home side to be odds of 1.7, or indeed, whatever odds you would like to explore if the home side was on odds specified by yourself. Then, change the Away Goal Expectation and Covariance, then bring the home side odds back to 1.7, or whatever you specified, using the sliders. You will see that the home side odds do not dictate the draw and away odds and that there is much variance according to goal expectancy.

Once you have done that, come back, and we can develop you into the next Psychoff ...

[johnoleary]

hi doubleback,thanks for your reply,i am fully away there is no exact pricing going on here,i am merely looking for a rough guide on the prices of a draw and away win for particular home prices,having had a close look at betfair prices over the last few days it is clear there are some similarities enough for me to have been able to find a slight edge,i was just hoping that somewhere out here there may be a spreadsheet that could save me a lot of time..thanks

[doubleback]

Originally Posted by johnoleary

i am fully away there is no exact pricing going on here,i am merely looking for a rough guide on the prices of a draw and away win for particular home prices ...

You wont find a rough guide ...

If we use 1.7, as an example again, I know your looking for different home side odds, but as an example, I will stick with this ...

If we turn it into a probability percentage, i.e.,

the home, away, and draw percentages must equate to 100%, not taking the overound into consideration.

Therefore, odds of 1.7, can be expressed as;

1/1.7 = 0.588 implied probability

0.588 x 100 = 58.8% chance of winning

If the home, away, and draw percentages must equate to 100%

100% - 58.8% = 42.2%

42.2% left on the table, to be divided up between the away and draw odds.

There is no way to divide up, definitively, a 42.2% probability between the away and draw, based soley upon the home side probability.

Now, is the question that you are asking correct? Have a think, mull it over ...

[WhyAlwaysMe]

I think a spreadsheet would just give you garbage tbh. Historical data from one league over a decent time period could be a good option.

Part of the problem is that at very short odds like 1.20 the draw and away can get awfully price sensitve.

[johnoleary]

im afraid your wrong doubleback i suggest you go back to betfair and study the odds as you can quite clearly get a rough guide price for draw and away when you look at the home prices...come back to me when youve done it

[doubleback]

That's quite a naive response, John. Perhaps you should stay in the smaller pond whilst accumulating enough points to acquire Betfair's historical data?

[custard]

I never have regard to historical data but, the funny thing is, history tends to repeat itself

If you want figures on relative prices of home win, draw and away win, you need look no further than The Toy. Just open a few soccer coupons and you will have a huge number of prices available for your brains to mess around with. More important, these will be real prices which are actually available today.

"History is more or less bunk. It's tradition. We don't want tradition. We want to live in the present, and the only history that is worth a tinker's damn is the history that we make today." (Chicago Tribune, 1916).

Henry Ford

[lcredd]

Originally Posted by johnoleary

you can quite clearly get a rough guide price for draw and away when you look at the home prices

If you can clearly get a rough guide, why are you asking for one?

Originally Posted by johnoleary

i am merely looking for a rough guide on the prices of a draw and away win for particular home prices

[custard]

When you've seen hundreds of markets, something rubs off and so it's possible to have an idea of the third price if one knows the other two.

There is great variation, however, and this can be proved easily by doing simple multiplication of the three odds. If there was a direct correlation between the home win, away win and draw odds, the figure arrived at by mutiplying the three together would be pretty well constant. In reality this doesn't happen. Just picked two games at random, and had multiplied odds of 21 and 29. This indicates that there is not a direct relationship between odds in football markets. Doubleback is correct.

[custard]

Sorry to follow up my own post but there are lot of people out there who can do all sorts of tricks with Excel and they may be able to help here.

We are led to believe that markets are efficient and that bots operate to ensure this. It should not be beyond the realms of possibility for one of the clever guys to come up with a spreadsheet which showed all the possible combinations of odds ( obviously within sensible ranges ) for home, draw and away win. Each set of three odds would come up with a balanced book (100% ) for that specific market.

I am sure it is possible to do this. The question is - would it be of use to any of the guys who are presently looking at past statistics ?

Certainly, they would never be of use to me but those who want them might find this approach helpful.

My post above is somewhat simplistic but it aims to illustrate the vast number of combinations of odds which are possible and to show that it is really very complex. A rough guide would seem to be inadequate when one considers that most traders work within small margins.

[Cran]

Try (1/HomeOdds + 1/AwayOdds + 1/DrawOdds) x 100

[custard]

I was hoping you would do it. I'm just about able to switch Excel on.

[doubleback]

Carrying on from Cran's post and working backwards for a bit, if we were to separate out the Home, Draw and Away probabilities, and didn't convert it to a percentage, we'd end up with the implied probabilities for each of the Match Odds, e.g.,

(1/HomeOdds + 1/AwayOdds + 1/DrawOdds) x 100

Home: 1.48 = 1/1.48 = 0.6756

Draw: 6.38 = 1/6.38 = 0.1567

Away: 9.41 1/9.41 = 0.1062


The implied probabilities are derived from the correct score market, so if we wanted to know the odds of the Home side, we need to calculate the probability of each score line, then add up all the implied probabilities of the score lines where the Home side win, e.g.,

All the score lines highlighted are added to give the Home side implied odds.



The same goes for the Draw and Away implied probabilities ...





Once we have the implied probabilities for Home, Draw and Away, it is then just a case of dividing by 1 to give us the odds ...

Home: 1/0.6756 = 1.48

Draw: 1/0.1567 = 6.38

Away: 1/0.1062 = 9.41

All the other secondary markets are worked out using similar methods. The Over 2.5 market, for instance, is made up from all the score lines that have 3 goals or more ...

The real skill is working out the correct score lines ... The sheet that I use, broadly speaking, calculates Lambda1, Lambda2, which are the goal expectancies for the Home and Away sides respectively and are calculated using many team specific factors, and Lambda3, which is the covariance between Lambda1 and Lambda2.
The above is just an outline, there is much more to it than that but I don't want to bore anyone to death, or give away my hard work! I hope it demonstrates how varied the odds of a game can be and how they are influenced ...

As an aside, I have been periodically copy and pasting the In-Play Football coupons throughout the day. I then used the sort & filter function in Excel to numerically list the matches according to the Home side odds. I done this to show how different matches with their respective Home sides having the same, or similar odds, have different draw and away odds ... (see attachment - different times of capture are on sheets 1,2,3)