Determining expected odds

[johnnic]

This is probably a little out of left field and not at all relevant to BA but I thought I would ask anyway.

If there are, say, two rounds of a tennis tournament to go (four players) and I observe the following prices for the Winner market:

Player A - $1.27
Player B - $8.40
Player C - $22.00
Player D - $19.00

Is there any way that I can determine the range of expected prices that will apply after the next set of matches and there are only two players left? In this instance in the semi-final Player A is playing C and B is playing D.

I would like to know what the range of expected prices will be for the two winning players. For example, if the two favourites win (A and B), is there any relationship between their current prices $1.27 and $8.40 and their expected prices for the final?

I understand that it will depend on other variables such as how well they play in their semi final matches, injuries, etc but I'm still wondering if, these variables aside, there is an expectation model that can be identified.

John

[milfor]

It is possible to calculate that but only with the additional information of the
odds between A and C and between B and D.

[johnnic]

Player A - $1.10
Player C - $10.5

Player B - $1.46
Player D - $3.15

[milfor]

This leads to a system of 4 equations (1 for each player) and 4 variables.
So it's definitely solvable but too tedious to solve it 'just for fun'.

[johnnic]

I wasn't actually asking the question "just for fun". Are you able to offer anything more constructive?

[Ian]

You can work out the effective price you would be getting for the final as follows.

Assume you back the favourite ("A") for £100 @ 1.27 and you place a "saver" bet to recover your stake should A lose ie 100/(10.5-1) = 10.53.

If A wins and reaches the final, the effective odds you've got for the final is
((27-10.53)/(100+10.53)) + 1 = 1.149

[jokerjoe]

See here, hope you can follow it's a bit rough.

http://www.mediafire.com/?2ayzfvytqjn

I used solver to find the values. To calculate in realtime you'd want to expand out the last four equations and convert to a matrix equation. Google simultaneous equations and matrices for help on that.

[johnnic]

Thanks,very useful.