maths betting question for those clever than me..

problem is with maximum no of consecutive bets he is likely to land(theory) & reality
The results of his previous bets have no bearing on his next bet.

His average price is 2.50 and each bet has a negative expectation to the customer of 2%.

What exactly does this mean please?

It means he is placing bets at 2.5, when the fair price (reflecting the true probability) averages around 2.55.

Ignoring commission.

The simple answer to the question would be 'use Kelly', and forget about the max number of winners he is likely to get. Although I could tell you how to work that out if you really want to know.

I make it more like 2.53. That is 1.5/1.53= .9803.
Nitpicking I know. Just can't help myself.

FAFH, from this and your other posts, I don't think you understand as much as you think you do! The investor is right - it's close to 2.55.

yes it's 2.5/0.98

backing at implied probability of 0.4, when the real probability is 0.392, leads to an expected loss of £20 for each £1000 staked, which equates to a negative expectancy of 2%

I'm defining an edge as the edge on the odds not on the probability.
eg If I have an edge of 2% on an evens bet I would say that I have odds of 1.98, you say it would be 1.96 based on 2% of the probability.
But now at least I understand the term " value  " prices, as you are referring to them.
You are really referring to prices reflecting "value " probability.
Makes more sense I admit.

Imlac
I have never professed to understanding everything or, in fact, even much at all.
I simply question things when I don't understand them clearly.
If I get clear, concise answers pointing out my misunderstandings then, as in this case, I accept them, take them on board and move on.
Unfortunately the answers I get are never usually that concise.
There's a lot of  ery wooly thinking that goes on here( me included) and many ridiculous claims of success.
I just happen not to believe unconditionally everything I read, not only here but everywhere in general.

But you have to admit that in general people refer to getting x% better prices on BF than say somewhere else.
I have always taken that to mean exactly what it says.
I didn't interpret as being prices that represent x% better probibility. My mistake.
I admit the latter it is a far more accurate and correct approach, particularly in relation to the " value" betting strategies.

But methinks I protesteth too much.
Certainly a fault I have.

Stop waffling and go and stand in the corner.

I know.
I think our posts might just have crossed.

[;)]

Just tell me when I can come out again and play.

I promise to be a good little boy.

The most important factor of all is the size of the sample that gave you results of average price 2.5 and expectation -2%. The sample would have to be in excess of at least 1000 for you to have any degree of confidence that the intitial data is correct.

You can make this calculation but it is unsuitable for the purpose you intend