Question about : backing the (football-)outsider on Betfair

[Tonyvdb]

hi, a question for the experts here : :) On Betfair this happens a lot : * home or away teams, being the outsider, getting massive odds towards the nearing of KO. For example : ->a team gets 3,50-4,00 at the normal bookies, but gets 4,75 to even 5 or 5,50 on Betfair. ->a team gets 2,50-2,60 at the normal bookies, but gets over 3,00 on Betfair. My question is : although it is theoretically certainly a valuebet (you certainly overwin the bookie's bias), is it one in real life too? In other words : if I 'blind-bet' all these massive outsider-odds, would I be in profit in the long term?

[aliando]

Re: Question about : backing the (football-)outsider on Betfair i'd imagine that 'blind-betting' would result in a loss, but if you can spot potential picks that have this extra edge, then you could increase/make a profit. perhaps worth some sort of paper trial mate?

[algorithmbetting]

Re: Question about : backing the (football-)outsider on Betfair hi, id say there is not necessarily value as you seem to be assuming. bookies do not have the same margin profit on all prices eg their prices are always 12% worse than the estimated fair odds. you cannot therefore assume any betfair prices in excess of 12% over the bookies offer value. ive found that outsiders, as you refer to, are generally poor value even on betfair/wbx as the fair odds are even higher per my calcs therefore some will and some wont be value. you need to calculate your own fair odds or develop some method as aliando says

[Tonyvdb]

Re: Question about : backing the (football-)outsider on Betfair I'm well aware of the fact that the overround for bookies is more than 10-12% on outsiders : I will provide some valuable information I worked on for weeks, to prove this : I backtested the average odds for away-outsiders for 5 seasons (almost 20.000 games in total in 10-12 European leagues : England, France, Germany, Spain, Italy, Belgium, Greece, Netherlands,Turkey), using Joe Buchdahl's spreadsheets, and came to this conclusion : * average bookie odds : 2,50-2,99 : 3949 games : blind betting on average odds would have resulted -13% * average bookie odds : 3,00-3,99 : 5840 games : blind betting on average odds would have resulted -15,8% * average bookie odds : 4,00-4,99 : 3110 games : blind betting on average odds would have resulted -19,7% The question is : IF you could beat THIS overround, would you have a profit in the longterm? On Betfair, every week dozens of the opportunities (not only in the above named leagues) rise to beat these percentages, sometimes by an extra 10-15%, especially when KO is nearing and some people want to have a quick lay on the outsider...

[Djordje]

Re: Question about : backing the (football-)outsider on Betfair great research Tony :ok blind betting will never give you a profit, doesnt matter are you betting blindly on underdogs or on favorites

[Tonyvdb]

Re: Question about : backing the (football-)outsider on Betfair But IF you should bid blind on ALL odds giving at least 10% MORE then the overround I backtested, you should have a long term profit of 10% in theory ... rounded down by some oddities to 6-7% For example : 4,50 average bookie odds : + 19,8% overround = 5,39 + 10% profit = 5,93 (= 6,20 on Betfair (5%)) So the question is : if, in theory, I should bet every time I get odds of 6,20 or more on Betfair, when the average bookie odd is 4,50, should I be in profit in the long term? In theory I should, shouldn't I ? Or do I miss something here?

[vabanque]

Re: Question about : backing the (football-)outsider on Betfair yes, unfortunately you miss something here: your theory demands one of two things: or you get a 10%-plus on overround on ALL these underdogs, or the overround on all these underdogs (according to their odds) is constant (the same). but as you do not get these 10%-plus on everyone (sometimes yes, sometimes not) and the overround can swing in real life (who knows?) the times you do get the good odds, the "true" overround could be even higher, while the times you don't get it the overround could be lower. that's why blind systems don't work.

[Tonyvdb]

Re: Question about : backing the (football-)outsider on Betfair True, Vabanque, but that's why I would take 10% on the top of the overround I calculated : I estimate half of this profit gets lost on miscellaneous factors, as the one you named. Following this thought, I should have a 5% profit in the long term... but it could be more, that's true ... or less?? but maybe I should 'papertrail' this first before I play with real money.

[AndyR]

Re: Question about : backing the (football-)outsider on Betfair Tonyvdb, one of these miscellaneous factors is that there is a percentage overround in addition to the commission on Betfair - you can see it on the left-hand side as a percentage over 100%, and this overround is invariably all on the outsider and not on the favourite, especially at long odds. This can be small (1-2%), but you need to add this to any calculations. I have to say, though, that the betfair odds are as close as you are likely to get to the true odds for many games, so you will need to get higher odds than the average betfair odds to make any profit. You can only put them up and hope they get matched, not sure how you can paper trail this but maybe somebody else can help. Good luck