Bradw

On the figures supplied I think you'd have a negative expectation of about 6.5%. We should really be using the sum of the chances of all selections, not their average SP, but this is close enough.

Observed successful lay selections =

Total Lays * (1-Win SR) = 2000*(1-.17) = 1660

Expected successful lay selections =

Total Lays * 1-(1/Average SP all selections) = 2000*1-(1/8.97) = 1777

Advantage = (1660/1777)-1 = -0.0658

What this is telling us is that you should have had 117 more successful lay bets than the 1660 observed based on the average SP of all your selections. So in the long term you could expect to lose $0.0658 for every lay doller risked. You need to find a way of getting your lay strike rate up without increasing the average SP of all selections, or try to reduce the average SP of all selections whilst maintaining your strike rate.

Please somebody else check this as it's getting late and I've had a crap week.

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Pixie

"It's worth remembering that profit isn't profit until it's spent off the racecourse." -- Crash