Betting on Betfair can be as much about when to bet as what to bet. Exactly when you strike your bet can have a significant impact on your overall profit or loss. You may have typically tested a strategy to Betfair SP as these are the commonly available numbers. Betting to Betfair SP however runs the risk that you may cannibalise your price with the stake you place, especially at longer prices. To avoid this many people try to get close or better than BFSP by betting at some other point in time.
Beating Betfair SP can be quite difficult as the following numbers from 2012 show. Taking a sample of 2,488,767 data price points between 5 minutes and the official off time 42% proved to be above the official Betfair SP whilst 57% where below the SP (decimal places ignored). The price checks were taken for all horses showing at odds below 10.0 and where taken at 5 second intervals down to the official off time.
Perhaps if we are backing horses then the losing horses don’t really matter. Who cares if we beat SP on our losing bets. Re examining the data for winning horses shows a slightly improved picture but still one in which Betfair SP works out best. 486,852 data points of which 46% where above the BFSP and 53% would have been better off or at least equal to BFSP.
Losing bets not surprisingly move slightly the other way with 42% beating BFSP and 57% proving to be short change. Of course this does not necessarily mean that your particular betting method will follow the same pattern. If you have an edge it could be that that edge is eroded as time progresses towards the off time. You won’t know this unless you back test your selections against BFSP and some other time point. An easier strategy would be to strike small token bets at set time points on all your selections at easy identifiable stakes and then over a given period of time download your Betfair account data into a spreadsheet and analyse the data. For example you could place £2.99 additional bets at 10 minutes to the off. In time this will give you a fully R4 adjusted comparison between your normal full stake bet and the varied off time bet.