Don't trust Betfair SP data
 

Don't trust that the Betfair historical data is correct.
I downloaded a significant sample size (12 months) which showed a significant edge with filters on a daily basis, in reality I've been using Gruss Betting Assistant and set it up correctly. After a month of betting on every race with the filters it shows a loss. I took commission into consideration, so it's not that.
Where they are getting their data from certainly isn't from the actual Betfair SP. Something is really off in a big way!

Chrome

Did you account for deductions for late scratchings ? This is where most people get screwed up and yeah it makes a huge difference.

Also did you also account for the different commissions per state? And commission is only paid on winning markets. Losses in other markets do not offset your commission to pay.

Also one of my golden rules is never use historical data provided by anyone, always collect it yourself even if it takes months or a year to collect enough to analyse.

I have no idea if the history files are correct as I collect my own numbers but BSP is very hard to beat for the average punter (even those who know what they are doing). BSP is very efficient.

Hi UB,
Yes, I accounted for deductions for late scratchings.
I used a flat 10% commission deduction even though that is the worst case scenario. Yes, BSP is very hard to beat, but the filters I had in place did show a profit long term.