Originally Posted by Chrome Prince

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I did an exercise in the thousands of manually comparing the movements of TAB IAS and Betfair on favourites. I also tried two approaches in real time over a thousand bets (at the start of this thread).
What got me started was the Betfair Advantage Tool, and realising that the price comparison was to a degree flawed, I wanted to compare the best and worst prices and the actual fluctuations rather than just the final price available on Betfair.

As this data is not available in Betfair's historical data, I had to do it all manually (ugh).

But I did only record various prices, not every price (that would be near impossible).
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