How can we apply expected value to help us betting on football? An excellent way to apply the EV mechanism and its formula to football betting is by taking a look at the opening & closing market odds. You can say that, on average closing, market odds are closer to the true odds than the opening market ones. Coming from that, it would be safe to assume that the difference between these two odds is the actual expected value that the market initially had. Nevertheless, it is not always true that either type of odds is correct or incorrect. We only say that calculating the difference between the two can be used as a reasonable estimation of the market EV, especially when we never know true odds in reality. Thus, let us change the above EV equation and adapt it for the new calculations. The new formula should look the following way:
Expected Value = (Openning Odds / Closing Odds) - 1
You must also keep in mind that both odds can be shorter than the true odds, as well as one of them being shorter & the other one being longer, and vice versa. So, please, be aware of that before calling this method foolish. Nevertheless, while you might face such situations down the road, the above calculations should give you a solid estimation of the amount of Expected Value possessed by the market.
So, how can punters use this method? Your first step in building your working model based on this approach will be data collection. It would be perfect to get access to a particular market’s historical data (opening & closing odds). Of course, the bigger the set, the better! Then, you would need to apply the above formula and calculate the expected value for each chase. That will help you get the idea about how much EV there was in the past, as well as its average. Analyse it and focus on the results with the EV greater than 0%. Estimate what share of the odds had a positive EV, and divide it into smaller segments based on the EV % range. For example, you can do >0%, >2%, >10%, etc. A little spoiler for you, the greater your EV will get, the smaller share of the odds will actually have it, decreasing exponentially.
Hopefully, you will master this method and achieve better results in the future with the help of it. Unfortunately, this method requires some time to get started since it only tells you about how much EV there was after the market closure, or at least at its very closure. Anyways, that would be too late to place a bet at the initial market odds. However, establishing a good model on the market will help you make quite accurate forecasts & beat your online bookmaker right at the market opening. Good luck!