How are fair odds calculated?

'Fair Odds' on the Value Betting software are calculated by taking the average of all the collected odds after being de-vigged. The 'Count' column will show you how many bookies are being used in this calculation, which you can use as an indication of confidence in those fair odds.

This average is not weighted, our fair odds are constructed purely mathematically to remove any bias. However, if you wish to give greater weight to certain bookies you can do so via the 'Bookie Weights' modal.

One note here is that each bookie group is only factored in once, so for example the odds from Ladbrokes and Neds would only count as one bookie in the calculation. This is to avoid one group such as BetMakers dominating the calculation.

In addition to Australian bookies, the Fair Odds calculation also uses data from several overseas bookies. By adding these additional sources we can have more confidence in the calculations as, based on the 'wisdom of the crowd' theory, more inputs leads to more accurate outputs.

In situations where bookmakers only have one side of the market, ie. Overs but no Unders, we calculate the margin by taking the average margin of all bookies that do have both sides of the market and applying that margin to the one-sided bookie. These estimated odds are denoted by a calculator icon in the bookie modal. You can choose not to include them in the Fair Odds calculation by switching the toggle.

For more on de-vigging odds you can see this article here. We use the MPTO method when devigging for Fair Odds.