Suppose you find a tipster who successfully tips 6 line bets out of 10. Does this guarantee they have an edge over the market? What if they correctly tip 60 out of 100? Or 600 out of 1,000? This calculator determines whether the betting performance was due to an actual edge over the market rather than just luck.
Both tests measure how likely it is that the difference between the actual betting performance and the expected performance was due to chance.
With this tool you can analyse the tipster’s historical performance before you make a purchase decision. You can also measure your own betting performance or that of a model you’ve developed. The calculator also serves as an educational tool. You can play around with win frequencies and total bet counts to see their impact on the calculated metrics.
How to prepare the required data
To use the calculator you will first need to tally the number of wins, the number of total bets and the expected win count.
The total bets count is the total number of winning and losing bets. Refunded bets (pushes) should be ignored.
The actual win count is simply the number of bets that won.
The expected win count equals the sum of the reciprocals of the decimal odds for all of your winning and losing bets. For example, if the decimal odds are 4.00, the expected win count for that bet is 1/4.00 = 0.25. This gives you the associated probability of each bet winning (ignoring bookmaker margins, which the calculator factors in later). Acquiring this figure will require the use of a spreadsheet. Below is a screenshot of a spreadsheet to illustrate how to obtain the required values.
The final field is the bookmaker margin. This is used to adjust the reciprocals of the odds to obtain the fair probabilities of winning. For example, decimal line odds are usually around 1.90 or 1.91, which equate to fair odds of 2.00 for a 50% chance of winning. The default value of 0.05 equates to line odds of 1.9048.
Betting Performance Calculator
Requirements: total bets > actual wins > expected wins.