Implied probability in sports betting
Implied probability translates odds into an approximate percentage. It helps show what probability a market price represents before comparing it with an independent estimate.
How to convert odds into probability
With decimal odds, the basic formula is: implied probability = 1 / odds.
Example: odds 2.00 = 50%. Odds 1.50 ≈ 66.7%. Odds 1.80 ≈ 55.6%.
What it really represents
Implied probability is not an objective forecast. It is a mathematical translation of the available price, and bookmaker margin can be embedded in that price.
Why it matters for value analysis
If an independent estimate is higher than the implied probability, there may be a favorable difference. That gap is the foundation for concepts such as edge and expected value.
Practical example
If odds of 1.70 imply about 58.8% and a model estimates 66%, the gap is roughly 7.2 percentage points. That difference should still be evaluated alongside model quality and match context.
How SignalXI uses it
SignalXI compares its estimated probability with available price to measure edge and expected value before considering a recommendation.
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