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Favourite-longshot bias

The favourite-longshot bias is the finding that bets on long shots lose more per unit staked than bets on favourites: they win less often than their odds imply.

Example

An outsider at 21.00 implies 4.8%. If outsiders like it win 3.5% of the time, a stake on them loses about a quarter of itself on average.

Go further

The favourite-longshot bias explainedThe full explainer, on the blogImplied probability calculatorThe chance each price implies, the bookmaker’s margin and the fair odds without it.

Related terms

Bookmaker margin (overround)A bookmaker’s margin, or overround, is how far a market’s implied probabilities add up past 100%. It is the built-in edge the bookmaker holds over the bettor.Implied probabilityImplied probability is the chance a price represents: 1 divided by the decimal odds. It includes the margin, so a market’s prices add up to more than 100%.