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Expected Value

Expected value is a simplified estimate of value per share based on predicted probability, market price, and costs.

Definition

Expected value is a simplified way to translate a predicted probability and a market price into a per share value estimate. It depends strongly on cost assumptions.

Why it matters

EV helps you see whether a small probability edge is likely to be dominated by fees and execution frictions like effective spread.

Important limitations

• EV depends on how you model fees and whether you cross the spread.

• EV is not a guarantee and is not a recommendation.

• In thin markets, realized EV can diverge due to execution risk.

Common pitfalls

Treating EV as certainty: It is a model output based on assumptions.

Ignoring settlement rules: Settlement mechanics can dominate payoffs.