Translate a probability + price into expected value per dollar staked. Positive EV = the math says you have an edge.
EV per $1 = p × (decimal_odds − 1) − (1 − p) where p = your estimated probability of winning
If EV per $1 is positive, the bet has long-run expected profit at that price — assuming your p is correct. Variance still applies; the bet can lose any individual time.
Pair this with the Kelly calculator to size the position.
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