expected-value

Expected value (EV) is the weighted average gain or loss of a decision across all possible outcomes. In poker, EV is the single objective standard for whether a decision is correct.

Detailed Explanation

Formula:

EV = Σ (probability of each outcome × net gain/loss of each outcome)

Any poker decision can be written as EV. Comparing "call" vs "fold":

• EV(fold) = 0 (baseline, no further change)
• EV(call) = win probability × pot won + loss probability × chips lost

If EV(call) > 0, calling beats folding; if EV(call) < 0, folding is better.

+EV decisions can lose in the short term, -EV decisions can win in the short term — that's variance. But over the long run, the accumulation of +EV decisions necessarily converges to positive results.

Common Use Cases

• Every decision: EV thinking is the universal framework for poker decisions
• Bankroll management: long-term EV + variance tolerance together determine the stakes you can play
• Mental training: separating "decision quality" from "single-hand results" to avoid result-oriented thinking

Common Mistakes

• Judging EV by results: a single win doesn't prove +EV; a single loss doesn't prove -EV
• Substituting equity for EV: equity is one input to EV, not EV itself
• Ignoring the opponent's range: EV calculations depend on the opponent's range estimate — wrong range estimates produce wrong EV