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Expected value

Weight each result by how often it happens and add them up: the way to compare any two poker decisions.

8 steps, as text. step through the interactive version →

  1. 01, open this step in the interactive version

    You can pay $20 to play for a $100 pot. You’ll win about one time in four.

  2. 02, open this step in the interactive version

    Two things can happen. You win $100 a quarter of the time, or lose $20 the rest of the time.

  3. 03, open this step in the interactive version

    Weight each result by how often it happens, then add them up. That’s expected value.

  4. 04, open this step in the interactive version

    Here it’s +$10. You will never win exactly $10 on a hand. You win $100 or lose $20.

  5. 05, open this step in the interactive version

    is what you average if you play the same spot many times. Watch 100 hands.

  6. 06, open this step in the interactive version

    Some stretches lose money. Over enough hands, the average settles near +$10 per hand.

  7. 07, open this step in the interactive version

    Folding always earns exactly $0. Calling earns +$10 on average. Pick the bigger number: call.

  8. 08, open this step in the interactive version

    Change how often you win. Below one time in six, calling is worse than folding.