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Case file

Gambler's Fallacy

Filed under
Not Enough Meaning
Also recorded as
Monte Carlo fallacy

The charge

Gambler's fallacy is expecting a random process to reverse soon because one outcome has happened repeatedly.


How it operates

People expect randomness to look locally balanced, so streaks feel like they must self-correct quickly.

Logged incidents

  1. Incident 01

    A trader thinks a stock is due for an up day after several down days.

  2. Incident 02

    A growth team expects conversion must bounce after a week of misses even though daily outcomes are noisy.

  3. Incident 03

    An executive assumes a sequence of bad candidate interviews means the next one is more likely to be great.

What to watch for

Ask: Are these events actually independent, or am I assuming short streaks must balance out?

Recommended action

Do an independence check and teach the team how random sequences naturally contain streaks.

Known associates

Source of record

en.wikipedia.org

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