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Gambler’s fallacy

Believing that an independent random outcome is due because the opposite outcome occurred repeatedly.

Published 04 August 2026Updated 04 August 2026

The gambler’s fallacy assumes that short runs must quickly balance themselves, such as treating a coin as more likely to land heads after several tails. When trials are independent, earlier outcomes do not change the probability of the next one.

Sources

Judgment under Uncertainty: Heuristics and Biases

Science / 1974 / Paper

Classic heuristics and biases paper.