Gamblers fallacy

Self Assessment

The Gambler's Fallacy is a cognitive bias that leads individuals to believe that future probabilities are altered by past events, despite the events being independent. It is the mistaken belief that if something happens more frequently than normal during a given period, it will happen less frequently in the future, or vice versa.

How it works

This fallacy arises from the incorrect assumption that random processes are self-correcting. People confuse the law of large numbers, which states that as a sample size grows, the sample mean will get closer to the population mean, with the belief that deviations from average outcomes in a short sequence of random events means future deviations will balance out immediately.

Examples

  • A classic example is flipping a fair coin. After getting heads five times in a row, an individual might believe that the next flip is more likely to result in tails, despite each flip being a separate event with a 50% chance for heads or tails.
  • Another instance is in lottery draws. If certain numbers haven't been drawn in a while, some people believe those numbers are 'due' to appear, affecting their choice when selecting lottery numbers.

Consequences

Believing in the Gambler's Fallacy can lead to poor decision-making in gambling, investments, and even personal life. It can cause individuals to place unwarranted bets based on supposed 'patterns' and 'hot streaks', often resulting in financial loss, increased risk-taking, and decision paralysis.

Counteracting

To counteract the fallacy, it's important to understand the nature of randomness and independence in events. Education about probability and statistical independence can help. Cognitive-behavioral strategies can also be used to challenge erroneous beliefs and encourage a more analytical approach to risk and probability.

Critiques

Some critics argue that what is often classified as the Gambler's Fallacy may be rational in contexts where individuals lack information, such as uncertain complex systems, where perceived patterns might sometimes result from underlying factors not yet understood. Nonetheless, in strictly independent random processes, the fallacy holds no ground.

Fields of Impact

Also known as

Monte Carlo Fallacy
Fallacy of the Maturity of Chances

Relevant Research

  • What's next? Judging sequences of binary events

    Oskarsson, A. T., Van Boven, L., McClelland, G. H., & Hastie, R. (2009)

    Psychological Bulletin, 135(2), 262-285

  • The 'Gambler's Fallacy' in Lottery Play

    Clotfelter, C. T., & Cook, P. J. (1993)

    Management Science, 39(12), 1521-1525

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