Law of small numbers

What it is

Expecting small samples to look like the whole population and drawing strong conclusions from a handful of cases.

Related

• Hasty generalization fallacy
  Hasty generalization is the law of small numbers in an argument: strong conclusions from tiny samples.
• Representativeness heuristic bias
  We expect small samples to resemble the population, which is a representativeness error.
• Clustering illusion bias
  Small samples naturally contain streaks and clusters that look meaningful.

Appears in

• The 99 thinking errors in Rolf Dobelli's The Art of Thinking Clearly#61: The law of small numbers

References

• Wikipedia: Law of small numbers en.wikipedia.org
• The 99 thinking errors in Rolf Dobelli's The Art of Thinking Clearly en.wikipedia.org
• Wikipedia: List of cognitive biases en.wikipedia.org
• Wikipedia: Cognitive bias codex en.wikipedia.org

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