Hasty Generalization

Drawing a broad conclusion from a small, unrepresentative, or anecdotal sample. Also called “jumping to conclusions” or “converse accident.”

Examples

  • “My grandfather smoked three packs a day and lived to 90. Smoking isn’t that bad.”
  • “I met two rude people from City X. Everyone from City X is rude.”
  • “This new hire was lazy. The whole generation has no work ethic.”
  • “I tried that restaurant once and it was bad. It’s a terrible restaurant.”
  • “Three studies show X. Therefore X is definitely true.” (ignoring 50 studies showing not-X)

Why It Happens

  • Availability heuristic: vivid/memorable examples feel more representative
  • Confirmation bias: we notice examples that fit our belief
  • Small sample sizes have high variance
  • Anecdotes feel more “real” than statistics

How to Counter

  • “What’s the sample size? Is it representative?”
  • “Are there systematic studies on this?”
  • “Could these examples be outliers?”
  • “What would a fair test of this claim look like?”