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Case file

Availability Heuristic

Filed under
Too Much Information
Also recorded as
Availability bias

The charge

We judge how likely or common something is by how easily examples come to mind, not by actual frequency. Vivid or recent cases then feel more representative than they really are.


How it operates

Memory retrieval is fluency-based: events that are emotional, recent, or heavily publicized are easier to recall, and the mind mistakes recall ease for evidence. That shortcut is fast, but it skews probability judgments.

Logged incidents

  1. Incident 01

    After a well-publicized outage at a competitor, a leadership team overinvests in reliability features while neglecting quieter but more common churn drivers.

  2. Incident 02

    An investor avoids airline stocks after seeing multiple crash stories on the news, even though the broader risk picture has not materially changed.

  3. Incident 03

    A hiring manager overrates a candidate from a famous company because success stories from that brand are easier to remember.

What to watch for

Ask yourself: 'Am I judging frequency or risk from the easiest examples I can recall rather than from actual numbers?'

Recommended action

Use reference class forecasting and a base-rate check before estimating risk or impact. Force yourself to look at the full distribution, not the most memorable cases.

Known associates

Source of record

en.wikipedia.org

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