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Case file

Illusion of Validity

Filed under
Not Enough Meaning

The charge

Illusion of validity is feeling highly confident in a judgment because the evidence forms a neat story, even when it predicts poorly.


How it operates

Coherence is mistaken for accuracy. When cues fit together smoothly, confidence rises faster than actual predictive validity.

Logged incidents

  1. Incident 01

    A recruiter trusts a polished interview despite weak work-sample evidence.

  2. Incident 02

    A forecast deck feels convincing because all the slides align, even though the model has never been validated out of sample.

  3. Incident 03

    A VC backs a founder because pitch, pedigree, and charisma form one compelling narrative.

What to watch for

Ask: How accurate has this kind of judgment been on cases I did not already know the outcome of?

Recommended action

Use structured prediction, calibration, and out-of-sample validation instead of relying on subjective coherence.

Known associates

Source of record

en.wikipedia.org

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