Wide of the mark: Evidence on the underlying causes of overprecision in judgment

• We test the assumption that overprecision is due to narrow subjective probability distributions.
• Subjective probability distributions are, in fact, too wide.
• Findings contradict prevailing consensus on causes of overprecision.
• Underprecision is reduced by experience.
• Underprecision is reduced by framing the uncertainty as epistemic (vs. aleatory).