Working paper · IRISP/2026/003
Perception Gaps: Approaches and Pitfalls
How the distance between public belief and the evidence can be measured honestly — and the traps that make published gaps larger or smaller than they are.
Abstract
A perception gap is the measured distance between what a public believes about a quantity and what the best available indicator says about it. This working paper reviews the principal approaches to measuring such gaps and the design choices on which the honesty of the measurement depends.
The paper gives particular attention to pitfalls: question wordings that invite estimation errors unrelated to belief, indicator choices that flatter or inflate the gap, aggregation that hides who actually holds the misperception, and comparisons across countries that ignore differences in the underlying indicators.
It closes with the checklist the institute will apply to its own gap measurements, so that a reader of any future IRISP® gap finding can verify that each pitfall has been addressed.
This publication is open access. It may be shared and reproduced freely with attribution to IRISP®. Read by a synthetic voice; the text is authoritative.