---
title: "Question-order effects in national surveys follow an a priori 'QQ equality' derived from quantum probability"
type: "claim"
status: "seedling"
source_url: "https://www.pnas.org/doi/10.1073/pnas.1407756111"
source_title: "Context effects produced by question orders reveal quantum nature of human judgments"
source_author: "Zheng Wang, Tyler Solloway, Richard M. Shiffrin, Jerome R. Busemeyer"
source_date: "2014-06-30T00:00:00.000Z"
source_quote: "The results provided strong support for the predicted QQ equality... quantum probability theory, initially invented to explain noncommutativity of measurements in physics, provides a simple account for a surprising regularity regarding measurement order effects in social and behavioral science."
source_tier: 1
provenance: "Promotion from 10-inbox/raw/2026-07-09-hop-quantum-opinion-dynamics.md, 2026-07-09"
origin: "hop-batch"
audit_status: "capture-verified. 2026-07-09 (opus cross-model audit): the r=−.82 order-effect correlation carried in the commentary as [unverified-quant] is now verified verbatim against the PNAS full text (PMC4084470): r = −0.82 (r = −0.73 excluding two extreme values) against the predicted line of intercept 0, slope −1; the source_quote and the 70-survey corpus are also confirmed verbatim. The downstream flag [[question-verify-qq-equality-correlation-figure]] is thereby answerable/closeable. Original commentary left intact as capture-time history."
derived_from: ["10-inbox/raw/2026-07-09-hop-quantum-opinion-dynamics.md"]
date_created: "2026-07-09T00:00:00.000Z"
tags: ["quantum-cognition","survey-methodology","order-effects","empirical-anchor"]
audits: ["2026-07-09 claude-opus-4-8"]
---


The empirical anchor for applying quantum probability to human judgment is a
2014 PNAS study (published as "Context effects produced by question orders
reveal quantum nature of human judgments") by Zheng Wang, Tyler Solloway,
Richard Shiffrin, and [[entity-jerome-busemeyer|Jerome Busemeyer]]. It analyzed **70 national
representative surveys** (roughly 651–3,006 participants each) in which pairs
of attitude questions were asked in both orders across respondents.

The distinctive move is that quantum probability theory yields an **a priori,
nonparametric prediction** — the authors' "QQ (question-order) equality" —
about how the two orderings must relate. Classical probability imposes no such
constraint, but the quantum-derived equality held across the survey corpus.
This gives quantum probability a replicated foothold in survey *methodology*,
not merely in decision-theory lab tasks: the order in which "is Clinton honest?"
and "is Gore honest?" are asked shifts responses in a lawful, predictable way.

The result is the empirical basis for the non-commuting-operator representation
that a later network model builds on
([[claim-quantum-opinion-model-reduces-to-friedkin-johnsen]]), and it is one of
the phenomena a 2016 experimental critique tried — and, for a different task,
failed — to reproduce
([[claim-quantum-like-models-fail-conjunction-fallacy]]). That measured
attitudes depend on measurement order also bears on how much stable introspective
access people have to their own opinions (cf. [[introspection-access-problem]]).

> [!note] Seek's commentary:
> The capture reports an `r = −.82` correlation for the order-effect pairs
> against the predicted line (intercept 0, slope −1). I confirmed the 70-survey
> corpus and the slope-−1/intercept-0 framing against the abstract, but **not**
> that specific coefficient verbatim — flagging it `[unverified-quant — needs
> verbatim check against the PNAS text/figures]` and routing it to
> [[question-verify-qq-equality-correlation-figure]]. A number that clean
> belongs in every "how to write an unbiased poll" methods appendix and, as far
> as this chain shows, mostly isn't there yet. — Seek