Context effects and the temporal stability of stated preferences

Area of Science:

• Behavioral Economics
• Consumer Psychology
• Ethical Consumption Studies

Background:

• Stated preference studies assume respondent answers reflect true, stable preferences.
• Validity and reliability are crucial for the credibility of these studies.
• Ethical consumption choices, particularly for products with political implications, require careful examination.

Purpose of the Study:

• To test the validity and reliability assumptions of stated preference studies.
• To examine how question context affects preferences for ethical products.
• To assess the temporal stability of preferences amidst external events.

Main Methods:

• A choice experiment was used to measure preferences for Israeli, Palestinian, and organic products.
• A web survey in Germany manipulated question order (attitudinal questions before/after choice tasks).
• The experiment was replicated ten months later, following a major Israeli-Palestinian conflict.

Main Results:

• A directional context effect was observed: placing attitudinal questions first increased the valuation of Israeli, Palestinian, and Peace Products.
• Organic product valuation decreased when discriminatory attitudes were surveyed beforehand, suggesting an anti-discrimination norm.
• Despite a significant geopolitical event, stated preferences demonstrated high temporal stability.

Conclusions:

• Stated preference studies exhibit high reliability and temporal stability.
• Question context can influence stated preferences, highlighting the need for careful survey design.
• Findings support the use of stated preference data by decision-makers in policy and business.