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  • Nature Human Behaviour

What We Can Learn from Five Naturalistic Field Experiments That Failed to Shift Commuter Behaviour

By: Ariella S. Kristal and A.V. Whillans
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Abstract

Across five field experiments with employees of a large organization (n = 68,915), we examined whether standard behavioural interventions (“nudges”) successfully reduced single-occupancy vehicle commutes. In Studies 1 and 2, we sent letters and emails with nudges designed to increase carpooling. These interventions failed to increase carpool sign up or usage. In Studies 3a and 4, we examined the efficacy of other well-established behavioural interventions: non-cash incentives and personalized travel plans. Again, we found no positive effect of these interventions. Across studies, effect sizes ranged from Cohen’s d = -0.01 to d =0.05. Equivalence testing, using study-specific smallest effect sizes of interest, revealed that the treatment effects observed in four out of five of our experiments were statistically equivalent to zero (P < 0.04). The failure of these well-powered experiments designed to nudge commuting behaviour highlights both the difficulty of changing commuter behaviour and the importance of publishing null results to build cumulative knowledge about how to encourage sustainable travel.

Keywords

Commuting; Field Experiments; Nudges; Behavior; Change

Citation

Kristal, Ariella S., and A.V. Whillans. "What We Can Learn from Five Naturalistic Field Experiments That Failed to Shift Commuter Behaviour." Nature Human Behaviour 4, no. 2 (February 2020): 169–176. (This article was featured on the cover as the lead article.)
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About The Author

Ashley V. Whillans

Negotiation, Organizations & Markets
→More Publications

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More from the Authors
  • Employee Stress Is a Business Risk—Not an HR Problem By: Marion Chomse, Lydia Roos, Reeva Misra and Ashley Whillans
  • Buying (Quality) Time Predicts Relationship Satisfaction By: A.V. Whillans, Jessie Pow and Joe J. Gladstone
  • Designing the Future of Work: Atlassian’s Distributed Work Practices By: Ashley Whillans and Gabriel Rondón Ichikawa
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