Alonso-Paulí, EduardBalart, PauEzquerra, LaraHernández Arenaz, Íñigo2025-05-062025-05-062025-05-02Alonso-Paulí, E., Balart, P., Ezquerra, L., Hernandez-Arenaz, I. (2025). Using pledges to improve the effectiveness of environmental information campaigns: The case of biowaste recycling. Proceedings of the National Academy of Sciences, 122(18), 1-10. https://doi.org/10.1073/pnas.2414578122.0027-842410.1073/pnas.2414578122https://academica-e.unavarra.es/handle/2454/54072Through a field study (N = 1,519) that uses a technology to record real-time data on waste sorting, we find that offering the opportunity to sign a pledge increases the effectiveness of an environmental campaign. With a timespan of over four years, the pledge increased waste sorting participation by 4.55 to 5.10 percentage points (SD = 0.1997). The effect is greater immediately after the campaign (around 9 to 10 pp during the first 15 wk), but it remains sizable and statistically significant 150 to 210 wk after signing (3.11 to 4.45 pp). Continue Readingapplication/pdfeng© 2025 the Author(s). This article is distributed under Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0.EnvironmentSoft commitmentRecyclinginfo:eu-repo/semantics/article2025-05-06info:eu-repo/semantics/openAccess