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Licensed Unlicensed Requires Authentication Published online by De Gruyter Oldenbourg September 9, 2022

A Model United Nations Experiment on Climate Negotiations

Elisa Hofmann ORCID logo, Lucas Kyriacou ORCID logo and Klaus M. Schmidt ORCID logo


Weitzman, M.L. (2014. Can negotiating a uniform carbon price help to internalize the global warming externality? J. Assoc. Environ. Resour. Econ. 1: 29–49) proposed that focusing international climate negotiations on a uniform common commitment (such as a uniform carbon price) is more effective than negotiations on individual commitments (as in the Paris agreement) in achieving ambitious climate action. We put this hypothesis to an experimental test by simulating international negotiations on climate change in collaboration with Model United Nations associations. This novel experimental format combines some of the advantages of lab and field experiments. Our results offer support for Weitzman’s hypothesis and indicate that negotiating a common commitment on a uniform carbon price may yield higher emission reductions in the long run and more participation than individual commitments à la Paris.

JEL Classification: C81; C93; F51; H87; Q54

Corresponding author: Klaus M. Schmidt, Department of Economics, University of Munich, Ludwigstraße 28, D-80539 Munich, Germany, E-mail:
We would like to thank Friedrich Breyer, Uwe Cantner, Ernst Fehr, Michael Gerfin, Jonas Meier, Axel Ockenfels, Doina Radulescu, Tobias Regner, Asri Özgümüs, Wladislaw Mill, Ralph Winkler, the editor and two anonymous referees for helpful comments and suggestions. Financial support by Deutsche Forschungsgemeinschaft through CRC TRR 190 (project number 280092119) is gratefully acknowledged. Tanja Mitric, Timothy Rabozzi, Friederike Reichel, and Gabriel Vollert provided excellent research assistance. Moreover, we would like to thank the following MUN Associations for their support: Model United Nations University of Bern, ETH Model United Nations, MUN Team UZH, Model United Nations TU Munich e.V., MUNAM e.V., Model United Nations Mannheim e.V., Cologne MUN Society e.V., and United Nations Hochschulgruppe Tübingen.

Funding source: Deutsche Forschungsgemeinschaft

Award Identifier / Grant number: CRC TRR 190, project number 280092119

  1. Article Note: This article is part of the special issue “A New Decade of Research on the Economics of Climate Change: Towards an Integrated View on a Sustainable Use of the Biosphere” published in the Journal of Economics and Statistics. Access to further articles of this special issue can be obtained at


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Supplementary Material

The online version of this article offers supplementary material (

Received: 2021-10-28
Accepted: 2022-07-21
Published Online: 2022-09-09

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