"Strategic Delegation in the Formation of International Environmental Agreements" with Ralph Winkler (2022)
(published in European Economic Review)
We reassess the well-known “narrow-but-deep” versus “broad-but-shallow” trade-off in international environmental agreements (IEAs), taking into account the principal-agent relationship induced by the hierarchical structure of international policy. To this end, we expand the modest coalition formation game, in which countries first decide on whether to join an agreement and then decide on emissions by a strategic delegation stage. In the weak delegation game, principals first decide whether to join an IEA, then delegate the domestic emission choices to an agent. Finally, agents in all countries decide on emissions. In countries not joining the IEA, agents choose emissions to maximize their own payoff, while agents of countries joining the IEA set emissions to internalize some exogenously given fraction of the externalities that own emissions cause on all members of the IEA. In the strong delegation game principals first delegate to agents, which then decide on membership and emissions. We find that strategic delegation crowds out all efforts to increase coalition sizes by less ambitious agreements in the weak delegation game, while in the strong delegation game the first-best from the principals’ point of view can be achieved.
This paper examines the role of domestic elections and political polarisation in shaping international environmental agreements and how electoral dynamics may explain the limited success of current climate cooperation. I focus on two key factors: the impact of domestic electoral pressure on international policy decisions and the mismatch between short election cycles and long-term treaty commitments. Using a 4-stage game modelling a bilateral environmental agreement, I analyse how incumbents strategically balance policy preferences with reelection prospects. Results show that while a \textit{green} incumbent is often forced to temper their ambitions, a \textit{brown} incumbent faces fewer electoral constraints, explaining why stringent policies are harder to achieve. Nonetheless, electoral pressure can moderate policies, producing outcomes more aligned with the preferences of the median voter. I finally discuss how political polarisation, particularly in two-party systems, adds complexity to international cooperation on global public goods.
"Assessing Private Solutions to Collective Action Problems in a 34-Nation Study [Preprint]" with Eugene Malthouse and co-authors (CDMCL) (submitted)
Collective action problems emerge when individual incentives and group interests are misaligned, as in the case of climate change. Individuals facing collective action problems are often considered to have two options: contribute towards a public solution or free-ride. But they might also choose a third option of investing in a private solution such as local climate change adaptation. Experimental research on the dynamics of collective action problems has rarely accounted for the availability of private solutions and has been conducted in single-country contexts (with few exceptions), thereby lacking generalisability. Here we introduce an experimental collective action problem featuring wealth inequalities, public and private solutions, and participants from 34 countries. We show that participants endowed with higher income choose the private solution almost twice as often as those endowed with lower income. This finding cannot be explained by different sources of wealth (luck vs. merit) or by cultural or economic background. We also show that participants endowed with higher income contribute a lower proportion of their wealth towards public solutions, with inequality increasing in every country. Lastly, we report that early contributions represent a universal pathway to public solution provision. Our findings highlight how the "private solution problem" can act as a ubiquitous obstacle in modern collective action problems in which the rich can afford to rely on private solutions while the poor remain unprotected.
"Efficiency versus Equity in a Threshold Public Goods Game" with Ralph Winkler (draft available upon request)
We analyse a threshold public goods game in which players have varying benefits from public goods provision, motivated by the existence of large heterogeneities between countries in international environmental cooperation. The setup chosen specifically allows for an analysis of the trade-off between efficiency and equity. We choose a preference specification allowing for a variety of other-regarding preferences and hypothesize that benefit symmetry among players facilitates coordination due to converging focal points of efficiency and equity. Increasing degrees of asymmetry lead to diverging focal points, rendering cooperation more difficult. Our theoretical predictions are supported by preliminary experimental evidence. We find that provision is most frequent when players are symmetric. While increasing the degree of asymmetry does not significantly hamper provision success, contributions become more volatile the more heterogeneous players are. Analysing how players share contribution costs, we see that the extent of asymmetry is not salient, leading to relatively constant burden-sharing across treatments despite varied levels of inequity.
"Investing in Tomorrow: Understanding the Dynamics of a Green Transition" with Maria Alejandra Erazo
This project investigates the behavioural and strategic factors influencing the adoption of novel technologies, particularly in settings where early investments are critical but uncertain. By combining theoretical and experimental methods, we examine how individuals and groups navigate the trade-offs between immediate returns from established technologies and the long-term benefits of innovative alternatives. The project also explores how strategic uncertainty and policy risks, such as shifts in regulatory environments, impact investment decisions. Ultimately, we aim to provide insights into fostering cooperation, accelerating technological transitions, and designing effective policy frameworks.
"Solar Geoengineering with Trade Sanctions" with Daniel Heyen & Alessandro Tavoni
In this project, we aim at contributing to the understanding of political economy considerations around Solar Geoengineering (SG) technologies. Using the public gob feature of SG and the well known insight that trade sanctions might help stabilise environmental policies, we show that the prevalent concern in the literature about excessive SG deployment might be weakened when accounting for political economy context.
"Political Support for Carbon Taxation with Behavioural Agents"
This project aims at investigating how the presence of behavioural voters might be an explanatory factor for the political unpopularity and infeasibility of carbon taxes. Could it explain why some voters are, seemingly, voting against their own self-interests regarding environmental regulation? If so, what are policy implications? If (some) voters are behavioural, they potentially i) do not rationally react to the tax and ii) do not correctly assess their welfare under carbon taxation. As a consequence, it can then happen that a regulatory policy theoretically capable of winning a majority (e.g. the optimal Pigou tax), is rejected at the ballot. In order to determine a potential second-best carbon tax, I suggest an optimal carbon tax game accounting for the behavioural biases assumed.
"Individual Emission Record and Climate Dividend Preferences" with Christin Hoffmann & Niklas Ziemann
This project examines how information about individuals’ carbon emission records influences their preferences for different climate dividend models — a topic actively debated in current policy discussions. As several countries consider implementing climate dividends to offset higher carbon taxes, understanding whether people favour equal distribution or compensation based on individual carbon burdens is crucial. Through a consequential laboratory experiment, we aim to provide insights into how transparency about personal emissions shapes public support for climate policies.