Astrid Dannenberg

Inequality, communication, and the avoidance of disastrous climate change in a public goods game

International efforts to provide global public goods often face the challenges of coordinating national contributions and distributing costs equitably in the face of uncertainty, inequality, and free-riding incentives. In an experimental setting, we distribute endowments unequally among a group of people who can reach a fixed target sum through successive money contributions, knowing that if they fail, they will lose all their remaining money with 50% probability. In some treatments, we give players the option to communicate intended contributions. We find that inequality reduces the prospects of reaching the target but that communication increases success dramatically. Successful groups tend to eliminate inequality over the course of the game, with rich players signaling willingness to redistribute early on. Our results suggest that coordination-promoting institutions and early redistribution from richer to poorer nations are both decisive for the avoidance of global calamities, such as disruptive climate change.

Climate negotiations under scientific uncertainty

How does uncertainty about “dangerous” climate change affect the prospects for international cooperation? Climate negotiations usually are depicted as a prisoners’ dilemma game; collectively, countries are better off reducing their emissions, but self-interest impels them to keep on emitting. We provide experimental evidence, grounded in an analytical framework, showing that the fear of crossing a dangerous threshold can turn climate negotiations into a coordination game, making collective action to avoid a dangerous threshold virtually assured. These results are robust to uncertainty about the impact of crossing a threshold, but uncertainty about the location of the threshold turns the game back into a prisoners’ dilemma, causing cooperation to collapse. Our research explains the paradox of why countries would agree to a collective goal, aimed at reducing the risk of catastrophe, but act as if they were blind to this risk.

Social norms as solutions

Policies may influence large-scale behavioral tipping Climate change, biodiversity loss, antibiotic resistance, and other global challenges pose major collective action problems: A group benefits from a certain action, but no individual has sufficient incentive to act alone. Formal institutions, e.g., laws and treaties, have helped address issues like ozone depletion, lead pollution, and acid rain. However, formal institutions are not always able to enforce collectively desirable outcomes. In such cases, informal institutions, such as social norms, can be important. If conditions are right, policy can support social norm changes, helping address even global problems. To judge when this is realistic, and what role policy can play, we discuss three crucial questions: Is a tipping point likely to exist, such that vicious cycles of socially damaging behavior can potentially be turned into virtuous ones? Can policy create tipping points where none exist? Can policy push the system past the tipping point?

The role of the government in adaptation to climate change

Given the scarcity of resources, an economic approach is necessary in order to determine an optimal strategy of adaptation to climate change. In this paper we develop an economic framework for the study of adaptation which allows distinguishing between decentralised adaptation by private agents, on the one hand, and centralised adaptation measures by the government, on the other hand. The paper is in two parts: in the first we present the neoclassical view of adaptation policy, which is based on the paradigm of market failure. In the second part we deal with challenges and complements of the neoclassical view arising from the introduction of equity principles, security of supply concerns, and a polycentric approach to the provision of public goods. The analysis is illustrated with examples of adaptation measures in Germany.

Three necessary conditions for establishing effective Sustainable Development Goals in the Anthropocene

The purpose of the United Nations-guided process to establish Sustainable Development Goals is to galvanize governments and civil society to rise to the interlinked environmental, societal, and economic challenges we face in the Anthropocene. We argue that the process of setting Sustainable Development Goals should take three key aspects into consideration. First, it should embrace an integrated social-ecological system perspective and acknowledge the key dynamics that such systems entail, including the role of ecosystems in sustaining human wellbeing, multiple cross-scale interactions, and uncertain thresholds. Second, the process needs to address trade-offs between the ambition of goals and the feasibility in reaching them, recognizing biophysical, social, and political constraints. Third, the goal-setting exercise and the management of goal implementation need to be guided by existing knowledge about the principles, dynamics, and constraints of social change processes at all scales, from the individual to the global. Combining these three aspects will increase the chances of establishing and achieving effective Sustainable Development Goals.

On the Formation of Coalitions to Provide Public Goods – Experimental Evidence from the Lab

The provision of public goods often relies on voluntary contributions and cooperation. While most of the experimental literature focuses on individual contributions, many real-world problems involve the formation of institutions among subgroups (coalitions) of players. International agreements serve as one example. This paper experimentally tests theory on the formation of coalitions in different institutions and compares those to a voluntary contribution mechanism. The experiment confirms the rather pessimistic conclusions from the theory: only few players form a coalition when the institution prescribes the full internalization of mutual benefits of members. Contrary to theory, coalitions that try to reduce the freeriding incentives by requiring less provision from their members, do not attract additional members. Substantial efficiency gains occur, however, both along the extensive and intensive margin when coalition members can each suggest a minimum contribution level with the smallest common denominator being binding. The experiment thereby shows that the acceptance of institutions depends on how terms of coalitions are reached.

What Does Europe Pay for Clean Energy? – Review of Macroeconomic Simulation Studies

This paper analyses the macroeconomic costs of environmental regulation in European energy markets on the basis of existing macroeconomic simulation studies. The analysis comprises the European emssion trading scheme, energy taxes, measures in the transport sector, and the promotion of renewable energy sources. We find that these instruments affect the European economy, in particular the energy intensive industries and the industries that produce internationally tradeable goods. From a macroeconomic point of view, however, the costs of environmental regulation appear to be modest. The underlying environmental targets and the efficient design of regulation are key determinants for the cost burden.

Coordination Under Threshold Uncertainty in a Public Goods Game

We explored experimentally how threshold uncertainty affects coordination success in a threshold public goods game. Whereas all groups succeeded in providing the public good when the exact value of the threshold was known, uncertainty was generally detrimental for the public good provision. The negative effect of threshold uncertainty was particularly severe when it took the form of ambiguity, i.e. when players were not only unaware of the value of the threshold but also of its probability distribution. Early signaling of willingness to contribute and share the burden equitably helped groups in coping with threshold uncertainty.

Coalition Formation and Voting in Public Goods Games

This study experimentally examines the voluntary formation of coalitions to provide a public good when the coalition members use different voting schemes to determine their commitment. To this end, unanimity, qualified majority voting, and simple majority voting are compared with respect to the resulting public good provision level and social welfare. At first sight, in line with theoretical predictions, the experiment shows that a change in the voting scheme implemented in a coalition does not significantly change the social welfare. However, changing the majority required to determine the coalition efforts alters the depth and breadth of cooperation; coalitions under the unanimity rule are relatively large and implement moderate effort levels while coalitions with majority voting implement high effort levels but attract only a few participants.

Leading by example versus leading by words in voluntary contribution experiments

This paper compares different forms of leadership in their ability to improve cooperation in a public goods experiment. Leaders either contribute before the others (leading by example) or make a non-binding pledge before all players contribute simultaneously (leading by words). The exogenously imposed leadership is then compared to an endogenous setting where players can choose if and how they want to lead. The results show that in both settings leading by example has significant positive effects on cooperation while leading by words only has small effects as compared to situations without leadership. However, only few subjects choose to lead by example when they have the choice. The majority choose to lead by words or do not want to lead at all. The results also show that leading by example is associated with an institutional effect (players increase their contributions when they have to lead by example) and a selection effect (players who choose to lead by example are particularly cooperative).