Limits to substitution between ecosystem services and manufactured goods and implications for social discounting

This paper examines implications of limits to substitution for estimating substitutability between ecosystem services and manufactured goods and for social discounting. Based on a model that accounts for a subsistence requirement in the consumption of ecosystem services, we provide empirical evidence on substitution elasticities. We find an initial mean elasticity of substitution of two, which declines over time towards complementarity. We subsequently extend the theory of dual discounting by introducing a subsistence requirement. The relative price of ecosystem services is non-constant and grows without bound as the consumption of ecosystem services declines towards the subsistence level. An application suggests that the initial discount rate for ecosystem services is more than a percentage-point lower as compared to manufactured goods. This difference increases by a further half percentage-point over a 300-year time horizon. The results underscore the importance of considering limited substitutability in long-term public project appraisal

Aufsätze in Nachhaltigkeitsökonomie: Ökonomische Verteilung und Bewertung, Umweltknappheit, und ethisches Verhalten

This doctoral thesis is based on seven chapters and six individual research articles and contributes to different strands of the economics literature, among others to environmental and resource economics, ecological economics, public economics, as well as behavioural and experimental economics. First and foremost, however, I see the thesis contributing to the emerging research area of sustainability economics. Specifically, I address some core aspects of the broader research agenda on sustainability economics. Chapter 2 studies how the economic valuation of non-marketed environmental goods depends on the distribution of income within a society, thus speaking to the intra-generational dimension of the human-nature relationship. Chapter 3, in turn, is concerned with allocative and distributive issues across generations. Specifically, it examines how society should allocate costs and benefits of public projects, such as those aimed at mitigating climate change, over time. Furthermore, chapters 4 and 5 address the role of `essential needs’ and `limitations’ as noted in the seminal Brundlandt definition of sustainability by studying to what degree scarce environmental goods and services indeed have human-made substitutes and complements if one takes subsistence consumption into consideration. Chapters 6 and 7 make use of economic experiments to study ethical behaviour of both fishermen and scientists, with a specific focus on honesty and truth-telling. While a better understanding of the behaviour of fishermen is directly relevant to the management of an important common pool resource, the question of whether scientists tell the truth is of fundamental importance for science at large and perhaps even more so for sustainability economics, which sees itself as a relevant science that not only follows a cognitive interest, but also a direct action or management interest in facilitating a transition towards a sustainable development

Truth-telling and the regulator: Evidence from a field experiment with commercial fishermen

Understanding what determines the extent to which economic agents tell the truth to their regulating authority is of major economic importance, from banking to environmental protection. To this end, we examine truth-telling of German commercial fishermen in an artefactual field experiment. Their regulator, the European Union (EU), has recently enacted a ban on discarding unwanted fish catches to the sea, without yet increasing monitoring activities. The regulator thus depends on fishermen's truth-telling, while standard economic theory predicts substantial self-serving dishonesty. Using a coin- tossing task, we test whether truth-telling in a baseline setting differs from behavior in two treatments that exploit fishermen's widespread ill-regard of the EU. We find that fishermen misreport coin tosses to their advantage, albeit to a lesser extent than standard theory predicts. Misreporting is stronger among fishermen in a treatment where they are faced with the EU flag, suggesting that lying towards their ill-regarded regulator is more substantial. Yet, some fishermen are more honest in a control treatment where the source of EU research funding is revealed additionally. Our findings imply that regulators can influence truth-telling behavior by means of their regulatory approaches and communication strategies

Discounting disentangled

The economic values of investing in long-term public projects are highly sensitive to the social discount rate (SDR). We surveyed over 200 experts to disentangle disagreement on the risk-free SDR into its component parts, including pure time preference, the wealth effect, and return to capital. We show that the majority of experts do not follow the simple Ramsey Rule, a widely used theoretical discounting framework, when recommending SDRs. Despite disagreement on discounting procedures and point values, we obtain a surprising degree of consensus among experts, with more than three-quarters finding the median risk-free SDR of 2 percent acceptable

Discounting disentangled

As the most important driver of long-term project evaluation, from climate change policy to infrastructure investments, the social discount rate (SDR) has been subject to heated debate among economists. To uncover the extent and sources of disagreement, we report the results of a survey of over 200 experts that disentangles the long-term SDR into its component parts: the pure rate of time preference, the wealth effect, and the real risk-free interest rate. The mean recommended SDR is 2.27 percent, with a range from 0 to 10 percent. Despite disagreement on point values, more than three-quarters of experts are comfortable with the median SDR of 2 percent, and over 90 percent find an SDR in the range of 1 to 3 percent acceptable. Our disentangled data reveal that only a minority of responses are consistent with the Ramsey Rule, the theoretical framework dominating discounting policy. Instead, experts recommend that governmental discounting guidance should be updated to deal with uncertainty, relative prices, and alternative ethical approaches

Professional identity and the gender gap in risk-taking: Evidence from a field experiment with scientists

The gender gap in risk-taking is often used to explain differences in labor market outcomes. Some studies, however, suggest that this gender gap does not extend to professional contexts. This paper examines potential drivers of the gender gap in risk-taking, comparing the professional context of academia to a private setting. We draw on identity economics, which posits that individuals form multiple identities that moderate behavior across contexts. In an online field experiment with 474 scientists we vary the salience of the professional or private identity. We find that the gender gap in risk-taking is mediated when the professional identity is salient. We identify the switching of identities by females as an explanation. Our results suggest that if the gender gap in risk-taking is driven by selection, the selection is not (only) along risk-aversion, but (also) along the ability to switch between identities and to adapt to prevailing norms. This provides new insights for the discussion on gender, risk-taking and labor market policies, and suggests an important role for mentoring programs

Climate economics support for the UN climate targets

Under the UN Paris Agreement, countries committed to limiting global warming to well below 2 °C and to actively pursue a 1.5 °C limit. Yet, according to the 2018 Economics Nobel laureate William Nordhaus, these targets are economically suboptimal or unattainable and the world community should aim for 3.5 °C in 2100 instead. Here, we show that the UN climate targets may be optimal even in the Dynamic Integrated Climate–Economy (DICE) integrated assessment model, when appropriately updated. Changes to DICE include more accurate calibration of the carbon cycle and energy balance model, and updated climate damage estimates. To determine economically ‘optimal’ climate policy paths, we use the range of expert views on the ethics of intergenerational welfare. When updates from climate science and economics are considered jointly, we find that around three-quarters (or one-third) of expert views on intergenerational welfare translate into economically optimal climate policy paths that are consistent with the 2 °C (or 1.5 °C) target

Addressing climate change with behavioral science:A global intervention tournament in 63 countries

Effectively reducing climate change requires marked, global behavior change. However, it is unclear which strategies are most likely to motivate people to change their climate beliefs and behaviors. Here, we tested 11 expert-crowdsourced interventions on four climate mitigation outcomes: beliefs, policy support, information sharing intention, and an effortful tree-planting behavioral task. Across 59,440 participants from 63 countries, the interventions' effectiveness was small, largely limited to nonclimate skeptics, and differed across outcomes: Beliefs were strengthened mostly by decreasing psychological distance (by 2.3%), policy support by writing a letter to a future-generation member (2.6%), information sharing by negative emotion induction (12.1%), and no intervention increased the more effortful behavior-several interventions even reduced tree planting. Last, the effects of each intervention differed depending on people's initial climate beliefs. These findings suggest that the impact of behavioral climate interventions varies across audiences and target behaviors.</p

Addressing climate change with behavioral science:A global intervention tournament in 63 countries

Effectively reducing climate change requires marked, global behavior change. However, it is unclear which strategies are most likely to motivate people to change their climate beliefs and behaviors. Here, we tested 11 expert-crowdsourced interventions on four climate mitigation outcomes: beliefs, policy support, information sharing intention, and an effortful tree-planting behavioral task. Across 59,440 participants from 63 countries, the interventions' effectiveness was small, largely limited to nonclimate skeptics, and differed across outcomes: Beliefs were strengthened mostly by decreasing psychological distance (by 2.3%), policy support by writing a letter to a future-generation member (2.6%), information sharing by negative emotion induction (12.1%), and no intervention increased the more effortful behavior-several interventions even reduced tree planting. Last, the effects of each intervention differed depending on people's initial climate beliefs. These findings suggest that the impact of behavioral climate interventions varies across audiences and target behaviors.</p

Addressing climate change with behavioral science: a global intervention tournament in 63 countries

Effectively reducing climate change requires marked, global behavior change. However, it is unclear which strategies are most likely to motivate people to change their climate beliefs and behaviors. Here, we tested 11 expert-crowdsourced interventions on four climate mitigation outcomes: beliefs, policy support, information sharing intention, and an effortful tree-planting behavioral task. Across 59,440 participants from 63 countries, the interventions’ effectiveness was small, largely limited to nonclimate skeptics, and differed across outcomes: Beliefs were strengthened mostly by decreasing psychological distance (by 2.3%), policy support by writing a letter to a future-generation member (2.6%), information sharing by negative emotion induction (12.1%), and no intervention increased the more effortful behavior—several interventions even reduced tree planting. Last, the effects of each intervention differed depending on people’s initial climate beliefs. These findings suggest that the impact of behavioral climate interventions varies across audiences and target behaviors