Behavioral climate interventions are often promoted as politically feasible substitutes for carbon taxes, yet we lack a way to value them in tax-equivalent terms. I develop and field-test a framework that benchmarks such interventions against a carbon tax. In a German student canteen, a framed field (N = 289) and a natural field experiment (125,000 purchases) show that carbon labels replicate the effect of a €120/t carbon tax. A third experiment (N = 444) and a structural model show that the effect is driven mainly by increased salience rather than misperception correction, and that the labels raise consumer welfare.

We compare the behavior and welfare effects of two popular interventions for resource conservation. The first intervention is social comparison reports (SC), which primarily provides consumers with information motivating behavioral change. The second intervention is real-time feedback (RTF), which primarily provides consumers with information facilitating behavioral change. In a field experiment with around 1,000 participants, we directly observe the interventions’ effects on participants’ behavior. Further, we elicit participants’ willingness to pay for receiving the interventions, both before and after having experienced them for one month. We find that SC leads to a reduction in water use per shower by 9.4%, RTF by 28.8%, and the combination (BOTH) by 35.0%. Our willingness to pay results show that all interventions are highly valued by participants and that willingness to pay for RTF and BOTH is significantly higher than for SC. Furthermore, we find that the valuation of the interventions barely changes after a one-month experience. Our results suggest that while both interventions improve welfare, providing consumers with information facilitating behavioral change achieves a higher impact and a slightly higher welfare increase than providing consumers with information motivating behavioral change.

Press release: RWI

Media: FAZ | Energy Institute at Haas

In a laboratory experiment, we study the effect of acute and chronic stress on individual risk-taking behavior. We exogenously induce acute stress using the Trier Social Stress Test for Groups developed by von Dawans, Kirschbaum, and Heinrichs (2011). We measure subjects' acute stress by their heart rate, saliva cortisol levels, and their chronic stress by their hair cortisol levels. We elicit the subjects' risk-taking tendency by using randomized lottery pairs. Employing a within-subject design, i.e., eliciting each subject's risk-taking propensity both with and without the exogeneous acute stress, we aim to shed light on individuals' heterogeneous responses to acute stress in terms of risk-taking. It thereby contributes to the inconclusive literature on the causal effect of acute stress on risk-taking.

Interventions to decrease meat consumption are often only implemented for short periods of time, and it is unclear how they might have lasting effects. We combine student canteen consumption (over 270,000 purchases made by over 4,500 guests) and survey data (N>800) to study how a one-month intervention to decrease meat consumption affects consumer behavior post-intervention. During the intervention period, meat meals were eliminated from the menu of the treatment canteen, while the two control canteens were unaffected. Using a difference-in-difference approach, we estimate that guests usually frequenting the treatment canteen did not significantly reduce their visits to the canteen during or after the intervention. In the two months following the intervention, they were still 4% less likely to choose the meat option when visiting the canteen, relative to baseline. A large part of this effect seems explicable with guests learning about the quality of the canteen’s vegetarian meals. We find little to no evidence of the intervention changing perceived social norms.

Press release: English | German

Media: SRF 4 | Deutschlandfunk Nova | WDR Cosmo | Rhein-Zeitung | General-Anzeiger Bonn | Bild der Wissenschaft | Aponet | Yumda

We study how social interactions shape meal choices using detailed canteen transaction data comprising roughly two million purchases over one academic year. Leveraging purchase timestamps, we infer social dining networks among university students and examine how exposure to vegetarian peers influences individual consumption patterns. Our data allows to distinguish between general trends in meal choices and socially-driven changes in meat consumption. We find that individuals who dine more frequently with vegetarian peers over the course of the year tend to increase their own vegetarian meal consumption. We then provide causal evidence that dining with a vegetarian peer on a given day reduces meat consumption by about 3 percentage points, corresponding to approximately 7% of baseline levels. Survey responses and supplementary analyses allow us to hone in on the channels driving these effects. Together, our findings highlight how social contexts can shape sustainable consumption behaviors.