What do we learn from public good games about voluntary climate action? Evidence from an artefactual field experiment

Evidence from public good game experiments holds the promise of instructive and cost-effective insights to inform environmental policy-making, for example on climate change mitigation. To fulfill the promise, such evidence needs to demonstrate generalizability to the specific policy context. This paper examines whether and under which conditions such evidence generalizes to voluntary mitigation decisions. We observe each participant in two different decision tasks: a real giving task in which contributions are used to directly reduce CO2 emissions and a public good game. Through two treatment variations, we explore two potential shifters of generalizability in a within-subjects design: the structural resemblance of contribution incentives between the tasks and the role of the subject pool, students and non-students. Our findings suggest that cooperation in public good games is linked to voluntary mitigation behavior, albeit not in a uniform way. For a standard set of parameters, behavior in both tasks is uncorrelated. Greater structural resemblance of the public goods game leads to sizable correlations, especially for student subjects.