PNAS Nexus: Nudges for Climate? Data are more likely to favor a Zero effect than any effect at all
There is evidence for small between-study heterogeneity, indicating that some specific interventions might have an effect. These results suggest that, on average, behavioral interventions without incentives on households and individuals are unlikely to deliver material climate benefits.
Although behavioral interventions targeting citizens are frequently advocated as a cost-effective means of encouraging eco-friendly behavior, the effectiveness estimates found in published studies vary widely. A team of researchers amon them being INCHER members Adam Hardaker, Igor Asanov, and Stephan Bruns conducted a reanalysis of the evidence regarding non-incentivized behavioral interventions on citizens. They found that when publication bias and model uncertainty are taken into consideration with multilevel RoBMA (Robust Bayesian Meta-Analysis), the data provide strong support for a zero average effect.
Adam Hardaker, Igor Asanov, František Bartoš, Stephan B Bruns (2026) No evidence that non-incentivized behavioral interventions effectively mitigate climate change after adjusting for publication bias PNAS Nexus, pgag150, https://doi.org/10.1093/pnasnexus/pgag150Open Access.