記述的規範の落とし穴―防災行動を促進するためのナッジが逆効果になる場合―

抄録

A nudge by descriptive norms is one of the most effective interventions to promote disaster preparedness. However, it can have negative consequences that unintendedly repress the desired mitigation, especially in Japan. We hypothesized that the pitfall emerges within the boundary conditions of the attitudes towards preparedness. Descriptive norms inform people about preparedness behaviors; a certain number of people do not prepare and this can be a cause of the side effect of descriptive norms among people holding negative attitudes towards disaster preparedness. We examined the negative effects of descriptive norms on disaster preparedness behaviors, which are drawn from a wide variety of preparedness behaviors with various levels of descriptive norms. A pre-registered experiment confirmed the superiority of the interaction effect model over the model without interaction; descriptive norms backfired among people with negative attitudes. The practical and theoretical implications were also discussed.