How effective is nudging? A quantitative review on the effect sizes and limits of empirical nudging studies

摘要

Changes in the choice architecture, so-called nudges, have been employed in a variety of contexts to alter people's behavior. Although nudging has gained a widespread popularity, the effect sizes of its influences vary considerably across studies. In addition, nudges have proven to be ineffective or even backfire in selected studies which raises the question whether, and under which conditions, nudges are effective. Therefore, we conduct a quantitative review on nudging with 100 primary publications including 317 effect sizes from different research areas. We derive four key results. (1) A morphological box on nudging based on eight dimensions, (2) an assessment of the effectiveness of different nudging interventions, (3) a categorization of the relative importance of the application context and the nudge category, and (4) a comparison of nudging and digital nudging. Thereby, we shed light on the (in)effectiveness of nudging and we show how the findings of the past can be used for future research. Practitioners, especially government officials, can use the results to review and adjust their policy making.