Adverse Selection and Inertia in Health Insurance Markets: When Nudging Hurts
研究大型企业保险变更中消费者的惯性行为，发现减少惯性的助推政策会加剧逆向选择，使福利损失翻倍。
This paper investigates consumer inertia in health insurance markets, where adverse selection is a potential concern. We leverage a major change to insurance provision that occurred at a large firm to identify substantial inertia, and develop and estimate a choice model that also quantifies risk preferences and ex ante health risk. We use these estimates to study the impact of policies that nudge consumers toward better decisions by reducing inertia. When aggregated, these improved individual-level choices substantially exacerbate adverse selection in our setting, leading to an overall reduction in welfare that doubles the existing welfare loss from adverse selection.