保险人风险与公共风险分担: 再保险价值的量化
Insurer Risk and Public Risk-Sharing: Quantifying the Value of Reinsurance
Review of Economic Studies · 2026 · [{"name": "Paul H S Kim", "affiliation": ["Michigan State University"]}, {"name": "Anran Li", "affiliation": ["University of Minnesota", "Twin Cities Orthopedics"]}]
中文摘要
摘要 我们研究在企业面临巨大成本不确定性的市场中公共风险分担的作用, 重点关注健康保险中的公共再保险。我们构建了一个模型: 保险公司通过风险费用将成本不确定性内部化, 而风险费用会抬高有效边际成本, 从而为再保险创造了作用空间。公共再保险同时降低了预期成本与成本波动, 对规模较小的保险公司尤为明显, 进而降低价格并增强竞争。利用各州交错实施的州级再保险项目所做的事件研究, 我们发现公共再保险促使保险公司降低价格并减少私人再保险购买, 其中财务受限的保险公司受益最大。结构估计表明, 风险费用解释了保费—成本楔子中相当大的一部分, 并凸显了公共再保险相对于保费补贴的比较优势——即提供风险保护并增强竞争。我们的结果强调了在政策设计中考虑企业风险暴露的重要性, 并为理解公共风险分担政策提供了一个一般性框架。
Abstract
Abstract We study the role of public risk-sharing in markets where firms face substantial cost uncertainty, focusing on public reinsurance in health insurance. We develop a model where insurers internalize cost uncertainty through risk charges that raise effective marginal costs, and create a role for reinsurance. Public reinsurance lowers both expected costs and cost volatility, particularly for smaller insurers, reducing prices and enhancing competition. Using an event study of staggered state-level reinsurance programs, we show that public reinsurance leads insurers to lower prices and private reinsurance purchases, benefiting financially constrained insurers the most. Structural estimates indicate that risk charges account for a substantial share of the premium-cost wedge, and highlight public reinsurance's comparative advantage over premium subsidies by providing risk protection and enhancing competition. Our results underscore the importance of accounting for firms’ risk exposure in policy design and provide a general framework for understanding public risk-sharing policies.