Insurance can be classified into two broad categories: Compulsory (government/public) and Voluntary (market/private). In practice, the vast majority of compulsory insurance is partially compulsory, where compulsory insurance provides only partial coverage, and it allows for supplemental voluntary purchases (mixed insurance). In this paper, we use the Balloon Analogue Risk Task (BART) as both the assessment of risk-taking and insurance context to conduct an online experiment. The main objective is to compare purely compulsory, voluntary and mixed insurance in terms of adverse selection, moral hazard and social welfare simultaneously. We find adverse selection in purely voluntary insurance, but not in mixed insurance. Moral hazard exists in all three types of insurance, but it is smaller in mixed insurance. Finally, our results suggest that the combined effects of significant moral hazard and “no adverse selection” in purely compulsory insurance make it the insurance type with the lowest social welfare. Overall there is no crowd-out effect of the compulsory part on residual voluntary purchases in mixed insurance.

中文翻译：

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强制保险与自愿保险：在线实验

保险可分为两大类：强制性（政府/公共）和自愿性（市场/私人）。在实践中，绝大多数强制保险是部分强制保险，强制保险仅提供部分保障，并允许补充自愿购买（混合保险）。在本文中，我们使用气球模拟风险任务 (BART) 作为风险承担和保险上下文的评估来进行在线实验。主要目的是在逆向选择、道德风险和社会福利方面同时比较纯强制、自愿和混合保险。我们在纯自愿保险中发现逆向选择，但在混合保险中没有。道德风险在三种保险中都存在，但在混合保险中较小。最后，我们的研究结果表明，在纯强制保险中，显着的道德风险和“无逆向选择”的综合效应使其成为社会福利最低的保险类型。综合来看，强制部分对混合保险剩余自愿购买不存在挤出效应。