Talamàs Eduard, Vohra Rakesh
IESE Business School, Spain.
University of Pennsylvania, United States of America.
Games Econ Behav. 2020 Jul;122:277-289. doi: 10.1016/j.geb.2020.05.001. Epub 2020 May 8.
Risk compensation can undermine the ability of vaccines to curb epidemics: Vaccinated agents may optimally choose to engage in more risky interactions and, as a result, may increase everyone's infection probability. We show that-in contrast to the prediction of standard models-things can be worse than that: Free and perfectly safe but only partially effective vaccines can , and hence fail to satisfy-in a strong sense-the fundamental principle of "first, do no harm." Our main departure from standard economic epidemiological models is that we allow agents to strategically choose their partners, which we show creates strategic complementarities in risky interactions. As a result, the introduction of a partially-effective vaccine can lead to a much denser interaction structure-whose negative welfare effects overwhelm the beneficial direct welfare effects of this intervention.
接种疫苗的个体可能会最优地选择参与更具风险的互动，结果可能会增加每个人的感染概率。我们表明，与标准模型的预测相反，情况可能比这更糟：免费且完全安全但仅部分有效的疫苗可能会，因此在强烈意义上无法满足“首先，不造成伤害”的基本原则。我们与标准经济流行病学模型的主要不同之处在于，我们允许个体策略性地选择他们的伙伴，我们表明这会在风险互动中产生策略互补性。因此，引入一种部分有效的疫苗可能会导致互动结构更加密集，其负面福利效应超过了这种干预的有益直接福利效应。
