Interdependency in vaccination policies among Japanese municipalities
研究发现日本市町村的疫苗接种补贴政策与邻近地区正相关，且这种模仿行为主要发生在同一县内，可能不利于优化社区健康，对地方自治提出质疑。
Economic theory predicts that vaccination policies at the local level can be negatively affected by the policies of neighboring regions because of free-riding motives, whereas positive dependency may exist due to policy diffusions among localities. By using the unique variations in the provision of vaccination subsidies in Japan, we assess how vaccination policies in a local government are affected by the decisions of neighboring governments. We find that the provision of vaccination subsidies is positively correlated with the decisions of neighboring localities. Moreover, a correlation is found with neighboring municipalities within the same prefecture but not with those in surrounding prefectures, indicating that the correlations are likely to arise because of mimicking behavior among localities within a prefecture. Our results show that vaccination policies tend to be formed following neighboring municipalities and do not necessarily aim to optimize community health, thus questioning the autonomy of local government authorities regarding vaccination policies.