Crowding in with impure altruism: Theory and evidence from volunteerism in national parks
Journal of Public Economics · 2023 · Matthew J. Kotchen、Katherine R. H. Wagner
中文摘要
本文对私人提供公共品的文献作出三点贡献。第一，我们指出了一种常用规范检验的局限性；该检验依据挤出程度来区分纯利他主义和不纯利他主义的标准模型。现有文献将“不纯利他主义下的挤出效应应小于纯利他主义下的挤出效应”这一结果视为既定结论，而我们表明，前者既可能大于也可能小于后者。第二，我们提出一种新的、更一般化的检验，其依据是是否存在挤入效应，或存在超过一比一的挤出效应，因为这两种情形都仅与不纯利他主义相一致。第三，我们提供了经验证据。利用一套独特的美国国家公园志愿服务面板数据，我们估计了公园公共资金变化对园内志愿服务规模的因果效应。总体发现是，公共支出每增加1美元，平均会挤入价值27美分的志愿服务。我们说明，挤入效应的估计结果，以及基于公园类型和志愿服务时数类型的异质性，在理论上如何与主流的不纯利他主义模型相一致。
Abstract
This paper makes three contributions to the literature on private provision of public goods. First, we identify limitations of the frequently used specification test that distinguishes between the standard models of pure and impure altruism based on the extent of crowding out. While the literature takes as given the result that crowding out should be less with impure altruism than with pure altruism, we show that it can be either more or less. Second, we propose a new, more general test based on the presence of crowding in or greater than one-for-one crowding out, both of which are consistent with impure altruism only. Third, we provide empirical evidence. Using a unique panel data set on volunteerism in U.S. National Parks, we estimate the causal effect of changes in a park’s public funding on the amount of within-park volunteerism. The overall finding is that each additional dollar of public expenditure crowds in 27 cents worth of volunteerism on average. We show how the estimates of crowding in, along with heterogeneity based on park and volunteer hour types, are theoretically consistent with the mainstay model of impure altruism.