Group Size Effects in Public Goods Provision: The Voluntary Contributions Mechanism
通过实验检验群体规模变化对公共品自愿供给中搭便车行为的影响，发现规模增大伴随边际回报下降时会降低配置效率，但单纯人数增加无此效应。
This paper examines the relationship between variations in group size and "free-riding" behavior in the voluntary provision of public goods. We examine experimentally two pertinent concepts: the marginal return to an individual from contributions to the public good, and the actual number of members in the group. Our results strongly support a hypothesis that increasing group size leads to a reduction in allocative efficiency when accompanied by a decrease in marginal return from the public good (as from crowding or an association of large groups with imperceptibility of marginal benefits). Our results do not support a pure numbers-in-the-group effect.