地方公共品作为双刃剑：熟悉的正面溢出效应与对相对供给的区域性关切

摘要

This paper argues that an individual region’s local public goods (LPGs) function as a double-edged sword for other regions: while they generate familiar positive spillovers, they simultaneously provoke regional concern over relative provision. Armed with this novel insight, we revisit the classical public-finance problem of LPG provision. We demonstrate that once LPGs are modeled as a double-edged sword, the direction of bias under decentralized versus centralized provision — whether undersupply or oversupply — is theoretically ambiguous. Crucially, this indeterminacy persists irrespective of whether the social planner accounts for regional concern over relative LPG provision. Beyond its theoretical implications, our framework provides a natural economic rationale for prominent real-world phenomena, specifically the widespread emergence and proliferation of gated communities.