Rotten Kids, Purity, and Perfection
证明，在不存在可转移效用的情况下，若外部性表现为单一纯公共品，贝克尔提出的“坏孩子定理”依然成立。
Bergstrom has shown that becker's “Rotten Kid theorem” holds in a world of two commodities if their utilities are transferable. The present paper identifies a further circumstance in which the theorem is valid. We show that it also holds in the absence of transferable utility if the externalities are assumed to take the form of a single pure public good.