On the Economic Effects of Multiple Unionism
基于英国企业数据，发现多重工会且分别谈判的工厂工资更高，并用工人可替代性理论解释这一现象。
In a recent paper, Stephen Machin, Mark B. Stewart, and John Van Reenan (1993), using establishment-level data for the United Kingdom, find that, ceteris paribus, plants with multiunionism and separate bargaining arrangements pay higher wages than either those in which different unions bargain jointly or those in which there is a single union. In this paper, the author offers a theoretical interpretation of this result within the framework of the Henrik Horn and Asher Wolinsky (1988) analysis of worker substitutability and patterns of unionization. Copyright 1995 by The editors of the Scandinavian Journal of Economics.