Measuring the Burden of Alliance Activities

The classic public-goods model of an alliance introduced by Mancur Olson and Richard Zeckhauser in 1966 has been used to analyze issues associated with the allocation and distribution of goods produced by alliance members. One of the central results of their analysis is that rich nations are exploited by the poor because of a tendency for the poor to free-ride on the contributions of the rich. The sort of pure-public goods they described, however, link alliance members in such an intimate relationship that the use of the traditional measure of defense burden in an alliance context needs to be reexamined. This Note suggests a new measure of burden in the alliance context. This measure equals that part of a member's contribution that spills over to other members divided by the member's full income, which is defined as the sum of national income plus that part of other members' contributions that spill over to the nation in question. The author also discusses empirical estimates of the spillover parameters.