a1 Universiteit Leiden
a2 University of North Carolina at Chapel Hill
a3 University of North Carolina at Chapel Hill
Two theories are now used to explain the size and composition of interest communities: Olson's (1965, 1982) bottom-up collective action model and Gray and Lowery's top-down ESA model. Unfortunately, one of the common ways of testing these models—aggregate-level analyses of interest populations—cannot easily distinguish between them. Empirical evidence supporting one model will almost inevitably support the other. We explain why this is so, illustrating the problem with data on state populations of health interest organizations. We also discuss how the two models might be better distinguished.
(Received March 26 2007)
(Accepted December 26 2007)
David Lowery is professor in departement bestuurkunde, Universiteit Leiden, 2300 RB Leiden, Nederland.
Virginia Gray and Robert Watson Winston are distinguished professor of political science, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599.
James Monogan is Ph.D. candidate in political science, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599.