THE DIVERSITY OF STATE INTEREST GROUP SYSTEMS

As part of a larger effort to develop an independent system-level theo ry of interest groups, we explore the system-level trait of interest g roup diversity. A model of state interest group-diversity is developed and tested with state data from the early 1980s. We find that interes t group diversity is related to economic diversity and economic size, whereas its relation to wealth and to the number of interest groups co ntrasts sharply with much of our conventional wisdom about state inter est groups. We discuss the implications of these findings for understa nding state interest group politics and outline how they contribute to a larger research program on state interest group systems.