It is widely recognized that interest groups affect both microeconomic and macroeconomic outcomes. However, few researchers have attempted to discern empirically the factors that contribute to interest group activity. This paper provides a test of several theories of group formation in a panel...

This paper provides evidence that interest group activity is negatively related to aggregate stock market performance. In particular, the ¯ndings imply that a one percent increase in the number of interest groups in a country is associated with a reduction in average annual stock market returns...

This paper explores the relationship between special-interest groups and economic growth, using newly assembled data on the number of groups observed across countries. In a sample of 86 countries at two points in time (for a total of 169 observations), we ¯nd support for Mancur Olson's theory...

This paper empirically explores the relationship between special-interest groups and volatility, with focus on the interplay between groups and democracy and on the impact of groups on policy volatility. We find that countries with more interest groups are characterized by less policy...

This paper explores the relationship between special-interest groups and volatility of GDP growth. In an unbalanced panel of 108 countries, we find a significant negative relationship between the number of interest groups in a country and the volatility of GDP growth.