The Missing Main Effect of Welfare State Regimes: A Comment

Abstract

This article discusses Nate Breznau’s critique of Brooks and Manza’s "Social Policy Responsiveness in Developed Democracies." Brooks and Manza found that public opinion influenced welfare state spending, but Breznau argued that this conclusion was an artifact of their model, which included an interaction between opinion and welfare state type but omitted the main effect of welfare state type. Breznau is correct in saying that interactions should not be used without including the main effect, except in rare circumstances which do not apply in this case. However, the classification of welfare state type is made partly on the basis of the dependent variable, welfare spending, so it should not be used as an independent variable. There is, however, a case for including a variable for the type of legal system (common law or civil law), which is correlated with welfare state type. The estimates from a regression including both main and interaction effects support Brooks’s and Manza’s original conclusions about the effect of public opinion. The paper concludes by discussing the strength of the evidence provided by the data.

Keywords

• Interaction Effects
• Policy Responsiveness
• Replication
• Welfare State