Partisan Dynamics and the Volatility of Presidential Approval

In many areas of political science, scholars have begun to emphasize the dynamics driving the statistical variance of political outcomes as well as those governing changes in the mean. Some recent studies have brought this methodological focus on variance to measures of presidential approval, but no one has yet examined how the effects of traditional explanatory variables (such as major events and war) on the volatility of approval interact with respondents’ partisan predispositions. Using both aggregate approval data and individual-level panel data, this analysis demonstrates that factors reinforcing a group’s partisan proclivities to support or oppose the president increase the stability of that group’s support, while developments that conflict with a group’s partisan predispositions increase the volatility of approval.