Aggregation and Dynamics of Survey Responses: The Case of Presidential Approval

Abstract

In this paper we critique much of the empirical literature on the important political science concept of presidential approval. Much of the recent research on presidential approval has focused on the dynamic nature of approval; arguments have raged about whether presidential approval is integrated, co-integrated, or fractionally integrated. We argue that none of these time-series concepts, imported from an econometrics literature which has fundamentally different types of data than do political scientists, can apply to the presidential approval time series. Instead, we advocate careful use of aggregated approval as a time-series cross-section, or the use of individual-level survey responses. Ultimately most of the important hypotheses political scientists wish to test regarding presidential approval involve individual voters or citizens; thus we argue that using the appropriate data unit is the best methodology.