Stability and Change: The Time Varying Impact of Economic and Foreign Policy Evaluations on Presidential Approval

Most researchers studying presidential approval with time series analysis assume that foreign and economic policy have a time-invariant weight in citizens' judgments of presidential performance. However, those studying presidential approval in cross-sectional analysis find that the weight of foreign and economic policy on job performance fluctuates as news about these issues changes. These competing views can be incorporated into a model of rational learning that makes it possible to test whether the public weighs foreign and economic policy differently over time in its evaluation of the president. The analysis presented here shows that foreign and economic policy exhibit different patterns in their relationship to overall approval-economic policy has a consistent impact over time, while foreign policy ebbs and flows. Do citizens use the same criteria for evaluating presidents over time? Given historical changes in the economy (like the stagflation of the 1970s, the high interest rates and high deficits of the 1980s, and nearly a decade of economic growth coupled with low inflation and low unemployment in the 1990s), and the emergence and disappearance of foreign policy issues (like the Vietnam War, the Cold War, the Gulf War, and the recent war on terrorism), the most surprising answer to this question might be "yes." Yet, for the most part, those who research presidential approval over time would in fact agree with this positive answer. Time series analysts of presidential approval generally make the assumption that citizens reward or punish the president the same way today as they did in the 1960s. But for researchers who study the information environment in which citizens make judgments about the president, the answer to the opening question is "no." They reach this conclusion because they believe that the shifting political context in which citizens find themselves embedded leads to changes in the criteria they use to evaluate presidents. For example, in the priming literature, Krosnick and Kinder (1990: 510) argue that, "shifts in news media content alter the political importance that the public attaches to the flow of events. . . . [T]hrough its monopoly over the immediate telling of political history, media possess the power to influence what the public considers and what it ignores."1 The key differences in these two views-one that sees the public using consistent criteria to evaluate the president and one that sees the criteria as shifting-are rooted in assumptions about the public's need or ability to learn and adapt based on new information. If the public has a well-developed framework for how presidents should be rewarded or punished for their performance, then the criteria that citizens use should be relatively similar across time. In this case, new information will change the reward or punishment that the president receives but not the weight that is attached to this information. If on the other hand the public is uncertain about how to evaluate the president, then it is likely that people would change the criteria that they use to evaluate the president as new information is reported to them. In order to study these two competing views of the stability of the criteria the public uses to evaluate the president, it is necessary to build a model that does not assume stability or change, but allows for either possibility.2 This idea of the public learning (or not) as new information comes its way can be examined with the model of "rational learning" proposed here. It is similar to the "rational learning" approach used by Gerber and Green (1998) and is derived from "bounded rationality" models in economics (Sargent 1993; Cuthbertson, Hall, and Taylor 1992, chap. 7).3 The fundamental assumption of this model of learning is that the citizens do not have the time or desire to acquire all possible information about issues, but they use the information they receive from the media and other sources to make rational judgments about politics. …