What Matters, Information or Awareness? The Key to the Mystery of Mass Media Effects.

Abstract

This dissertation examines the moderating impact of information on mass media effects. It argues that, building upon the concept of information, the theory in this dissertation provides a unifying model for previous research about when the mass media have stronger effects on the attitudes and opinions of the audience (e.g. Zucker, 1978, Mutz, 1998, and Gamson, 1992). It also argues that information can explain and predict the magnitude of communication effects in addition to the concept of political awareness as proposed by Zaller (1992).

Information as used in this dissertation refers to what an individual knows about a particular object, which could be a political issue or candidate, a policy, or a commercial product that is discussed in a media message. Information differs from political awareness as measured by general political knowledge due to its specificity, which is exactly why it can contribute to our theoretical and empirical understanding of the complexity of attitudes and opinions.

Three experiments are conducted to test the theory proposed in this dissertation that the magnitude of effects resulted from exposure to media messages tends to decrease as the level of information increases. In other words those who have more information about a particular issue are less likely to be influenced by mass media messages than those who have less information.

The empirical testing finds some support for the theory proposed in this dissertation about the moderating impact of specific information on news media effects. Even though there are mixed results with regard to the direction, magnitude and how wide spread such effects are, the evidence demonstrated in this study surely supports the argument that specific issue information is a construct that should not be dismissed easily.