The effect of popular exemplars and expert account base-rate information on perceived public opinion

How people perceive public opinion is important because it affects their willingness to express themselves. This paper investigates whether two different portrayals of public opinion in the TV news affect people’s perception of public opinion. We use an experimental design in which roughly one thousand subjects were exposed to a fictional television news item. The news items contained either popular exemplars or base-rate information offered by experts each presenting different public opinion distributions. We find that exemplification, which is frequently employed in the news, has an effect on the news broadcast viewers’ perception of dominant public opinion. However, in contrast to previous work, we find that base-rate information has a larger effect on perceived public opinion when offered by a speaking source (expert) making it vivid. The factors underlying this differential effect are the success at being an attention commander and a credible source (trustworthiness and expertise). Speaking experts are evaluated as equally trustworthy and effective attention commanders as popular exemplars but have far greater expertise.