Abstract
Conspiracy theories, rumor and misinformation have a long history in the United States, but in recent years there has been a sharp increase in the prevalence of baseless beliefs, which we define as ideas held to be true by certain individuals but wholly lacking in evidence. Ideology plays a key role in many baseless beliefs, with most studies finding conservatives more likely to hold them than liberals. This paper explores the incidence of baseless beliefs using a national survey of 445 US adults. The study utilizes a susceptibility-exposure model, which holds that baseless beliefs are a function of individual traits and dispositions that make certain individuals susceptible when exposed to information about particular baseless claims. Results revealed three domains of baseless belief that are related to specific groupings of individual traits and media use. Some factors, like institutional distrust, predict baseless beliefs across all domains while some, like conservatism, predict baseless beliefs in only some of those categories. Similarly, we find patterns of media usage may play a role in explaining why only some individuals susceptible to holding certain types of baseless belief hold them. We conclude that baseless beliefs are not monolithic, and researchers should be careful in drawing generalized conclusions about their development and persistence.