Measuring Belief Certainty in Political Knowledge

Political knowledge measures what people know and how they reason about politics, but scholars still debate how to best measure the concept. A growing body of survey research has demonstrated the theoretical importance of measuring an individual’s expressed belief certainty about their own informedness. Yet existing political knowledge measures typically fail to recover this information. This article validates a question format that allows respondents to express their level of certainty in their knowledge about politics and government. The analyses show that the certainty-in-knowledge format: (1) reduces systematic differences between men and women in responding “Don’t Know,” and (2) decreases answer look-up on online surveys. Validity, reliability, and information analyses further demonstrate that incorporating belief certainty results in a knowledge scale that displays theoretically expected relationships with a range of outcome variables while also having superior psychometric properties. Additionally, the certainty-in-knowledge format eliminates the confounding influence of response option cues and can be applied to questions on any topic—political figures, institutional rules, policies, and surveillance facts. This shift in measurement can be made without costly changes to survey questionnaire design and length. Finally, the new format represents a more realistic conception of citizen competence: one that elevates the ability of discerning true from false political information.