Public sentiment about various issues—whether they be social, political, or scientific—stands at the heart of any democratic system. Citizens express their opinions and convey their interests to decision makers, who ideally should consider such views when implementing policy. The news media, charged with informing citizens about the world around them, highlight events, issues, and concerns and often report public opinion about these concerns. For science-related issues as for many others, opinion polls are a news staple.

In their daily interactions, some citizens seek information and advice from others, while others attempt to persuade their friends and family to adopt particular views or vote for a specific candidate. Indeed, assessing public opinion on a particular issue and identifying the forces that shape such sentiment are critical in ...