This multi-year study published in Science, in which 48 small media outlets were recruited to write articles on specific subjects on randomly assigned dates, finds that “exposure to the news media causes Americans to take public stands on specific issues, join national policy conversations, and express themselves publicly—all key components of democratic politics—more often than they would otherwise.”

After recruiting 48 mostly small media outlets, the researchers chose groups of these outlets to write and publish articles on approved subjects, on randomly assigned dates. They estimated the causal effect on proximal measures, such as website pageviews and Twitter discussion of the articles’ specific subjects, and distal ones, such as national Twitter conversation in broad policy areas. The intervention increased discussion in each broad policy area by ~62.7% (relative to a day’s volume), accounting for 13,166 additional posts over the treatment week, with similar effects across population subgroups.

Read the full report about news media activating agendas at Science magazine.