Transparency and accountability are important conditions for a well-functioning political system. Does a strong and independent media industry help promote transparency and accountability? Our faculty lead investigations on whether and how media presence and the political system affect each other.

Does Media Concentration Lead to Biased Coverage? Evidence from Movie Ratings.

By Stefano DellaVigna of Berkeley-Haas and Johannes Hermle of the University of Bonn, Oct. 2014. To examine whether increased media concentration produces a bias in favor of the parent company’s holdings, the researchers examined movie reviews from media outlets owned by two entertainment conglomerates — News Corp. and Time Warner. The study found no evidence of bias, including bias by omission.

Fox News’s substantial impact on voting.

This pioneering study, co-authored by Stefano Della Vigna, examined election data in 9,526 towns that began receiving Fox News between 1996 and 2000. It found that the arrival of Fox in local media markets increased the Republican vote share by as much as .7 percentage points between the 1996 and 2000 elections. Overall, it estimated, Fox had persuaded between 3 and 28 percent of its viewers to vote Republican.

The Impact of cross-border spillover from Serbian radio programming on ethnic hatred in Croatia.

This 2013 study, co-authored by Stefano DellaVigna, examined areas in Croatia that received Serbian radio signals, which many Croatians tuned in to hear non-political programming. The researchers found that Serbian radio, intended for audiences inside Serbia, sparked a surge in hostility toward Croatian Serbs that was significantly higher than the increases in areas outside Serbian radio range.