Cable News Coverage and Online News Stories: A Large Scale Comparison of Media Bias

We assess media bias in cable news reporting compared to online news stories. We make use of large-scale data resources to operationalize media bias on three levels: gatekeeping or news selection; coverage or differential attention to news; and the degree of subjectivity in news statements. We analyze the captions of about 140 cable channels in the US and hundreds of online news stories for six months, an observation window that coincides with the 2012 Republican primaries. Our findings suggest that cable channels are more similar to each other than to online news sources, but that similarities vary across the three levels of bias. The comparison between online news and cable channels also suggests that some of the differences are not related to systematic bias but to the amount of diversity that the two media allow (cable being more restricted by space constraints than online media).