Authors from Princeton, Dartmouth and Exeter published this. The abstract:
“Though some warnings about online “echo chambers” have been hyperbolic, tendencies toward selective exposure to politically congenial content are likely to extend to misinformation and to be exacerbated by social media platforms. We test this prediction using data on the factually dubious articles known as “fake news.” Using unique data combining survey responses with individual-level web traffic histories, we estimate that approximately 1 in 4 Americans visited a fake news website from October 7-November 14, 2016. Trump supporters visited the most fake news websites, which were overwhelmingly pro-Trump. However, fake news consumption was heavily concentrated among a small group — almost 6 in 10 visits to fake news websites came from the 10% of people with the most conservative online information diets. We also find that Facebook was a key vector of exposure to fake news and that fact-checks of fake news almost never reached its consumers.”
So fake news bias is not at all the same as real news bias. Same for anti-science and science bias. False equivalency. The first paragraph below supports this in that only a certain sub-set (as described above) consume only fake news in their filter bubbles. Another study showed the rest of us fact-check and compare other news sources and hence are not as inclined to confirmation bias:
“The combination of rising partisanship and pervasive social media usage in the United States have created fears of widespread “echo chambers” and “filter bubbles” (Sunstein, 2001; Pariser, 2011). To date, these warnings appear to be overstated. Behavioral data indicates that only a subset of Americans have heavily skewed media consumption patterns” (Gentzkow and Shapiro, 2011; Barber´a et al., 2015; Flaxman, Goel, and Rao, 2016; Guess, 2016).