In a recent study, UCLA researchers Groseclose and Milyo claim that there is a liberal bias in media outlets. They devise an interesting method to calculate the political bias of news sources. The following is from their paper published in the November issue of the Quarterly Journal of Economics*:
We measure media bias by estimating ideological scores for several major media outlets. To compute this, we count the times that a particular media outlet cites various think tanks and policy groups, and then compare this with the times that members of Congress cite the same groups. Our results show a strong liberal bias: all of the news outlets we examine, except Fox News’ Special Report and the Washington Times, received scores to the left of the average member of Congress.
Using the above described methodology the researchers find the score of the average Senator to be 50.1, where 100 is most liberal. With this same scoring system, 4 0f the top 5 most liberal news sources are the usual suspects: The New York Times, CBS Evening News, The Los Angeles Times, and The Washington Post. One relatively surprising finding is that of the 20 major news outlets they studied, the Wall Street Journal is the most liberal with a score of 85.1.**
The most obvious criticism of their finding a liberal bias using this methodology (albeit probably not the strongest) is that perhaps news outlets cite liberal think tanks more often because they produce more relevant, and/or useful research. This might explain why the respected journalists at the WSJ have such a "liberal" bias.
* If you would like a copy of the 47 page paper, please email me. I can't publish it on the blog due to copyright issues.
** It must be noted that it is apparently a well-known fact in many circles that the news and the OPED departments at the WSJ are polar opposites.