Quantifying Media Bias

It is often said, mostly by conservatives, that the main stream media is biased in a liberal direction. Over the years, some studies confirming bias have drifted in: Slate magazine, for instance, polled its writers and discovered – big surprise! – that about 90 percent of the lads and ladies identified themselves as liberal. A similar poll among the writers at, say, National Review likely would show a like degree of bias in a conservative direction. But these are not hard news sites.

Some time ago, a more “scientific” study was done in connection with major news outlets, and again – big surprise! – the pollsters discovered that a preponderance of mainstream news writers were liberal. The authors of that study may or may not have been surprised to discover the Wall Street Journal’s news pages -- not its commentary pages, which are widely recognized as conservative – rate, according to a study done by Tim Groseclose, as the most liberal in the nation.

Until Mr. Groseclose, then a professor of political science and economics at UCLA and Jeffrey Milyo, then a public policy professor at the University of Chicago and now holder of an endowed chair in social sciences at the University of Missouri, first published in 2005 a scientific study of media bias in the Quarterly Journal of Economics, a Harvard University publication widely regarded in academia as one of the four top scholarly economic journals on in the country, there was no reliable scientific methodology to quantify bias in news outlets.

Having first produced a method that allowed a rigorous quantitative analysis, the two discovered that most major American news outlets, which included newspapers such as the Washington Post and the New York Times, newsweeklies such as Time and Newsweek, newsweekly television shows such as CBS Evening News and NBC Nightly News, and Internet sites such as – big surprise! -- the Drudge Report contained a sharp liberal bias.

After assigning an ADA-based number to the members of the House and Senate, Groseclose and Milyo then examined the frequency with which individual members of Congress, in bolstering their floor and committee arguments, cited the research of various think tanks and advocacy groups around Washington and elsewhere—organizations such as the Heritage Foundation and the Brookings Institution. By combining the frequency numbers with the PQs of the members of Congress, Groseclose and Milyo were able to assign PQs to the top 50 cited think tanks themselves—a far more objective way, in their thinking, to assign an ideological perspective to a think tank than simply to assume, for example, that the Heritage Foundation is conservative and the Sierra Club is liberal.

In a third step, Groseclose and Milyo quantified the frequency with which stories by reporters for various news outlets cited research and quoted spokesmen from those same think tanks as they fleshed out the facts that they reported. That enabled the two to calculate the outlets’ slant quotient, or SQ. As Groseclose and Milyo pointed out (and as Groseclose reiterates in Left Turn), the news stories themselves were seldom false or inaccurate. There was almost never anything intentionally dishonest about the reporting. It was just that the reporters presented their stories in a way that reflected, probably unconsciously, the reporters’ liberal ideological leanings. They used material from liberal think tanks and advocacy groups far more frequently than material from the tanks’ conservative opposite numbers. They highlighted or omitted facts as their personal political predilections dictated, even though their stories, in an effort to maintain journalistic impartiality, might contain a quotation or two from spokesmen for the conservative side.

In a review of Mr. Groseclose’s new book, “Left Turn,” Charlot Adams reports in the Weekly Standard:

“The range of SQs that Groseclose and Milyo calculated was shocking. The most liberally biased news outlet proved to be the Wall Street Journal (its news pages, that is, not its conservative editorial and opinion pages). The WSJ turned out to have the slant quotient of the average Democrat, about 85, only a few points below the 89.2 PQ of the late Ted Kennedy. Of the rest of the mainstream media, only Fox News (with an SQ of about 42) and the Washington Times (with an SQ of about 40) registered below the midpoint—and both outlets are way more liberal in their reporting than the average Republican, whose PQ is less than 20. The Drudge Report, although regarded as troglodytic by progressives, has an SQ of around 50—that is, its reporting is about as centrist as the average American voter these days.”

Matt Drudge, centrist – who woulda thunk it?