On the conservative side, the strongest case might have been made by Tim Groseclose, a political science and economics professor at the University of California at Los Angeles. Groseclose used a three-pronged test to quantify the “slant quotient” of news stories reported by dozens of media sources. He compared these ratings with a statistical analysis of the voting records of various national politicians. In his 2011 book, “Left Turn: How Liberal Bias Distorts the American Mind,” Groseclose concluded that most media organizations aligned with the views of liberal politicians. (Groseclose determined that The Washington Post’s “slant quotient” was less liberal than news coverage in the New York Times and Wall Street Journal.)
Even with conservative-leaning sources such as the Drudge Report and the Washington Times factored in, “the aggregate slant is leftward,” said Groseclose, who describes himself as a conservative.
But that’s not the end of the story. A “meta-analysis” of bias studies — that is, a study of studies — shows something different: When all is said and done, left-leaning reporting is balanced by reporting more favorable to conservatives. “The net effect is zero,” said David D’Alessio, a communications sciences professor at the University of Connecticut at Stamford.
D’Alessio drew his conclusion from reviewing 99 studies of campaign news coverage undertaken over six decades for his newly published work, “Media Bias in Presidential Election Coverage 1948-2008: Evaluation via Formal Measurement.” The research, he says, shows that news reporting tends to point toward the middle, “because that’s where the people are, and that’s where the [advertising] money is. . . . There’s nuance there, but when you add it all and subtract it down, you end up with nothing.”
So why the rise in the public’s perception of media bias? A few possibilities:
l The media landscape has changed.
There’s more media and more overtly partisan media outlets, too. The Internet has given rise to champions of the left — Huffington Post, Daily Kos, etc. — as well as more conservative organizations such as Drudge and Free Republic. This means your chance of running into “news” that seems biased has increased exponentially, elevating the impression that “bias” is pervasive throughout all parts of the media.