Monday, December 19, 2005

The Media's Measurable Bias


The University of California touts "A Measure of Media Bias" (Quarterly Journal of Economics, Vol. 120, No. 4), by Tim Groseclose of UCLA and Jeffrey Milyo of the University of Missouri:
Abstract: 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, 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. Consistent with claims made by conservative critics, CBS Evening News and the New York Times received scores far to the left of center. The most centrist media outlets were PBS NewsHour, CNN’s Newsnight, and ABC’s Good Morning America; among print outlets, USAToday was closest to the center. All of our findings refer strictly to news content; that is, we exclude editorials, letters, and the like. . . .

Our results show a strong liberal bias. All of the news outlets except Fox News’ Special Report and the Washington Times received a score to the left of the average member of Congress. And a few outlets, including the New York Times and CBS Evening News, were closer to the average Democrat in Congress than the center. These findings refer strictly to the news stories of the outlets. That is, we omitted editorials, book reviews, and letters to the editor from our sample. . . .

To compute our measure, we count the times that a media outlet cites various think tanks and other policy groups. We compare this with the times that members of Congress cite the same think tanks in their speeches on the floor of the House and Senate. By comparing the citation patterns we can construct an ADA score for each media outlet. . . .

Over this period [1995-99] the mean score of the Senate (after including phantom D.C. senators and weighting by state population) varied between 49.28 and 50.87. The mean of these means was 49.94. The similar figure for the House was 50.18. After rounding, we use the midpoint of these numbers, 50.1, as our estimate of the adjusted ADA score of the centrist United States voter. . . .
I would consider an ADA score below 40 to be unbiased, that is, anchored in a correct understanding of how the world works and ought to work. I base that criterion on the ADA scores of legislators who cite think tanks. Consider, from Table I of the Groseclose-Milyo paper, the following average ADA scores for legislators who cite nonsectarian conservative-libertarian think tanks: American Conservative Union 32.0; American Enterprise Institute, 36.6; Americans for Tax Reform, 18.7; Cato Institute 36.3; Citizens Against Government Waste, 36.3; Heritage Foundation, 20.0; Hoover Institution, 36.5; Hudson Institute, 25.3; National Federation of American Businesses, 26.8; National Taxpayers Union, 34.3.

The following table highlights ADA scores for selected legislators and gives the average ADA scores for Democrats and Republicans (in boldface). The average scores indicate that Congress's polarization is as real as the media's leftward bias.
Average Adjusted ADA Scores of Legislators

Legislator - Average score
Maxine Waters (D-CA) - 99.6
Ted Kennedy (D-MA) - 88.8
John Kerry (D-MA) - 87.6
average Democrat - 84.3
Tom Daschle (D-SD) - 80.9
Joe Lieberman (D-CT) - 74.2
Constance Morella (R-MD) - 68.2
Ernest Hollings (D-SC) - 63.7
John Breaux (D-LA) - 59.5
Christopher Shays (R-CT) - 54.6
Arlen Specter (R-PA) - 51.3
James Leach (R-IA) - 50.3
Howell Heflin (D-AL) - 49.7
Tom Campbell (R-CA) - 48.6
Sam Nunn (D-GA) - 48.0
Dave McCurdy (D-OK) - 46.9
Olympia Snowe (R-ME) - 43.0
Susan Collins (R-ME) - 39.3
Charlie Stenholm (D-TX) - 36.1
Rick Lazio (R-NY) - 35.8
Tom Ridge (R-PA) - 26.7
Nathan Deal (D-GA) - 21.5
Joe Scarborough (R-FL) - 17.7
average Republican - 16.1
John McCain (R-AZ) - 12.7
Bill Frist (R-TN) - 10.3
Tom Delay (R-TX) - 4.7
Now for the bottom line. Recall that the following scores are based on news content -- not editorials, book reviews, or letters the editor -- thus the seemingly anomalous results for the Drudge Report and Wall Street Journal.
Rankings Based on Distance from Center

Rank - Media outlet - Estimated ADA score
1 - Newshour with Jim Lehrer - 55.8
2 - CNN NewsNight with Aaron Brown - 56.0
3 - ABC Good Morning America - 56.1
4 - Drudge Report - 60.4
5 - Fox News' Special Report with Brit Hume - 39.7
6 - ABC World News Tonight - 61.0
7 - NBC Nightly News - 61.6
8 - USA Today - 63.4
9 - NBC Today Show - 64.0
10 - Washington Times - 35.4
11 - Time Magazine - 65.4
12 - U.S. News and World Report - 65.8
13 - NPR Morning Edition - 66.3
14 - Newsweek - 66.3
15 - CBS Early Show - 66.6
16 - Washington Post - 66.6
17 - LA Times - 70.0
18 - CBS Evening News - 73.7
19 - New York Times - 73.7
20 - Wall Street Journal - 85.1
Only the Washington Times and Fox News, with ADA scores below 40, meet my criterion for objectivity. The rest are biased to the left by varying degrees, but none of them comes close to objectivity. That is not news, of course. As Groseclose and Milyo note,
[s]urvey research has shown that an almost overwhelming fraction of journalists are liberal. For instance, Elaine Povich [1996] reports that only seven percent of all Washington correspondents voted for George H.W. Bush in 1992, compared to 37 percent of the American public. Lichter, Rothman and Lichter, [1986] and Weaver and Wilhoit [1996] report similar findings for earlier elections. More recently, the New York Times reported that only eight percent of Washington correspondents thought George W. Bush would be a better president than John Kerry. This compares to 51 percent of all American voters. David Brooks notes that for every journalist who contributed to George W. Bush’s campaign, another 93 contributed to Kerry’s campaign.
And it shows up in their reportage. So much for "objective journalism."