The mass media serve as THE major alerting mechanisms in society, claim many folks who seek to understand media roles. Put another way, what these channels do best may be to signal the presence of something worthy of our attention.
In mass communications research, this function is called the “agenda-setting effect” of the media, and it has been a popular research topic for nearly 30 years. For example, mass communication researchers explored the ability of the media to alert us to the AIDS epidemic in the 1980s (Rogers, Dearing & Chang, 1991) and, quite recently, to dimensions of the U.S. war on drugs (Gonzenbach, 1996).
This notion of media as signaling devices makes intuitive sense. The more stories the public sees about a topic, the more important that topic should seem to them. What could be simpler? But finding the effect has not been easy. It’s been so difficult, in fact, that current research raises the question of whose agenda the media actually set.
To illustrate this conundrum, let me describe for you a study of agenda-setting during the heady days of global-warming coverage from the early 1980s to the early 1990s. Craig Trumbo, now at the University of Nevada at Reno but soon to join the faculty at Cornell University in fall, was interested in whether or not media coverage influenced our judgments of the importance of the issue; the study was published by Journalism & Mass Communication Monographs in 1995.
What makes this work notable is that Trumbo decided to study a wide variety
of media and a host of different publics. And he used sophisticated time
series analyses to “see” the possibility of causality more clearly.
First, he measured the amount of global warming news (by standardized column
inches) from 1981 through the end of 1992 in:
He also counted the minutes of global-warming coverage in:
Then he turned his attention to the task of measuring the responses of several “publics.”
So what did he find?
First, when he plotted all seven variables over time, they created a
form that looked a bit like a normal curve, rising to a coverage/concern
peak between 1989 and 1990 and then declining steadily through the end of
1992, Trumbo’s last data point. Thus, all seven types of data rose
and fell together, like schooling fish.
Among newspapers, The New York Times devoted the most column inches
to global warming during the eight years (195 stories) while the Wall
Street Journal came in last (49 stories). Among the news magazines,
Newsweek was the most consistent monitor of global warming with 23
stories, while U.S. News & World Report was least with 11.
Among the TV networks, ABC World News aired 34 stories, compared to CBS Evening News’ 25 and NBC Nightly News’ 22.
And among the science press, New Scientist and Nature were by far the most assiduous attenders to global warming, with 207 and 174 stories respectively. Science News was next with 78, followed by Science with 75.
In 1981, only 38% of the public had heard of the greenhouse effect (not a synonym for global warming, of course, but a term that often accompanies global-warming stories). By 1987, that percentage had risen only to 40%, but over the next few years it reached near saturation at 86%.
But what about level of concern? Public concern about global warming rose steadily between 1987 and 1989, Trumbo found, such that 1989 found many more “extremely concerned” respondents than “moderately concerned” ones. By 1993, though, that level of concern had decayed to the point where “moderately” and “extremely” concerned groups were the same size.
Throughout the period, global warming was consistently ranked as the most important environmental problem by only 5 to 9% of respondents; that percentage peaked at 12% in November 1989 and coincided with high levels of media attention.
All well and good. But who set whose agenda in this study? Here is a brief litany of findings:
Could it really be true that years of stories about an issue such as global warming have no impact on our judgments of the importance of the issue? It’s hard to say, as measuring and tracking public concern is an expensive and difficult thing to do. Trumbo’s use of available poll data probably meant he was forced to utilize some measures that were less than ideal. But it is indeed possible that media coverage may influence our AWARENESS of an issue without having a scintilla of an effect on our sense of the IMPORTANCE of the issue. We may derive our judgments of concern from a far more complex mix of factors than just media stories.
But the effects of media coverage on policy makers—and vice versa—is worth noting. Many commentators have suggested that media may have a more pronounced impact on policy makers than on the public, and this study offers good empirical evidence for that pattern. The most important audience for media stories may indeed be the politicians.
Gonzenbach, William J. (1996) The media, the president, and public opinion:
A longitudinal analysis of the drug issue, 1984-1991. Mahwah, NJ: Erlbaum.
Rogers, Everett M., Dearing, James W., and Chang, Soonbum (1991) “AIDS
in the 1980s: The agenda-setting process for a public issue.” JOURNALISM
& MASS COMMUNICATION MONOGRAPHS 126. Trumbo, Craig (1995)”Longitudinal
modeling of public issues: An application of the agenda-setting process
to the issue of global warming.” JOURNALISM & MASS COMMUNICATION
MONOGRAPHS 152.
Sharon Dunwoody is Evjue-Bascom Professor of Journalism and Mass Communication, Head of Academic Programs, Institute of Environmental Studies, University of Wisconsin-Madison.