Exploring the dynamics in the environmental discourse: the longitudinal interaction among public opinion, presidential opinion, media coverage, policymaking in 3 decades and an integrated model of media effects

Using data on environmental issues drawn from 41 series of poll questions and federal outlay in 43 years (1965–2007) and a content analysis of newspaper articles, television news summaries, and presidential documents in 28 years (1980–2007), with the multivariate Granger causality test based on vector autoregression models and bivariate Granger causality (F and χ2) tests, the study finds that public opinion has little influences on federal environmental expenditure in the past several decades, if the interaction from the president and the media is also considered in the analysis. It also finds that for the presidents, the media, and the public, their agendas (volume of information) cause a change in their attitudes (tone toward the environment) and that the casualties in the agenda and frame building and setting processes are essentially confirmed with the multivariate test, but feedback influences are also identified through the bivariate tests. The multivariate test also shows an influence from the presidential agenda to the public agenda on environmental issues, with no influence identified the other way around. The implications of the proposed five-level integrated model of media effects are also discussed.