These results show interesting differences across issues. Everyone has experience with prices. An effect found in the first part of its life as an issue, then later not. After people become accustomed to the issue, the media have less of an effect. Show graphs of four issues Ask students working in twos to identify which graphs seem to be showing an agenda setting effect and which not.
Media often influence each other.
TV networks in particular are quite similar. Mass media sponsor polls about AIDS, for example, then do stories about the results. If media have the power to set the public agenda, and if the media agenda is only loosely tied to public interests and social reality, it is important to know where the media agenda does come from.