Structures of diversity of press and broadcasting systems: The institutional context of public communication in Western democracies

In modern democracies, the media are a key actor in the political process. They are the main source of information from which citizens draw their knowledge about political matters. From the perspective of the rationality of public opinion building the principle of diversity is regarded as the central norm to evaluate the performance of the media. This paper focuses on the structural aspects of media diversity. The assumption is that the institutional structure eventually affects the quality of information communicated to citizens. The objective of our study is to establish a macro-analytical framework of the diversity principle. We elaborate indicators and typologies for empirical evaluation, which are then taken to classify the media systems of advanced Western democracies (OECD countries). The empirical analysis captures the period between 1970 and 1990 (press) and 1980 and 1990 (broadcasting) when the media were undergoing rapid economic and technological changes with considerable consequences for the structure of diversity.