The information about ratings and their use, outlined above, has shown us how audience behaviours are transformed into measurable statistics that allow audiences to be traded as commodities by the broadcasting industries. The system of audience measurement and public opinion polling, devised in the first half of the twentieth century, pioneered a system of continuous audience monitoring using representative population sampling. In the 1990s, the applicability of these systems outside the broadcasting environment expanded dramatically because of digitization and the development of computer programs designed specifically to process the data on entertainment exposures and to track audience movements from programme to product, from channel to supermarkets, medium to shopping mall.作者: kristall325 时间: 2008-1-4 13:22