Another contribution of agenda-setting is to show the power of media. Since the study of 1940 presidential election in Erie County, Ohio, by Paul Lazarsfeld and his colleagues, little evidence of mass communication effects was found over the next twenty years. In 1960, Joseph Klapper's "Effects of Mass Communication" also declared the limited effect of media. Agenda-setting caused a paradigm shift in the study of media effects from persuading to informing by its connection of media content and its effects on the public.