ABSTRACT
Nineteenth-century newspaper publishers in the United States operated in two markets at once: they sold news to readers and sold readers to advertisers. The attention market in which publishers sold readers to advertisers was constrained by lack of information; when advertising agents began to fill the coordinating role that wholesalers played in goods markets, the attention market grew rapidly and the unit costs of audience eyes fell. Advertising agents assisted advertisers in extensive advertising strategies (reach more eyes more times) and intensive strategies (reach precisely selected eyes with carefully targeted content).
