MARKET FORCES FORCE:

A natural hypothesis is that a media outlet's perspective reflects the ideology of its owner. Indeed, much regulatory policy is premised on precisely this view. Policy makers sometimes take a jaundiced view of media consolidation on the grounds that high levels of cross-ownership reduce the range of political perspectives available to consumers.

From their study of newspapers, however, Mr. Gentzkow and Mr. Shapiro, find little evidence to support this hypothesis. After accounting for confounding factors like geographic proximity, they find that two newspapers with the same owner are no more likely to be ideologically similar than two random papers. Moreover, they find no correlation between the political slant of a paper and the owner's ideology, as judged by political donations.

So, if not the owner's politics, what determines whether a newspaper leans left or right? To answer this question, Mr. Gentzkow and Mr. Shapiro focus on regional papers, ignoring the few with national scope, like The Times. They find that potential customers are crucial.

If a paper serves a liberal community, it is likely to lean left, and if it serves a conservative community, it is likely to lean right. In addition, once its political slant is set, a paper is more likely to be read by households who share its perspective. [...]

The bottom line is simple: Media owners generally do not try to mold the population to their own brand of politics. Instead, like other business owners, they maximize profit by giving customers what they want.

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