The authors' great achievement is that they write intelligently about press bias without descending into a conversation-killing discussion of "objective" and "subjective" journalism. That said, I wish they'd tested their theory a bit more rigorously by applying it to the British press, which is both competitive and excessively partisan. Despite the existence of the trans-Atlantic-flavored Economist and Financial Times, the four leading papers on the British newsstand—the Times, the Independent, the Guardian, and the Telegraph—contradict the Gentzkow-Shapiro thesis. Over there, competition has spawned newspapers whose major occupation is to provide a daily reaffirmation of one's worldview.
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