What drives media slant? Evidence from U.S. daily newspapers

Boris pointed me to this paper by Matthew Gentzkow and Jesse Shapiro. Here’s the abstract:

We [Gentzkow and Shapiro] construct a new index of media slant that measures whether a news outlet’s language is more similar to a congressional Republican or Democrat. We apply the measure to study the market forces that determine political content in the news. We estimate a model of newspaper demand that incorporates slant explicitly, estimate the slant that would be chosen if newspapers independently maximized their own profits, and compare these ideal points with firms’ actual choices. Our analysis confirms an economically significant demand for news slanted toward one’s own political ideology. Firms respond strongly to consumer preferences, which account for roughly 20 percent of the variation in measured slant in our sample. By contrast, the identity of a newspaper’s owner explains far less of the variation in slant, and we find little evidence that media conglomerates homogenize news to minimize fixed costs in the production of content.

It appears that newspapers are more liberal in liberal cities and more conservative in conservative cities.

I like the idea of what they are doing but I have some difficulties with the implementation. For example, they consider the phrases, “death tax,” “tax relief,” “personal account,” and “war on terror”” (identifed as strongly Republican), and “”estate tax, ”“tax break, ”“private account, ”and “war in Iraq”” (identifed as strongly Democratic). What bothers me here is that these terms have different factual implications. Just going through these one at a time:

– “Estate tax” is, I believe, the standard term. “Death tax” is pretty much explicitly partisan, designed to shift the debate.
– “Tax relief” and “tax break” both sound descriptive to me. (I wouldn’t mind either one right about now, actually…) I’ll take their word for it that the Dems use one of these and the Reps use the other, but I wouldn’t call these ideologically slanted.
– “Personal account” and “private account” sound the same to me also! Again, these may differ in the world of Social Security focus groups, but neither sounds slanted.
– “The war on terror” and “the war in Iraq” are both happening. They overlap but are not identical. Again, I don’t see a slant. A Republican could argue that the war in Iraq is a key part of the war on terror, a Democrat could argue that the war in Iraq is a distraction from the war on terror, but both phrases seem legitimate to me.