Valdis Krebs presents this map of purchasing habits for political books, using the techniques of cluster analysis. Krebs’ main point is that the books divide readers into two sharply separate clusters, color-coded on the assumption that one group of readers are Democrats and the other are Republicans. The diagram also coincides with the standard left-right coding.
I have a couple of observations on this. The first is the trivial one that this color-coding is the exact opposite of the one that would naturally be used in Australia or the UK (back in my days as a folksinger, one of my more successful pieces (this is a highly relative term( was about a Labour leader who “went in [to office] Red and came out Blue”. Without wanting to load too much on to arbitrary signifiers, this does seem to me to support my view that there’s a bigger gulf between liberals and the radical left in the US than elsewhere. Even if the mainstream left party in other countries does not adopt the red banner of Marxism there’s sufficient continuity along the political spectrum to make it’s adoption by the right unlikely.
The second thing that’s striking is that, on the left-right orientation, I come out as a moderate. I’ve read nearly all the blue books that are within one or two links of the red zone, and none of those on the far left of the diagram. On the right, I’ve read only Letters to a Young Conservative .
Looking again at the titles of the books I’ve read, while there’s a vaguely leftish slant to them, one could scarcely call either Clash of Civilisations or Elusive Quest for Growth supportive of the left. The striking thing is that these are mostly the serious books, while those on either side are mostly lightweight polemics (I’m inferring this from the reviews I’ve read of some of them and the titles of the others). But it would appear from the cluster analysis that those who read leftwing partisan diatribes also tend to read serious books (and vice versa) while those who read rightwing partisan diatribes don’t read anything else.
In terms of the debate that’s been going on for some time about the relative intellectual capacity of the left and the right, the cluster analysis seems to imply that the left is doing a lot more to enhance its intellectual capacity than is the right.
(Hat tip to Alex Tabarrok at Marginal Revolution)