Take my comments with as much salt as you like, given that I tout no formal degrees in economics, but think that Krugman fairly well botched the "network externalities" issue. The mere fact that he calls them "externalities" reveals error. Liebowitz & Margolis convincingly argue that "network *effects*" more properly fits the phenomena. We amatuers may regard that as an arcane distinction, but surely professional economists should use consistent and accurate terminology.
Krugman has moreover made highly suspect and hotly controverted claims of having pioneered the idea of network effects, has bought into the QWERTY myth too uncritically, and has failed to revisit his views in the face of new and contradictory evidence.
So goes my opinion--an opinion you may rightly discount--of Krugman's work in one area. He may get a great deal right on other fronts, of course, and even good economists make mistakes from time to time. Query, though, whether Krugman knows much about biology. I recall thinking that his criticisms of bioeconomics were about half-right.
>Paul Krugman is a very good economist.