Krugman often writes for The New York Times.
New Trade Theory. suggests there are two reasons that the idea of comparative advantage doesn't represent reality; consumers prefer to have choices between brands or variations of products, and production efficiency increases with economies of scale.
Economies of scale.
The Royal Swedish Academy of Sciences has decided to award the Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel for 2008 to Paul Krugman “for his analysis of trade patterns and location of economic activity”.
Krugman defined the New Economic Geography as the location theory of production, just as the concept of the classical location theory, which is proposed to explain the mechanism of formation and evolution of the economic spatial structure.