This paper explores the evolution of OECD imports over time, measuring their concentration across origin countries at the product level. The authors find evidence of diversification followed, in the very last years of the sample period (post-2000), by a slight re-concentration. This...

This paper explores the evolution of OECD imports over time, measuring their concentration across origin countries at the product level. The authors find evidence of diversification followed, in the very last years of the sample period (post-2000), by a slight re-concentration. This...

This paper explores the evolution of OECD imports over time and as a function of income levels, measuring the concentration of those imports across origin countries at the product level. The authors find evidence of diversification followed, in the last years of the sample period (post-2000), by...

We posit that OECD buyers are in a continuous search for best quality suppliers from developing countries. We build a simple model of adverse selection and quality screening which captures this feature. The model predicts that diversification happens by “bouts”, or temporary episodes, during...