Retail prices of major drugs like cocaine and heroin have declined dramatically during the last two decades. This price decline has tended to offset the effects of drug policies aimed at reducing drug use in major industrial countries. The main finding of this paper is that the decline in the...

Within a standard gravity framework I explore the impact of country size and trade liberalisation on extensive and intensive margins of imports across broad categories of goods. This allows testing hypotheses from two distinct strands of the trade literature, i.e., vertical integration versus...

In many markets in developing countries, especially in remote areas, middlemen are thought to earn excessive profits. Non-profits come in to counter what is seen as middlemen's market power, and rich country consumers pay a fair-trade premium for products marketed by such non-profits. This paper...

Helpman, Melitz and Rubinstein (2008) derive gravity equations to estimate effects of trade barriers on the intensive and extensive margins of trade. They exploit the frequency of zeros in aggregate bilateral trade data to identify effects on the extensive margin and to obtain controls for firm...

Many empirical studies have examined the cyclical nature of the markup ratio. Until recently, few have attempted to ascertain the changes in the markup over a longer time horizon. These changes are of no less interest in view of the posited effects of increasing import competition and lower...