This paper advocates a new way of thinking about goods trade in an open economy macro model. It develops a simple method for analyzing trade costs that are heterogeneous among a continuum of goods, and it explores how these costs determine the endogenous decision by a seller of whether to trade...

Long-run cross-country price data exhibit a puzzle. Today, richer countries exhibit higher price levels than poorer countries, a stylized fact usually attributed to the Balassa- Samuelson effect. But looking back fifty years, this effect virtually disappears from the data. What is often assumed...

This paper develops a two-country macro model with endogenous tradability to study features of international economic integration. Recent episodes of integration in Europe and North America suggest some surprising observations: while quantities of trade have increased significantly, especially...