World trade evolves at two margins. Where a bilateral trading relationship already exists it may increase through time (intensive margin). But trade may also increase if a trading bilateral relationship is newly established between countries that have not traded with each other in the past...

This paper derives a micro-founded gravity equation in general equilibrium based on a translog demand system that allows for endogenous markups and rich substitution patterns across goods. In contrast to standard CES-based gravity equations, trade is more sensitive to trade costs if the...

This paper assesses whether the sensitivity of bilateral trade volumes to various trade cost factors is constant or varies across countries. It utilizes a random coeffcients model and analyses a cross-sectional sample of bilateral trade data for 96 countries in 2005. We expect the elasticity of...

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...

We develop a new general equilibrium monopolistic competition model with variable demand elasticity, heterogeneous firms, and multiple asymmetric regions. Wages, productivity, consumption diversity, and markups across firms and markets are all endogenously determined and respond to trade...

This paper identifies a "border" effect in the absence of a border. The finding that trade between East- and West-Japan is 23.1 to 51.3 percent lower than trade within both country parts, is established despite the absence of an obvious east-west division due to historical borders, cultural...

Gravity equations have been used for more than 50 years to estimate ex post the partial effects of trade costs on international trade flows, and the well-known - and traditionally presumed exogenous - "trade-cost elasticity" plays a central role in computing general equilibrium trade-flow and...

We propose and apply a new theory-consistent algorithm, which uses disaggregated inter-city trade data to identify a pyramidic city system with central places and associated hinterlands. Because central places possess more industries than the cities in their hinterlands, and because industries,...

Firms adjust to differences in market size and demand uncertainty by changing the frequency and size of their export shipments. In our inventory model, transportation costs and optimal shipment frequency are determined on the basis of demand as well as inventory and per shipments costs. Using a...

We introduce unemployment and endogenous selection of workers into different skill-classes in a trade model with two sectors and heterogeneous firms. This allows us to study the distributional consequences and the skill-specific unemployment effects of trade liberalization. We show that the...