Traditional weighted-average measures of trade distortions are widely used in analyzing global and regional reforms, despite well-known deficiencies. This paper develops and applies optimal aggregators for the real-world case of multiple countries and commodities with much more detailed...

This paper uses detailed data on bound and applied tariffs to assess the consequences of the World Trade Organization s December 2008 Modalities for tariffs levied and faced by developing countries, and the welfare implications of these reforms. The authors find that the tiered formula for...

Many trade negotiations involve large cuts in high tariffs, while allowing smaller cuts for an agreed share of politically sensitive products. The effects of these flexibilities on market access opportunities are difficult to predict, creating particular problems for developing countries in...

In the event of large swings in world food prices, countries often intervene to dampen the impact of international food price spikes on domestic prices and to lessen the burden of adjustment on vulnerable population groups. While individual countries can succeed at insulating their domestic...

The gravity model is now widely used for policy analysis and hypothesis testing, but different estimators give sharply different parameter estimates and popular estimators are likely biased because dependent variables are limited-dependent, error variances are nonconstant and missing data...

The multilateral trade system rests on the principle of nondiscrimination. The most-favored-nation (MFN) clause embodied in article one of the General Agreement on Tariffs and Trade (GATT) was the defining principle for a system that emerged in the post, Second World War era, largely in reaction...

Global commodity markets are affected by a variety of government policies that may expand or lower overall supply and as a result affect world prices for the specific products concerned. Market failures and market structures (market power along the value chain) also affect supply. This paper...

Global food prices have increased substantially since mid-2010, as have prices in many developing countries. In this study we assess the poverty impact of the price changes between June and December 2010 in twenty-eight low and middle income countries. This is done by gathering detailed...

For individual countries, variable trade barriers can be used to reduce the volatility of domestic relative to world prices. If this is done by countries accounting for a large share of the market, its effect is offset by increases in world price volatility. This study shows the nature of the...

The Special Safeguard Mechanism was a key issue in the July 2008 failure to reach agreement in the World Trade Organization negotiations under the Doha Development Agenda. It includes both price and quantity-triggered measures. This paper uses a stochastic simulation model of the world wheat...