Assessing Global Computable General Equilibrium Model Validity Using Agricultural Price Volatility

Computable General Equilibrium (CGE) models are commonly used for global agricultural market analysis. Concerns are sometimes raised, however, about the quality of their output since key parameters may not be econometrically estimated and little emphasis is generally given to model assessment. This article addresses the latter issue by developing an approach to validating CGE models based on the ability to reproduce observed price volatility in agricultural markets. We show how patterns in the deviations between model predictions and validation criteria can be used to identify the weak points of a model and guide development of improved specifications with firmer empirical foundations.     

Market Growth, Structural Change, and the Gains from the Uruguay Round

It is found that market growth and structural changes will affect the results of quantitative analyses of the Uruguay Round. Rapid economic growth in Asia, and relatively deeper cuts in protection in that region, result in larger proportionate welfare gains in the year 2005 than in the year 1992. It is also found that changing comparative advantage, and shifts in global demand, result in substantial changes in the restrictive effects of the bilateral quotas on textiles and apparel. Accounting for the factors associated with market growth and structural change adds 30% to the estimates of global welfare gains from the Uruguay Round.     

Procompetitive Effects of Foreign Competition on Domestic Markups

A short-run model for estimating the procompetitive effects of foreign competition on markups in an oligopolistic, domestic industry is developed and estimated using data on the Australian automobile industry. Estimates reveal that these effects are rather large and cannot be ignored when predicting the effects of a shock affecting foreign costs. These estimates can also facilitate inferences about the nature of interfirm rivalry.     

Land Use in the 21st Century: Contributing to the Global Public Good

This paper focuses on the evolution of global public goods related to the world's land resources over the course of the 21st century, their potential impacts on the world's poorest households, as well as prospects for policy interventions aimed at enhancing these outcomes. It begins with global scale projections to 2100 of land use and associated goods and services, including food, fuel, timber, greenhouse gas emissions, carbon sequestration and biodiversity. This is followed by in‐depth discussion of each of these services and the challenges of providing these public goods in sufficient quantities to advance societal welfare—especially that of the world's poorest households. The paper concludes with a discussion of policies aimed at promoting the provision of land‐based public goods and how they could be altered to be more pro‐poor. Within this context, the paper argues that access to geospatial analysis tools and information on climate, land use and tenure, poverty and environmental indicators will become increasingly valuable to both public and private decision makers.     

Impacts of trade reform: sensitivity of model results to key assumptions

The WTO’s Doha Development Agenda has generated demand for estimates of the potential economic consequences of global trade reform. Recent improvements in the GTAP dataset have provided a much better representation of tariff restrictions as of 2001. However, despite its use by most global trade modelers, substantial differences in results emerge from different computable general equilibrium exercises. To help understand these differences, this paper examines the sensitivity of full global and regional trade liberalization results from the GTAP model, using the GTAP version 6.1 database, to different assumptions about factor mobility, fiscal neutrality, macro-economic closure, and trade (Armington) elasticities.

Why Isn't the Doha Development Agenda more Poverty Friendly?

Critics of the Doha Development Agenda rightly point to the lack of aggressive reform in wealthy countries for its role in dampening developing country gains. The authors find that the absence of tariff cuts on staple food products in developing countries also critically limits poverty reduction in those countries. Based on their analysis of the impacts of multilateral trade policy reforms in a sample of 15 developing countries, they find there is some evidence of poverty increases amongst the poor who work in agriculture when they lose protection for their earnings. However, these effects are minimized when agricultural tariffs are cut in all developing countries, and when the impact of lower food prices on low income consumers is taken into account in their 15 country sample.     

The research cost of adapting agriculture to climate change: A global analysis to 2050

Investments in agricultural research and development (R&D) made over the next few decades will likely prove critical in offsetting adverse climate change impacts on the global food system. In this study, we offer cost estimates of public R&D-led adaptation to climate change grounded in an explicit framework relating the flow of annual R&D expenditures to building knowledge capital and thereby raising productivity in agriculture. Our research uses a comprehensive collection of historical public agricultural R&D expenditure and a literature review of elasticity estimates linking knowledge stocks to agricultural productivity growth for key world regions. Given climate-driven crop yield projections generated from extreme combinations of crop and global circulation models, we find that offsetting crop yield losses projected by climate and crop models over 2006–2050 would require increased R&D adaptation investments of between $187 billion and $1,384 billion (in 2005 $PPP) if we invest between 2020 and 2040. This is 16–118% higher than global R&D investment if present spending trends continue. Although these costs are significant, worldwide R&D-led climate adaptation could offer favorable economic returns. Moreover, R&D-led adaptation could deliver gains in food security and environmental sustainability by mitigating food price increases and slowing cropland expansion.     

Predicting within country household food expenditure variation using international cross-section estimates

International cross-section demand systems have not been tested on their ability to accurately predict within country consumption expenditures. This paper reports on such a validation exercise for the case of food budget share predictions across expenditure percentiles within Bangladesh.     

FACTOR MARKET INCIDENCE OF AGRICULTURAL TRADE LIBERALIZATION: SOME ADDITIONAL RESULTS

Liberalization of trade implies changes in producer prices, which has consequences for farm income, agricultural employment and asset values. The relative incidence of the effect of changes in prices on fixed factors depends on the rclative magnitude of the Morishima elasticities of substitution in agricultural production.     

Productivity growth and convergence in crop, ruminant, and nonruminant production: measurement and forecasts

Projections of future productivity growth rates in agriculture are an essential input for a great variety of tasks, ranging from development of an outlook for global commodity markets to the analysis of interactions between land use, deforestation, and ecological diversity. Yet solid projections for these variables have proven elusive—particularly on a global basis. This is due, in no small part, to the difficulty of measuring historical total factor productivity growth. Consequently, most productivity projections are based on partial factor productivity measures that can be quite misleading. The purpose of this work is to provide worldwide forecasts of agricultural productivity growth till the year 2040 based on the latest time series evidence on total factor productivity growth for crops, ruminants, and nonruminant livestock. The results suggest that most regions in the sample are likely to experience larger productivity gains in livestock than in crops. Within livestock, the nonruminant sector is expected to continue to be more dynamic than the ruminant sector. Given the rapid rates of productivity growth observed recently, nonruminant and crop productivity in developing countries may be converging to the productivity levels of developed countries. For ruminants, the results show that productivity levels in developing countries are likely to be diverging from those in developed countries.