2004年-世界发展银行全球_Welfare_Impacts_of_Chinas_Accession_to_the_World_Trade_Organization_30页_213kb

Summary of "Welfare Impacts of China's Accession to the World Trade Organization"

Core Content

This article by Shaohua Chen and Martin Ravallion analyzes the welfare impacts of China's accession to the World Trade Organization (WTO) in 2001, using data from China's national rural and urban household surveys. The study employs a general equilibrium model to estimate the effects of trade policy changes, such as tariff reductions and export subsidy removal, on commodity and factor prices. These price changes are then used to calculate welfare impacts at the household level using a first-order approximation method.

The key insight is that while the overall impact on inequality and poverty in China is negligible, there are significant heterogeneous effects across different household types and regions. These differences are attributed to variations in consumption patterns, income sources, and geographic location.

Main Viewpoints

• Overall Welfare Impact: The study finds that the average welfare gain is about 1.5% of mean income, all occurring in the period leading up to WTO accession. There is almost no effect on inequality, with the Gini index increasing only slightly from 39.3% to 39.5%.

• Heterogeneous Impacts: The effects of trade reform are not uniform across households. Some groups experience gains while others face losses, depending on their consumption behavior, income sources, and geographic location. These disparities suggest that compensatory policies may be necessary to address the uneven distribution of benefits and costs.

• Methodological Approach: The authors use a hybrid method, combining general equilibrium price and wage changes with detailed household survey data. This avoids the limitations of cross-country comparisons, which are often plagued by data quality and identification issues. The approach also minimizes aggregation by applying the general equilibrium results to all surveyed households.

• Limitations of the Method: The study acknowledges that the first-order approximation assumes small price changes and does not account for non-linear effects or non-convexities in consumption and production. Additionally, it uses income as a proxy for welfare, which may not fully capture geographic differences in cost of living.

Key Information

Data and Methodology

• The study uses data from the 1999 Rural and Urban Household Surveys conducted by China's National Bureau of Statistics (NBS), covering 67,900 rural households and 16,900 urban households.
• The GTAP model is used to estimate price and wage changes, which are then applied to the survey data.
• The model includes 25 sectors and three types of labor (unskilled farm, unskilled nonfarm, and skilled nonfarm).
• Sampling weights are adjusted to reflect the actual population distribution, using data from the China Statistical Yearbook.

Price and Wage Changes

• The GTAP model estimates predicted price and wage changes for the periods 1995–2000 and 2001–2007.
• Consumer and wholesale prices are adjusted to reflect the impact of trade reforms.
• The model accounts for own-production activities and government budget constraints, providing a more comprehensive view of the economic effects.

Welfare Impact Calculation

• The welfare impact is calculated using the formula:
  $$
  g_{i} = \sum_{j = 1}^{m} \left[ p_{ij}^{s} q_{ij}^{s} \frac{d p_{ij}^{s}}{p_{ij}^{s}} - p_{ij}^{d}(q_{ij}^{d} + z_{ij}) \frac{d p_{ij}^{d}}{p_{ij}^{d}} \right] + \sum_{k = 1}^{n} \left(w_{k} L_{ik}^{s} \frac{d w_{k}}{w_{k}}\right)
  $$
• This formula weights the changes in prices and wages by their expenditure and income shares.
• Net revenue and mean welfare change are calculated for each household type and sector.

Results Overview

• Rural households generally experience positive net revenue from some sectors (e.g., feedgrains, vegetables and fruits), but negative impacts in others (e.g., plant-based fibers, other manufactures).
• Urban households face larger negative impacts, particularly in sectors like beverages and tobacco, commercial services, and other services.
• Skilled labor in urban areas benefits the most, with significant gains in income and welfare.
• Land and capital also show small positive impacts for rural households, but urban households are not affected.

Poverty and Inequality

• The poverty headcount index is calculated for the official poverty line and for $1/day and $2/day poverty lines.
• The study shows that poverty would have been slightly higher in 1999 without the trade reforms, and poverty is predicted to rise slightly in 2001–2007 due to the remaining tariff changes.
• The distributional effects are most pronounced in rural-urban differences and income levels.

Conclusion

China's WTO accession led to negligible aggregate impacts on inequality and poverty, but substantial heterogeneous effects at the household level. The study highlights the importance of analyzing these differences to better understand the distributional consequences of trade reforms and to inform targeted policy responses. The method used provides a more accurate and detailed picture of welfare changes than cross-country comparisons, which are often limited by data and specification issues.