2004年-世界发展银行全球_Pro-Poor_Growth__A_Primer_28页_246kb

Pro-Poor Growth: A Primer Summary

Core Content

This paper by Martin Ravallion explores the concept of pro-poor growth, examining its definition, measurement, and the factors that influence its effectiveness in reducing poverty. It addresses the debate around whether economic growth is inherently pro-poor and the role of inequality in shaping the outcomes of growth.

Definitions of Pro-Poor Growth

There are two main definitions of pro-poor growth:

1. Pro-poor growth as distributional shift: This refers to a situation where the distributional changes during economic growth benefit the poor more than the non-poor. It focuses on inequality and requires that the poor's incomes grow faster than those of the non-poor.

2. Pro-poor growth as poverty reduction: This definition emphasizes whether poor people benefit in absolute terms, regardless of the distributional changes. It is based on a poverty measure, such as the headcount index or the Watts index, and reflects the actual change in poverty levels.

How to Measure Pro-Poor Growth

• Headcount index: Measures the proportion of the population living below the poverty line.
• Poverty gap index: Reflects the average shortfall of the poor from the poverty line.
• Watts index: A measure of poverty that accounts for inequality among the poor and is considered one of the best poverty measures.
• Growth incidence curve: A tool that shows the growth rate at each percentile of the income distribution, helping to identify whether growth is pro-poor.
• Rate of pro-poor growth: Defined as the mean growth rate of the poor, calculated by multiplying the ordinary growth rate by a distributional correction factor that reflects the change in poverty relative to a neutral distribution.

The paper also introduces the concept of distributional correction, which adjusts the ordinary growth rate to reflect how much the distribution of income affects poverty reduction.

Is Growth Typically Pro-Poor?

• Empirical evidence suggests that economic growth is typically pro-poor, especially by the second definition, which focuses on absolute poverty reduction.
• Growth tends to be distribution neutral on average, meaning that inequality does not necessarily change with growth.
• However, the impact of growth on poverty varies depending on the initial level of inequality and how inequality changes over time.
• In the 1990s, the global headcount of poverty declined, and this trend was largely driven by growth in large countries like China and India.
• In contrast, some poor countries with low growth have seen slower progress in poverty reduction.

What Makes Growth More Pro-Poor?

1. Initial inequality:

   • In countries with high initial inequality, the poor tend to benefit less from economic growth.
   • A lower initial Gini index (i.e., less inequality) correlates with a higher rate of poverty reduction.
   • The paper presents a model showing that the rate of poverty reduction is proportional to the distribution corrected growth rate, which is the product of the ordinary growth rate and a term based on initial inequality.

2. Changes in inequality:

   • Falling inequality during growth can significantly enhance poverty reduction.
   • Rising inequality can undermine the effectiveness of growth in reducing poverty.
   • For example, in China, the rate of pro-poor growth is five times higher than in India, even though both have similar growth rates, due to differences in distributional shifts.

3. Elasticity of poverty to growth:

   • The elasticity of poverty to growth is negative and varies with initial inequality.
   • For the $1/day poverty rate, the elasticity is around -2 when measured from survey data, and -1.3 when measured from national accounts.
   • The model suggests that higher initial inequality reduces the effectiveness of growth in reducing poverty.

Key Findings

• Pro-poor growth is not guaranteed by economic growth alone; it depends on how the benefits of growth are distributed.
• High inequality countries may require higher growth rates to achieve significant poverty reduction.
• Distributional shifts that favor the poor can lead to a higher rate of pro-poor growth than the ordinary growth rate.
• China and India have been key in reducing global poverty, but Sub-Saharan Africa has not made similar progress.
• Poverty reduction is more responsive to changes in inequality than to changes in growth rates themselves.

Policy Implications

• Achieving higher growth rates is important for poverty reduction, but it is not sufficient.
• Maintaining low inequality is crucial in countries where growth is likely to be distribution neutral.
• Investment in infrastructure and public goods (e.g., education, health, and access to assets) can help the poor benefit more from growth.
• Future research should focus on the specific factors influencing the growth elasticity of poverty, including the role of initial conditions and policy reforms.

Conclusion

Pro-poor growth is not a given with economic growth but is influenced by the initial level of inequality and how inequality evolves over time. While growth is typically associated with poverty reduction, the extent of this reduction depends on the distributional impact of growth. Therefore, policy efforts should not only focus on growth but also on reducing inequality and improving access to opportunities for the poor.