世界银行-重新定义全球多维贫困衡量，以尼日利亚数据为例（英）-2023.10-50页_2mb

Reconceptualizing Global Multidimensional Poverty Measurement with Nigerian Data

Key Findings

• Global multidimensional poverty measures (MPMs) face criticism for not aligning with preference theory and failing to adequately capture key well-being dimensions, including mortality.
• The report proposes theoretical refinements to the Alkire-Foster methodology, enabling better identification of "extremors" (individuals with severe deprivations in one dimension) and "cumulators" (individuals with moderate deprivations across multiple dimensions).
• Integration of mortality's direct impact enhances the measurement of well-being losses, with premature mortality contributing significantly to overall poverty in Nigeria.
  -Aggregating dimensions consistently reduces identification errors compared to relying solely on monetary poverty indicators.

Methodology

• Refined Alkire-Foster Method: Defines extreme and moderate deprivations across multiple dimensions, accounting for depth of deprivation.
• Mortality Integration: Uses Poverty-Adjusted Life Expectancy (PALE) to combine quantity of life and quality of life, with a normative weight reflecting trade-offs.
• Data handling includes careful mapping of dimensions like health, housing, security, and education, with attention to data constraints and imputation where necessary.

Illustration with Nigerian Data (2019)

• Uses Nigeria Living Standards Survey and complementary data sources to analyze 36 states.
• Findings:
  • Multidimensional poverty incidence (51.9%) exceeded monetary poverty (40.5%), revealing a significant bias when ignoring non-monetary deprivations.
  • Health and housing emerged as major contributors to non-monetary deprivation, while mortality significantly affected well-being losses.
  • Well-being rankings across states could be substantially altered when accounting for non-monetary dimensions, even when monetary poverty varies widely.

Policy Implications

• The refined MPM provides a more nuanced view of poverty, helping to identify the most pressing needs for social protection.
• Better identification of "omitted poor" (non-monetary poor not captured by monetary measures) informs targeted interventions.
  -Higher normative weights for mortality could shift policy priorities toward addressing lifespan inequality.
• Empirical results underscore the need for more robust data and careful calibration to avoid misallocation of social budgets.

Conclusions and Open Questions

• The paper advocates for prioritizing indirect utility over simplistic aggregation to improve MPM alignment with theoretical preferences.
• Challenges include data limitations, defining plausible trade-offs for mortality, and ensuring the method's applicability at scale.
• Further empirical research is needed to refine mappings and norms, particularly for global adaptation.