印度2012年至2022年至2023年的贫困趋势：方法论说明（英）

P a g e2|78A reproducibility package for this report is available inthe Reproducible Research Repository athttps://reproducibility.worldbank.org/index.php/catalog/280 This work is a product of the staff of the World Bank with external contributions.Acore World BankIndiaPoverty and Equityteam worked undertheguidanceofXimena del Carpio(Practice Manager,Poverty and Equity, South Asia Region).The teamincludedNancyPuranbhaiDevpura (ResearchAnalyst),Maria Fernanda Gonzalez Icaza (Economist),Diego Lestani (Extended Term Consultant),Julia Liniado (Consultant),Nishtha Kochhar (Economist),Nandini Krishnan(Lead Economist),Naresh Kumar(Economist), and Ayago Wambile (Senior Economist).Throughout, the teambenefitedfrom technical review and guidance froman advisorygroupcomprising bothexternal andWorldBankmembers,includingLaura Moreno Herrera (Senior Data Scientist, World Bank),Himanshu(Professor,Jawaharlal Nehru University),Peter Lanjouw(Professor,Vrije UniversiteitAmsterdam),Juan Munoz (Sistemas Integrales),Sergio Olivieri (Senior Economist, World Bank), Jaime FernandezRomero (Data Scientist, World Bank),andNobuo Yoshida (Lead Economist, World Bank).The teambenefited from technical consultations with theWorld Bank’sGlobal Poverty Working Group (GPWG)and thePoverty GlobalDepartment’s Advisory Group. P a g e3|78 ContentsExecutive Summary............................................................................................................................71.Introduction.......................................................................................................................112.Background on poverty measurement in India.....................................................................122.1National poverty lines.........................................................................................................122.2International poverty lines..................................................................................................123.Background on the CES and caveats on comparability.........................................................143.1Coverage and timeline for data collection............................................................................143.2Transition from PAPI to CAPI for data collection in 2022-23...................................................143.3Sample design in 2022-23 and changes from the 2011-12 CES.............................................153.4Changes in the recall period between 2011-12 and 2022-23.................................................173.5Changes in the questionnaires between 2011-12 and 2022-23..............................................183.6Implications and threats to comparability............................................................................184.Methodology to construct a real welfare aggregate for India.................................................214.1Theoretical considerations on welfare measurement...........................................................214.2Constructing a real welfare aggregate using 2011-12 and 2022-23 CES.................................224.3Data cleaning and harmonization........................................................................................244.4Nominal expenditure aggregate..........................................................................................244.5From expenditures to welfare: Adjusting the nominal expenditure aggregate.........................264.5.1Re-valuation of subsidized items.........................................................................................27(a)Free and subsidized food....................................................................................................27(b)Free non-food items-school uniforms and footwear............................................................304.5.2Exclusion ofpurchase value of durable goods......................................................................324.5.3Exclusion of certain non-food non-durable expenditures......................................................344.5.4Exclusion of medical hospitalization expenses....................................................................364.5.5Housing services................................................................................................................364.6From nominal to real: Constructing the real welfare aggregate..............................................384.6.1Intra-temporal price adjustment within survey year..............................................................394.6.2Spatial price adjustment.....................................................................................................404.6.3Inter-temporal adjustment across years..............................................................................414.7Neteffect of all adjustments on the welfare aggregate.........................................................425.Poverty and Inequality Trends, 2011-12 and 2022-23............................