Publication:
SAE - A Stata Package for Unit Level Small Area Estimation

Loading...
Thumbnail Image
Files in English
English PDF (1.23 MB)
1,678 downloads
English Text (115.49 KB)
69 downloads
Date
2018-10
ISSN
Published
2018-10
Author(s)
Nguyen, Minh Cong
Zhao, Qinghua
Editor(s)
Abstract
This paper presents a new family of Stata functions devoted to small area estimation. Small area methods attempt to solve low representativeness of surveys within areas, or the lack of data for specific areas/sub-populations. This is accomplished by incorporating information from outside sources. Such target data sets are becoming increasingly available and can take the form of a traditional population census, but also large scale administrative records from tax administrations, or geospatial information produced using remote sensing. The strength of these target data sets is their granularity on the subpopulations of interest, however, in many cases they lack the ability to collect analytically relevant variables such as welfare or caloric intake. The family of functions introduced follow a modular design to have the flexibility with which these can be expanded in the future. This can be accomplished by the authors and/or other collaborators from the Stata community. Thus far, a major limitation of such analysis in Stata has been the large size of target data sets. The package introduces new mata functions and a plugin used to circumvent memory limitations that inevitably arise when working with big data. From an estimation perspective, the paper starts by implementing a methodology that has been widely used for the production of several poverty maps.
Link to Data Set
Citation
Nguyen, Minh Cong; Corral, Paul; Azevedo, Joao Pedro; Zhao, Qinghua. 2018. SAE - A Stata Package for Unit Level Small Area Estimation. Policy Research Working Paper;No. 8630. © World Bank. http://hdl.handle.net/10986/30650 License: CC BY 3.0 IGO.
Associated URLs
Associated content
Report Series
Report Series
Other publications in this report series
  • Publication
    The Macroeconomic Implications of Climate Change Impacts and Adaptation Options
    (Washington, DC: World Bank, 2025-05-29) Abalo, Kodzovi; Boehlert, Brent; Bui, Thanh; Burns, Andrew; Castillo, Diego; Chewpreecha, Unnada; Haider, Alexander; Hallegatte, Stephane; Jooste, Charl; McIsaac, Florent; Ruberl, Heather; Smet, Kim; Strzepek, Ken
    Estimating the macroeconomic implications of climate change impacts and adaptation options is a topic of intense research. This paper presents a framework in the World Bank's macrostructural model to assess climate-related damages. This approach has been used in many Country Climate and Development Reports, a World Bank diagnostic that identifies priorities to ensure continued development in spite of climate change and climate policy objectives. The methodology captures a set of impact channels through which climate change affects the economy by (1) connecting a set of biophysical models to the macroeconomic model and (2) exploring a set of development and climate scenarios. The paper summarizes the results for five countries, highlighting the sources and magnitudes of their vulnerability --- with estimated gross domestic product losses in 2050 exceeding 10 percent of gross domestic product in some countries and scenarios, although only a small set of impact channels is included. The paper also presents estimates of the macroeconomic gains from sector-level adaptation interventions, considering their upfront costs and avoided climate impacts and finding significant net gross domestic product gains from adaptation opportunities identified in the Country Climate and Development Reports. Finally, the paper discusses the limits of current modeling approaches, and their complementarity with empirical approaches based on historical data series. The integrated modeling approach proposed in this paper can inform policymakers as they make proactive decisions on climate change adaptation and resilience.
  • Publication
    Global Poverty Revisited Using 2021 PPPs and New Data on Consumption
    (Washington, DC: World Bank, 2025-06-05) Foster, Elizabeth; Jolliffe, Dean Mitchell; Ibarra, Gabriel Lara; Lakner, Christoph; Tettah-Baah, Samuel
    Recent improvements in survey methodologies have increased measured consumption in many low- and lower-middle-income countries that now collect a more comprehensive measure of household consumption. Faced with such methodological changes, countries have frequently revised upward their national poverty lines to make them appropriate for the new measures of consumption. This in turn affects the World Bank’s global poverty lines when they are periodically revised. The international poverty line, which is based on the typical poverty line in low-income countries, increases by around 40 percent to $3.00 when the more recent national poverty lines as well as the 2021 purchasing power parities are incorporated. The net impact of the changes in international prices, the poverty line, and new survey data (including new data for India) is an increase in global extreme poverty by some 125 million people in 2022, and a significant shift of poverty away from South Asia and toward Sub-Saharan Africa. The changes at higher poverty lines, which are more relevant to middle-income countries, are mixed.
  • Publication
    Geopolitical Fragmentation and Friendshoring
    (Washington, DC: World Bank, 2025-06-26) Grover, Arti; Vézina, Pierre-Louis
    This paper examines the relationship between geopolitical fragmentation and friendshoring of foreign investments over time, countries, and sectors. The analysis uses comprehensive data on foreign direct investments covering greenfield projects, mergers and acquisitions, and stocks of affiliates, as well as data on four alternative measures of geopolitical distance between countries. The gravity estimations suggest that, first, geopolitical differences have a negative effect on foreign investments and the magnitude has heightened in the post-pandemic period compared to a decade ago. Second, it is primarily the companies from advanced Western economies whose foreign investment decisions are increasingly shaped by friendshoring forces. Finally, the paper shows that friendshoring is not only confined to strategic industries, implying that allocations of foreign direct investments may not solely reflect national security or resilience considerations.
  • Publication
    Soaring Food Prices Threaten Recent Economic Gains in the EU
    (Washington, DC: World Bank, 2025-07-02) Robayo, Monica; Lucchetti, Leonardo Ramiro; Delgado-Prieto, Lukas; Badiani-Magnusson, Reena
    The surge in food prices following the 2021 economic rebound has become a significant concern for households, particularly low-income ones, in Bulgaria, Croatia, Poland, and Romania. Food price inflation, which surpasses general inflation rates, risks worsening poverty and food insecurity in these countries. This paper explores the distributional impacts of rising food prices and the effectiveness of government response measures. Low-income households, who allocate a larger share of their income to food, are disproportionately affected and are struggling to cope with unexpected expenses, leading to increased difficulties in accessing proper nutrition. Simulations indicate that rising food prices contribute to higher poverty rates and greater income inequality, especially among vulnerable populations. They also suggest that the main poverty-targeted social assistance schemes offer critical support for the extreme poor, but expanding both coverage and benefits is vital to shield all at-risk individuals. Targeted policies that balance immediate relief with long-term resilience-building are essential to addressing the challenges posed by escalating food prices.
  • Publication
    Disentangling the Key Economic Channels through Which Infrastructure Affects Jobs
    (Washington, DC: World Bank, 2025-04-03) Vagliasindi, Maria; Gorgulu, Nisan
    This paper takes stock of the literature on infrastructure and jobs published since the early 2000s, using a conceptual framework to identify the key channels through which different types of infrastructure impact jobs. Where relevant, it highlights the different approaches and findings in the cases of energy, digital, and transport infrastructure. Overall, the literature review provides strong evidence of infrastructure’s positive impact on employment, particularly for women. In the case of electricity, this impact arises from freeing time that would otherwise be spent on household tasks. Similarly, digital infrastructure, particularly mobile phone coverage, has demonstrated positive labor market effects, often driven by private sector investments rather than large public expenditures, which are typically required for other large-scale infrastructure projects. The evidence on structural transformation is also positive, with some notable exceptions, such as studies that find no significant impact on structural transformation in rural India in the cases of electricity and roads. Even with better market connections, remote areas may continue to lack economic opportunities, due to the absence of agglomeration economies and complementary inputs such as human capital. Accordingly, reducing transport costs alone may not be sufficient to drive economic transformation in rural areas. The spatial dimension of transformation is particularly relevant for transport, both internationally—by enhancing trade integration—and within countries, where economic development tends to drive firms and jobs toward urban centers, benefitting from economies scale and network effects. Turning to organizational transformation, evidence on skill bias in developing countries is more mixed than in developed countries and may vary considerably by context. Further research, especially on the possible reasons explaining the differences between developed and developing economies, is needed.
Journal
Journal Volume
Journal Issue

Related items

Showing items related by metadata.

  • Publication
    Robustness of Shared Prosperity Estimates
    (World Bank, Washington, DC, 2016-03) Wieser, Christina; Atamanov, Aziz; Uematsu, Hiroki; Yoshida, Nobuo; Nguyen, Minh Cong; Wagner De Azevedo, Joao Pedro; Dewina, Reno
    This paper is the first to systematically test the robustness of shared prosperity estimates to different methodological choices using a sample of countries from all regions in the world. The tests that are conducted include grouped versus microdata, nominal welfare aggregate versus adjustment for spatial price variation, and different treatment of income with negative and zero values. The empirical results reveal an only minimal impact of the proposed tests on shared prosperity estimates. Nevertheless, there are important caveats. First, spatial adjustment can change the ranking of households, affecting the distribution of the population in the bottom 40 percent. Second, the negligible impact of spatial deflation holds only if price adjustments are carried out consistently over time. Finally, the treatment of negative and zero income numbers can potentially lead to substantial differences in shared prosperity, depending on the magnitude of negative income and the share of households with negative and zero numbers across years.
  • Publication
    Pull Your Small Area Estimates Up by the Bootstraps
    (World Bank, Washington, DC, 2020-05) Molina, Isabel; Corral, Paul; Nguyen, Minh
    After almost two decades of poverty maps produced by the World Bank and multiple advances in the literature, this paper presents a methodological update to the World Bank's toolkit for small area estimation. The paper reviews the computational procedures of the current methods used by the World Bank: the traditional approach by Elbers, Lanjouw and Lanjouw (2003) and the Empirical Best/Bayes (EB) addition introduced by Van der Weide (2014). The addition extends the EB procedure of Molina and Rao (2010) by considering heteroscedasticity and includes survey weights, but uses a different bootstrap approach, here referred to as clustered bootstrap. Simulation experiments comparing these methods to the original EB approach of Molina and Rao (2010) provide empirical evidence of the shortcomings of the clustered bootstrap approach, which yields biased point estimates. The main contributions of this paper are then two: 1) to adapt the original Monte Carlo simulation procedure of Molina and Rao (2010) for the approximation of the extended EB estimators that include heteroscedasticity and survey weights as in Van der Weide (2014); and 2) to adapt the parametric bootstrap approach for mean squared error (MSE) estimation considered by Molina and Rao (2010), and proposed originally by González-Manteiga et al. (2008), to these extended EB estimators. Simulation experiments illustrate that the revised Monte Carlo simulation method yields estimators that are considerably less biased and more efficient in terms of MSE than those obtained from the clustered bootstrap approach, and that the parametric bootstrap MSE estimators are in line with the true MSEs under realistic scenarios.
  • Publication
    Pull Your Small Area Estimates Up by the Bootstraps
    (Taylor and Francis, 2021-05-08) Molina, Isabel; Corral, Paul; Nguyen, Minh
    This paper presents a methodological update to the World Bank's toolkit for small area estimation. The paper reviews the computational procedures of the current methods used by the institution: the traditional ELL approach and the Empirical Best (EB) addition introduced to imitate the original EB procedure of Molina and Rao [Small area estimation of poverty indicators. Canadian J Stat. 2010;38(3):369–385], including heteroskedasticity and survey weights, but using a different bootstrap approach, here referred to as clustered bootstrap. Simulation experiments provide empirical evidence of the shortcomings of the clustered bootstrap approach, which yields biased and noisier point estimates. The document presents an update to the World Bank’s EB implementation by considering the original EB procedures for point and noise estimation, extended for complex designs and heteroscedasticity. Simulation experiments illustrate that the revised methods yield considerably less biased and more efficient estimators than those obtained from the clustered bootstrap approach.
  • Publication
    Small Area Estimation of Non-Monetary Poverty with Geospatial Data
    (World Bank, Washington, DC, 2020-09) Masaki, Takaaki; Newhouse, David; Silwal, Ani Rudra; Bedada, Adane; Engstrom, Ryan
    This paper uses data from Sri Lanka and Tanzania to evaluate the benefits of combining household surveys with geographically comprehensive geospatial indicators to generate small area estimates of non-monetary poverty. The preferred estimates are generated by utilizing subarea-level geospatial indicators in a household-level empirical best predictor mixed model with a normalized welfare measure. Mean squared errors are estimated using a parametric bootstrap procedure. The resulting estimates are highly correlated with non-monetary poverty calculated from the full census in both countries, and the gain in precision is comparable to increasing the size of the sample by a factor of three in Sri Lanka and five in Tanzania. The empirical best predictor model moderately underestimates uncertainty, but coverage rates are similar to standard survey-based estimates that assume independent outcomes across clusters. A variety of checks, including adding noise to the welfare measure and model-based and design-based simulations, confirm that the main results are robust. The results demonstrate that combining household survey data with subarea-level geospatial indicators can greatly increase the precision of survey estimates of non-monetary poverty at comparatively low cost.
  • Publication
    Poverty, Inequality, and Agriculture in the EU
    (World Bank, Washington, DC, 2018-11) van den Brink, Rogier J. E.; Azevedo, Joao Pedro; Avila, Montserrat; Corral, Paul; Zhao, Hongxi; Mostafavi, Mohammad-Hadi
    Boosting convergence and shared prosperity in the European Union achieved renewed urgency after the global financial crisis of 2008. This paper assesses the role of agriculture and the Common Agricultural Program in achieving this. The paper sheds light on the relationship between poverty and agriculture as part of the process of structural transformation. It positions each member country on the path toward a successful structural transformation. The paper then evaluates at the regional level where the Common Agricultural Program funding tends to go, poverty-wise, within each country. This approach enables making more informed policy recommendations on the current state of the Common Agricultural Program funding, as well as evaluating the role of agriculture as a driver of shared prosperity. The analysis performed throughout the paper uses a combination of data sources at several spatial levels.

Users also downloaded

Showing related downloaded files

  • Publication
    Classroom Assessment to Support Foundational Literacy
    (Washington, DC: World Bank, 2025-03-21) Luna-Bazaldua, Diego; Levin, Victoria; Liberman, Julia; Gala, Priyal Mukesh
    This document focuses primarily on how classroom assessment activities can measure students’ literacy skills as they progress along a learning trajectory towards reading fluently and with comprehension by the end of primary school grades. The document addresses considerations regarding the design and implementation of early grade reading classroom assessment, provides examples of assessment activities from a variety of countries and contexts, and discusses the importance of incorporating classroom assessment practices into teacher training and professional development opportunities for teachers. The structure of the document is as follows. The first section presents definitions and addresses basic questions on classroom assessment. Section 2 covers the intersection between assessment and early grade reading by discussing how learning assessment can measure early grade reading skills following the reading learning trajectory. Section 3 compares some of the most common early grade literacy assessment tools with respect to the early grade reading skills and developmental phases. Section 4 of the document addresses teacher training considerations in developing, scoring, and using early grade reading assessment. Additional issues in assessing reading skills in the classroom and using assessment results to improve teaching and learning are reviewed in section 5. Throughout the document, country cases are presented to demonstrate how assessment activities can be implemented in the classroom in different contexts.
  • Publication
    The Journey Ahead
    (Washington, DC: World Bank, 2024-10-31) Bossavie, Laurent; Garrote Sánchez, Daniel; Makovec, Mattia
    The Journey Ahead: Supporting Successful Migration in Europe and Central Asia provides an in-depth analysis of international migration in Europe and Central Asia (ECA) and the implications for policy making. By identifying challenges and opportunities associated with migration in the region, it aims to inform a more nuanced, evidencebased debate on the costs and benefits of cross-border mobility. Using data-driven insights and new analysis, the report shows that migration has been an engine of prosperity and has helped address some of ECA’s demographic and socioeconomic disparities. Yet, migration’s full economic potential remains untapped. The report identifies multiple barriers keeping migration from achieving its full potential. Crucially, it argues that policies in both origin and destination countries can help maximize the development impacts of migration and effectively manage the economic, social, and political costs. Drawing from a wide range of literature, country experiences, and novel analysis, The Journey Ahead presents actionable policy options to enhance the benefits of migration for destination and origin countries and migrants themselves. Some measures can be taken unilaterally by countries, whereas others require close bilateral or regional coordination. The recommendations are tailored to different types of migration— forced displacement as well as high-skilled and low-skilled economic migration—and from the perspectives of both sending and receiving countries. This report serves as a comprehensive resource for governments, development partners, and other stakeholders throughout Europe and Central Asia, where the richness and diversity of migration experiences provide valuable insights for policy makers in other regions of the world.
  • Publication
    World Development Report 2006
    (Washington, DC, 2005) World Bank
    This year’s Word Development Report (WDR), the twenty-eighth, looks at the role of equity in the development process. It defines equity in terms of two basic principles. The first is equal opportunities: that a person’s chances in life should be determined by his or her talents and efforts, rather than by pre-determined circumstances such as race, gender, social or family background. The second principle is the avoidance of extreme deprivation in outcomes, particularly in health, education and consumption levels. This principle thus includes the objective of poverty reduction. The report’s main message is that, in the long run, the pursuit of equity and the pursuit of economic prosperity are complementary. In addition to detailed chapters exploring these and related issues, the Report contains selected data from the World Development Indicators 2005‹an appendix of economic and social data for over 200 countries. This Report offers practical insights for policymakers, executives, scholars, and all those with an interest in economic development.
  • Publication
    Lebanon Economic Monitor, Fall 2022
    (Washington, DC, 2022-11) World Bank
    The economy continues to contract, albeit at a somewhat slower pace. Public finances improved in 2021, but only because spending collapsed faster than revenue generation. Testament to the continued atrophy of Lebanon’s economy, the Lebanese Pound continues to depreciate sharply. The sharp deterioration in the currency continues to drive surging inflation, in triple digits since July 2020, impacting the poor and vulnerable the most. An unprecedented institutional vacuum will likely further delay any agreement on crisis resolution and much needed reforms; this includes prior actions as part of the April 2022 International Monetary Fund (IMF) staff-level agreement (SLA). Divergent views among key stakeholders on how to distribute the financial losses remains the main bottleneck for reaching an agreement on a comprehensive reform agenda. Lebanon needs to urgently adopt a domestic, equitable, and comprehensive solution that is predicated on: (i) addressing upfront the balance sheet impairments, (ii) restoring liquidity, and (iii) adhering to sound global practices of bail-in solutions based on a hierarchy of creditors (starting with banks’ shareholders) that protects small depositors.
  • Publication
    Argentina Country Climate and Development Report
    (World Bank, Washington, DC, 2022-11) World Bank Group
    The Argentina Country Climate and Development Report (CCDR) explores opportunities and identifies trade-offs for aligning Argentina’s growth and poverty reduction policies with its commitments on, and its ability to withstand, climate change. It assesses how the country can: reduce its vulnerability to climate shocks through targeted public and private investments and adequation of social protection. The report also shows how Argentina can seize the benefits of a global decarbonization path to sustain a more robust economic growth through further development of Argentina’s potential for renewable energy, energy efficiency actions, the lithium value chain, as well as climate-smart agriculture (and land use) options. Given Argentina’s context, this CCDR focuses on win-win policies and investments, which have large co-benefits or can contribute to raising the country’s growth while helping to adapt the economy, also considering how human capital actions can accompany a just transition.