Publication: Exploring the Sources of Downward Bias in Measuring Inequality of Opportunity
Loading...
Published
2015-10
ISSN
Date
2015-11-05
Author(s)
Editor(s)
Abstract
This study analyzes the extent of downward bias in the calculation of inequality of opportunity for continuous outcomes such as income. A typically recognized source of bias is the unobserved circumstances as there is a limited set of variables available in household and labor force surveys. Another previously overlooked source is the likely unobservable nature of top incomes. Using Monte Carlo simulations where the underlying inequality of opportunity is predetermined at various levels, the study presents three key findings. First, the omission of a relevant circumstance can bias the inequality of opportunity estimate by as much as 80 percent, depending on how much variation of the outcome such circumstance explains. Second, not observing the top 5 percent of the income distribution can lead to downward biases of anywhere between 12 and 35 percent, and the combination of missing the most favored population and even one relevant circumstance exacerbates the bias of the empirical estimates. The third key result is that the estimated inequality of opportunity is strongly correlated with the amount of variation in the outcome variable explained by the combination of circumstances (measured by the R2). This result suggests that in empirical applications, the inequality of opportunity estimate can be roughly (and quickly) approximated using simple econometric techniques.
Link to Data Set
Citation
“Lara Ibarra, Gabriel; Martinez Cruz, Adan L.. 2015. Exploring the Sources of Downward Bias in Measuring Inequality of Opportunity. Policy Research Working Paper;No. 7458. © World Bank. http://hdl.handle.net/10986/22881 License: CC BY 3.0 IGO.”
Associated URLs
Associated content
Other publications in this report series
Publication Global Poverty Revisited Using 2021 PPPs and New Data on Consumption(Washington, DC: World Bank, 2025-06-05)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 The Economic Value of Weather Forecasts: A Quantitative Systematic Literature Review(Washington, DC: World Bank, 2025-09-10)This study systematically reviews the literature that quantifies the economic benefits of weather observations and forecasts in four weather-dependent economic sectors: agriculture, energy, transport, and disaster-risk management. The review covers 175 peer-reviewed journal articles and 15 policy reports. Findings show that the literature is concentrated in high-income countries and most studies use theoretical models, followed by observational and then experimental research designs. Forecast horizons studied, meteorological variables and services, and monetization techniques vary markedly by sector. Estimated benefits even within specific subsectors span several orders of magnitude and broad uncertainty ranges. An econometric meta-analysis suggests that theoretical studies and studies in richer countries tend to report significantly larger values. Barriers that hinder value realization are identified on both the provider and user sides, with inadequate relevance, weak dissemination, and limited ability to act recurring across sectors. Policy reports rely heavily on back-of-the-envelope or recursive benefit-transfer estimates, rather than on the methods and results of the peer-reviewed literature, revealing a science-to-policy gap. These findings suggest substantial socioeconomic potential of hydrometeorological services around the world, but also knowledge gaps that require more valuation studies focusing on low- and middle-income countries, addressing provider- and user-side barriers and employing rigorous empirical valuation methods to complement and validate theoretical models.Publication The Marshall Plan: Then and Now(Washington, DC: World Bank, 2025-10-14)This paper is a product of the Development Policy Team, Development Economics. It is part of a larger effort by the World Bank to provide open access to its research and make a contribution to development policy discussions around the world. Policy Research Working Papers are also posted on the Web at http://www.worldbank.org/prwp.Publication The Macroeconomic Implications of Climate Change Impacts and Adaptation Options(Washington, DC: World Bank, 2025-05-29)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 Geopolitical Risks and Trade(Washington, DC: World Bank, 2025-09-23)This paper studies the impact of geopolitical risks on international trade, using the Geopolitical Risk (GPR) index of Caldara and Iacoviello (2022) and an empirical gravity model. The impact of spikes in geopolitical risk on trade is negative, strong, and heterogeneous across sectors. The findings show that increases in geopolitical risk reduce trade by about 30 to 40 percent. These effects are equivalent to an increase of global tariffs of up to 14 percent. Services trade is most vulnerable to geopolitical risks, followed by agriculture, and the impact on manufacturing trade is moderate. These negative effects are partially mitigated by cultural and geographic proximity, as well as by the presence of trade agreements.
Journal
Journal Volume
Journal Issue
Collections
Related items
Showing items related by metadata.
Publication A Counterfactual Analysis of the Poverty Impact of Economic Growth in Cameroon(2010-03-01)The Government of Cameroon has declared poverty reduction through strong and sustainable economic growth the central objective of its socioeconomic policy. This paper uses available household survey data to assess the performance of the economy with respect to this objective over the period 1996-2007. The authors use counterfactual decompositions based on both the Shapley method and the generalized Oaxaca-Blinder framework to identify proximate factors that might explain differences in observed outcomes over time, across regions and households. The concept of pro-poorness provides a basis for a normative evaluation of these outcomes. The analysis of changes in the size distribution of economic welfare reveals that formal sector employment, access to credit, education, and urban residence are characteristics that bring significantly high returns to households. Employment in smallholder agriculture has a negative impact on welfare across quantiles. Economic growth was accompanied by significant poverty reduction between 1996 and 2001. But poverty barely decreased between 2001 and 2007 due to very weak growth. Over the same period, household investment in human capital took a serious hit. Given the additional finding that the pattern of growth is characterized by urban bias and regional disparity, the overall assessment is that economic growth has been weakly pro-poor in Cameroon. There is therefore a need to re-examine and possibly reform the mechanisms governing the allocation of public resources designed to support individuals' efforts to improve their standard of living.Publication The Measurement of Inequality of Opportunity : Theory and an Application to Latin America(World Bank, Washington, DC, 2008-07)What part of the inequality observed in a particular country is due to unequal opportunities, rather than to differences in individual efforts or luck? This paper estimates a lower bound for the opportunity share of inequality in labor earnings, household income per capita and household consumption per capita in six Latin American countries. Following John Roemer, the authors associate inequality of opportunity with outcome differences that can be accounted for by morally irrelevant pre-determined circumstances, such as race, gender, place of birth, and family background. Thus defined, unequal opportunities account for between 24 and 50 percent of inequality in consumption expenditure in the sample. Brazil and Central America are more opportunity-unequal than Colombia, Ecuador, or Peru. "Opportunity profiles," which identify the social groups with the most limited opportunity sets, are shown to be distinct from poverty profiles: ethnic origin and the geography of birth are markedly more important as determinants of opportunity deprivation than of outcome poverty, particularly in Brazil, Guatemala, and Peru.Publication Finance, Inequality, and Poverty: Cross-Country Evidence(World Bank, Washington, DC, 2004-06)While substantial research finds that financial development boosts overall economic growth, the authors study whether financial development is pro-poor: Does financial development disproportionately raise the income of the poor? Using a broad cross-country sample, the authors find that the answer is yes: Financial intermediary development reduces income inequality by disproportionately boosting the income of the poor and therefore reduces poverty. This result is robust to controlling for simultaneity bias and reverse causation.Publication A Micro-Decomposition Analysis of the Macroeconomic Determinants of Human Development(World Bank, Washington, DC, 2007-09)This paper shows how differences in aggregate human development outcomes over time and space can be additively decomposed into a pure economic-growth component, a component attributed to differences in the distribution of income, and components attributed to "non-income" factors and differences in the model linking outcomes to income or non-income characteristics. The income effect at the micro level is modeled non-parametrically, so as to flexibly reflect distributional changes. The paper illustrates the decomposition using data for Morocco and Vietnam, and the results offer some surprising insights into the observed aggregate gains in schooling attainments. A user friendly STATA program is available to implement the method in other settings.Publication Inequality of Opportunity, Income Inequality and Economic Mobility : Some International Comparisons(World Bank, Washington, DC, 2013-01)Despite a recent surge in the number of studies attempting to measure inequality of opportunity in various countries, methodological differences have so far prevented meaningful international comparisons. This paper presents a comparison of ex-ante measures of inequality of economic opportunity (IEO) across 41 countries, and of the Human Opportunity Index (HOI) for 39 countries. It also examines international correlations between these indices and output per capita, income inequality, and intergenerational mobility. The analysis finds evidence of a "Kuznets curve" for inequality of opportunity, and finds that the IEO index is positively correlated with overall income inequality, and negatively with measures of intergenerational mobility, both in incomes and in years of schooling. The HOI is highly correlated with the Human Development Index, and its internal measure of inequality of opportunity yields very different country rankings from the IEO measure.
Users also downloaded
Showing related downloaded files
Publication Classroom Assessment to Support Foundational Literacy(Washington, DC: World Bank, 2025-03-21)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 World Development Report 2006(Washington, DC, 2005)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 Morocco Economic Update, Winter 2025(Washington, DC: World Bank, 2025-04-03)Despite the drought causing a modest deceleration of overall GDP growth to 3.2 percent, the Moroccan economy has exhibited some encouraging trends in 2024. Non-agricultural growth has accelerated to an estimated 3.8 percent, driven by a revitalized industrial sector and a rebound in gross capital formation. Inflation has dropped below 1 percent, allowing Bank al-Maghrib to begin easing its monetary policy. While rural labor markets remain depressed, the economy has added close to 162,000 jobs in urban areas. Morocco’s external position remains strong overall, with a moderate current account deficit largely financed by growing foreign direct investment inflows, underpinned by solid investor confidence indicators. Despite significant spending pressures, the debt-to-GDP ratio is slowly declining.Publication Argentina Country Climate and Development Report(World Bank, Washington, DC, 2022-11)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.Publication Digital Africa(Washington, DC: World Bank, 2023-03-13)All African countries need better and more jobs for their growing populations. "Digital Africa: Technological Transformation for Jobs" shows that broader use of productivity-enhancing, digital technologies by enterprises and households is imperative to generate such jobs, including for lower-skilled people. At the same time, it can support not only countries’ short-term objective of postpandemic economic recovery but also their vision of economic transformation with more inclusive growth. These outcomes are not automatic, however. Mobile internet availability has increased throughout the continent in recent years, but Africa’s uptake gap is the highest in the world. Areas with at least 3G mobile internet service now cover 84 percent of Africa’s population, but only 22 percent uses such services. And the average African business lags in the use of smartphones and computers as well as more sophisticated digital technologies that catalyze further productivity gains. Two issues explain the usage gap: affordability of these new technologies and willingness to use them. For the 40 percent of Africans below the extreme poverty line, mobile data plans alone would cost one-third of their incomes—in addition to the price of access devices, apps, and electricity. Data plans for small- and medium-size businesses are also more expensive than in other regions. Moreover, shortcomings in the quality of internet services—and in the supply of attractive, skills-appropriate apps that promote entrepreneurship and raise earnings—dampen people’s willingness to use them. For those countries already using these technologies, the development payoffs are significant. New empirical studies for this report add to the rapidly growing evidence that mobile internet availability directly raises enterprise productivity, increases jobs, and reduces poverty throughout Africa. To realize these and other benefits more widely, Africa’s countries must implement complementary and mutually reinforcing policies to strengthen both consumers’ ability to pay and willingness to use digital technologies. These interventions must prioritize productive use to generate large numbers of inclusive jobs in a region poised to benefit from a massive, youthful workforce—one projected to become the world’s largest by the end of this century.