Kraay, Aart

Development Research Group, The World Bank
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Macroeconomics, Debt management, Economic growth, Inequality and shared prosperity
Development Research Group, The World Bank
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Last updated: January 31, 2023
Aart Kraay is Director of Research in the Development Research Group at the World Bank. He joined the World Bank in 1995 after earning a Ph.D. in economics from Harvard University (1995), and a B.Sc. in economics from the University of Toronto (1990). His research interests include international capital movements, growth and inequality, governance, and the Chinese economy. His research on these topics has been published in scholarly journals such as the Quarterly Journal of Economics, the Review of Economics and Statistics, the Economic Journal, the Journal of Monetary Economics, the Journal of International Economics, and the Journal of the European Economic Association. He is an associate editor of the Journal of Development Economics, and co-editor of the World Bank Economic Review. He has also held visiting positions at the International Monetary Fund and the Sloan School of Management at MIT, and has taught at the School of Advanced International Studies at Johns Hopkins University.
Citations 714 Scopus

Publication Search Results

Now showing 1 - 10 of 20
  • Publication
    Growth Still Is Good for the Poor
    (World Bank, Washington, DC, 2013-08) Dollar, David; Kleineberg, Tatjana; Kraay, Aart
    Incomes in the poorest two quintiles on average increase at the same rate as overall average incomes. This is because, in a global dataset spanning 118 countries over the past four decades, changes in the share of income of the poorest quintiles are generally small and uncorrelated with changes in average income. The variation in changes in quintile shares is also small relative to the variation in growth in average incomes, implying that the latter accounts for most of the variation in income growth in the poorest quintiles. These findings hold across most regions and time periods and when conditioning on a variety of country-level factors that may matter for growth and inequality changes. This evidence confirms the central importance of economic growth for poverty reduction and illustrates the difficulty of identifying specific macroeconomic policies that are significantly associated with the relative growth rates of those in the poorest quintiles.
  • Publication
    Fiscal Policy as a Tool for Stabilization in Developing Countries
    (World Bank, Washington, DC, 2013-02) Kraay, Aart; Serven, Luis
    The financial crisis of 2007/2008, the subsequent great recession in rich countries and its propagation to developing countries has sparked a renewed interest in the role of fiscal policy as a potential countercyclical tool among policymakers and researchers. This paper reviews the state of empirical evidence on the effectiveness of discretionary countercyclical fiscal policy by placing a particular emphasis on developing countries. On the whole, successful fiscal interventions of this type have been rare in the developing world. This note also briefly reviews contrasting experiences of success and failure in industrial and developing countries. It concludes with several recommendations motivated by past experiences policymakers should consider before adopting any fiscal responses to the current crisis.
  • Publication
    Good Countries or Good Projects? Macro and Micro Correlates of World Bank Project Performance
    (Elsevier, 2013-07-13) Denizer, Cevdet; Kaufmann, Daniel; Kraay, Aart
    This paper investigates macro and micro correlates of aid-financed development project outcomes, using data from over 6000 World Bank projects evaluated between 1983 and 2011. Country-level “macro” measures of the quality of policies and institutions are strongly correlated with project outcomes, consistent with the view that country-level performance matters for aid effectiveness. However, a striking feature of the data is that the success of individual development projects varies much more within countries than it does between countries. A large set of project-level “micro” variables, including project size, project length, the effort devoted to project preparation and supervision, and early-warning indicators that flag problematic projects during the implementation stage, accounts for some of this within-country variation in project outcomes. Measures of World Bank project manager quality also matter significantly for the ultimate project outcomes. We discuss the implications of these findings for donor policies aimed at aid effectiveness.
  • Publication
    Approximating Income Distribution Dynamics Using Aggregate Data
    (World Bank, Washington, DC, 2017-06) Kraay, Aart; Van der Weide, Roy
    This paper proposes a methodology to approximate individual income distribution dynamics using only time series data on aggregate moments of the income distribution. Under the assumption that individual incomes follow a lognormal autoregressive process, this paper shows that the evolution over time of the mean and standard deviation of log income across individuals provides sufficient information to place upper and lower bounds on the degree of mobility in the income distribution. The paper demonstrates that these bounds are reasonably informative, using the U.S. Panel Study of Income Dynamics where the panel structure of the data allows us to compare measures of mobility directly estimated from the micro data with approximations based only on aggregate data. Bounds on mobility are estimated for a large cross-section of countries, using data on aggregate moments of the income distribution available in the World Wealth and Income Database and the World Bank's PovcalNet database. The estimated bounds on mobility imply that conventional anonymous growth rates of the bottom 40 percent (top 10 percent) that do not account for mobility substantially understate (overstate) the expected growth performance of those initially in the bottom 40 percent (top 10 percent).
  • Publication
    "Crowding in" and the Returns to Government Investment in Low-Income Countries
    (World Bank, Washington, DC, 2014-02) Eden, Maya; Kraay, Aart
    This paper estimates the effect of government investment on private investment in a sample of 39 low-income countries. Fluctuations in a predetermined component of disbursements on loans from official creditors to developing country governments are used as an instrument for fluctuations in public investment. The analysis finds evidence of "crowding in": an extra dollar of government investment raises private investment by roughly two dollars, and output by 1.5 dollars. To understand the implications for the return to public investment, a CES production function with public and private capital as inputs is calibrated. For most countries in the sample, the returns to government investment exceed the world interest rate. However, for some countries that already have high government investment rates, the return to further investment is below the world interest rate.
  • Publication
    Weak Instruments in Growth Regressions: Implications for Recent Cross-Country Evidence on Inequality and Growth
    (World Health Organization, 2015-11) Kraay, Aart
    This paper revisits four recent cross-country empirical studies on the effects of inequality on growth. All four studies report strongly significant negative effects, using the popular system generalized method of moments estimator that is frequently used in cross-country growth empirics. This paper shows that the internal instruments relied on by this estimator in these inequality-and-growth regressions are weak, and that weak instrument-consistent confidence sets for the effect of inequality on growth include a wide range of positive and negative values. This suggests that strong conclusions about the effect of inequality on growth— in either direction—cannot be drawn from these studies. This paper also systematically explores a wide range of alternative sets of internal instruments, and finds that problems of weak instruments are pervasive across these alternatives. More generally, the paper illustrates the importance of documenting instrument strength, basing inferences on procedures that are robust to weak instruments, and considering alternative instrument sets when using the system generalized method of moments estimator for cross-country growth empirics.
  • Publication
    Growth, Inequality, and Social Welfare : Cross-Country Evidence
    (World Bank, Washington, DC, 2014-04) Dollar, David; Kleineberg, Tatjana; Kraay, Aart
    Social welfare functions that assign weights to individuals based on their income levels can be used to document the relative importance of growth and inequality changes for changes in social welfare. In a large panel of industrial and developing countries over the past 40 years, most of the cross-country and over-time variation in changes in social welfare is due to changes in average incomes. In contrast, the changes in inequality observed during this period are on average much smaller than changes in average incomes, are uncorrelated with changes in average incomes, and have contributed relatively little to changes in social welfare.
  • Publication
    Do Poverty Traps Exist?
    (World Bank, Washington, DC, 2014-04) Kraay, Aart; McKenzie, David
    This paper reviews the empirical evidence on the existence of poverty traps, understood as self-reinforcing mechanisms through which poor individuals or countries remain poor. Poverty traps have captured the interest of many development policy makers, because poverty traps provide a theoretically coherent explanation for persistent poverty. They also suggest that temporary policy interventions may have long-term effects on poverty. However, a review of the reduced-form empirical evidence suggests that truly stagnant incomes of the sort predicted by standard models of poverty traps are in fact quite rare. Moreover, the empirical evidence regarding several canonical mechanisms underlying models of poverty traps is mixed.
  • Publication
    Predicting Conflict
    (World Bank, Washington, DC, 2017-05) Celiku, Bledi; Kraay, Aart
    This paper studies the performance of alternative prediction models for conflict. The analysis contrasts the performance of conventional approaches based on predicted probabilities generated by binary response regressions and random forests with two unconventional classification algorithms. The unconventional algorithms are calibrated specifically to minimize a prediction loss function penalizing Type 1 and Type 2 errors: (1) an algorithm that selects linear combinations of correlates of conflict to minimize the prediction loss function, and (2) an algorithm that chooses a set of thresholds for the same variables, together with the number of breaches of thresholds that constitute a prediction of conflict, that minimize the prediction loss function. The paper evaluates the predictive power of these approaches in a set of conflict and non-conflict episodes constructed from a large country-year panel of developing countries since 1977, and finds substantial differences in the in-sample and out-of-sample predictive performance of these alternative algorithms. The threshold classifier has the best overall predictive performance, and moreover has advantages in simplicity and transparency that make it well suited for policy-making purposes. The paper explores the implications of these findings for the World Bank's classification of fragile and conflict-affected states.
  • Publication
    Predicting World Bank Project Outcome Ratings
    (World Bank Group, Washington, DC, 2014-08-01) Geli, Patricia; Kraay, Aart; Nobakht, Hoveida
    A number of recent studies have empirically documented links between characteristics of World Bank projects and their ultimate outcomes as evaluated by the World Bank's Independent Evaluation Group. This paper explores the in-sample and out-of-sample predictive performance of empirical models relating project outcomes to project characteristics observed early in the life of a project. Such models perform better than self-assessments of project performance provided by World Bank staff during the implementation of the project. These findings are applied to the problem of predicting eventual Independent Evaluation Group ratings for currently active projects in the World Bank's portfolio.