Essama-Nssah, Boniface

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Essama-Nssah, Boniface

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Essama-Nssah, B.

Fields of Specialization

Poverty and growth, Program evaluation, Social impact of public policy

Last updated: January 31, 2023

Biography

B. Essama-Nssah worked for 17 years for the World Bank in Washington, DC, before he retired as a senior economist in 2011. During his tenure at the Bank, he performed economic analyses, prepared policy research and technical papers, and conducted an annual training course on impact evaluation methodologies for staff from the World Bank and client countries. Before joining the World Bank, Essama-Nssah worked for two years as a senior research associate on the Food and Nutrition Program at Cornell University, and for six years as head of the Economics Department and vice dean of the Faculty of Law and Economics of the University of Yaoundé, Cameroon. He currently works as a consultant focusing on poverty and growth incidence analysis, program evaluation, and analysis of the social impact of public policy. He holds a PhD in economics from the University of Michigan in Ann Arbor.

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Now showing 1 - 10 of 20

Counterfactual Decomposition of Pro-Poorness Using Influence Functions
(Taylor and Francis, 2015-12-11) Lambert, Peter J.; Essama-Nssah, B.
Poverty reduction has emerged as a fundamental social objective of development, and has become a metric commonly used to assess the performance of public policy. This paper adapts the methodology of Firpo, Fortin and Lemieux (2009) [2009. “Unconditional Quantile Regressions.” Econometrica 77 (3): 953–973] to the measurement of the pro-poorness of income growth. The method allows the analyst to identify co-variates that affect poverty reduction. The methodology is policy-relevant because policy-makers can better target these co-variates than the average level of income, or the level of inequality. We demonstrate this by application to Bangladesh 2000–2010.
Understanding Changes in Poverty
(World Bank Group, Washington, DC, 2014-08-12) Van Nguyen, Trang; Inchauste, Gabriela; Azevedo, João Pedro; Essama-Nssah, B.; Olivieri, Sergio; Saavedra-Chanduvi, Jaime; Winkler, Hernan
Understanding Changes in Poverty brings together different methods to decompose the contributions to poverty reduction. A simple approach quantifies the contribution of changes in demographics, employment, earnings, public transfers, and remittances to poverty reduction. A more complex approach quantifies the contributions to poverty reduction from changes in individual and household characteristics, including changes in the sectoral, occupational, and educational structure of the workforce, as well as changes in the returns to individual and household characteristics. Understanding Changes in Poverty implements these approaches and finds that labor income growth that is, growth in income per worker rather than an increase in the number of employed workers was the largest contributor to moderate poverty reduction in 21 countries experiencing substantial reductions in poverty over the past decade. Changes in demographics, public transfers, and remittances helped, but made relatively smaller contributions to poverty reduction. Further decompositions in three countries find that labor income grew mainly because of higher returns to human capital endowments, signaling increases in productivity, higher relative price of labor, or both. Understanding Changes in Poverty will be of particular relevance to development practitioners interested in better understanding distributional changes over time. The methods and tools presented in this book can also be applied to better understand changes in inequality or any other distributional change.
Too Little Too Late : Welfare Impacts of Rainfall Shocks in Rural Indonesia
(Taylor and Francis, 2012-11-20) Katayama, Roy S.; Skoufias, Emmanuel; Essama-Nssah, B.
We use regression analysis to assess the potential welfare impacts in rural Indonesia of two types of shock: a delay in monsoon onset; and a significant shortfall in rain during the 90-day post-onset period. Focusing on households with family farm businesses, we find that a delay in monsoon onset does not have a significant effect on the welfare of rice farmers. However, rice farm households located in areas exposed to low rainfall following the monsoon are negatively affected. Such households appear to be able to protect their food expenditure in the face of weather shocks, but at the expense of their non-food expenditure. We also use propensity score matching to identify community programs that might moderate the impact of this type of shock. We find that access to credit and public works projects has the strongest moderating effect. This is an important consideration for the design and implementation of adaptation strategies.
Identification of Sources of Variation in Poverty Outcomes
(2012-01-01) Essama-Nssah, B.
The international community has declared poverty reduction one of the fundamental objectives of development, and therefore a metric for assessing the effectiveness of development interventions. This creates the need for a sound understanding of the fundamental factors that account for observed variations in poverty outcomes either over time or across space. Consistent with the view that such an understanding entails deeper micro empirical work on growth and distributional change, this paper reviews existing decomposition methods that can be used to identify sources of variation in poverty. The maintained hypothesis is that the living standard of an individual is a pay-off from her participation in the life of society. In that sense, individual outcomes depend on endowments, behavior and the circumstances that determine the returns to those endowments in any social transaction. To identify the contribution of each of these factors to changes in poverty, the statistical and structural methods reviewed in this paper all rely on the notion of ceteris paribus variation. This entails the comparison of an observed outcome distribution to a counterfactual obtained by changing one factor at a time while holding all the other factors constant.
Too Little Too Late : Welfare Impacts of Rainfall Shocks in Rural Indonesia
(2011-03-01) Katayama, Roy S.; Skoufias, Emmanuel; Essama-Nssah, B.
The authors use regression analysis to assess the potential welfare impact of rainfall shocks in rural Indonesia. In particular, they consider two shocks: (i) a delay in the onset of monsoon and (ii) a significant shortfall in the amount of rain in the 90 day post-onset period. Focusing on households with family farm businesses, the analysis finds that a delay in the monsoon onset does not have a significant impact on the welfare of rice farmers. However, rice farm households located in areas exposed to low rainfall following the monsoon are negatively affected. Rice farm households appear to be able to protect their food expenditure in the face of weather shocks at the expense of lower nonfood expenditures per capita. The authors use propensity score matching to identify community programs that might moderate the welfare impact of this type of shock. Access to credit and public works projects in communities were among the programs with the strongest moderating effects. This is an important consideration for the design and implementation of adaptation strategies.
A Counterfactual Analysis of the Poverty Impact of Economic Growth in Cameroon
(2010-03-01) Bassole, Leandre; Essama-Nssah, B.
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.
Accounting for Heterogeneity in Growth Incidence in Cameroon
(2010-11-01) Bassole, Leandre; Essama-Nssah, B.; Paul, Saumik
This paper presents counterfactual decompositions based on both the Shapley method and a generalization of the Oaxaca-Blinder approach to identify proximate factors that might explain differences in the distribution of economic welfare in Cameroon in 1996-2007. In particular, the analysis uses re-centered influence function regressions to link the growth incidence curve for 2001-2007 to household characteristics and account for heterogeneity of impact across quantiles in terms of the composition (or endowment) effect and structural (or price) effect. The analysis finds that the level of the growth incidence curve is explained by the endowment effect while its shape is driven by the price effect. Observed gains at the bottom of the distribution are due to returns to endowments. The rest of the gains are accounted for by the composition effect. Further decomposition of these effects shows that the composition effect is determined mainly by household demographics while the structural effect is shaped by the sector of employment and geography. Finally, analysis of the rural-urban gap in living standards shows that, for the poorest households in both sectors, differences in household characteristics matter more than the returns to those characteristics. The opposite is true for better-off households.
Assessing the Redistributive Effect of Fiscal Policy
(World Bank, Washington, DC, 2008-04) Essama-Nssah, B.
Who benefits from public spending? Who bears the burden of taxation? How desirable is the distribution of net benefits from the operation of a tax-benefit system? This paper surveys basic concepts, methods, and modeling approaches commonly used to address these issues in the context of fiscal incidence analysis. The review covers the incidence of both taxation and public spending. Methodological points are supported by country cases. The effective distribution of benefits and burdens associated with fiscal policy depends on the size of the government, the distributive mechanisms involved, and the incentives properties of the policy under consideration. This creates a need for analytical methods to account for both individual behavior and social interaction. The approaches reviewed include simple reduced form regression analysis, microsimulation models (both the envelope and discrete choice models), computable general equilibrium modeling, and approaches that link computable general equilibrium models to microsimulation models. Explicit modeling facilitates the construction of counterfactuals to back up causal analysis. Social desirability is assessed on the basis of progressivity along with deadweight loss.
A Poverty-Focused Evaluation of Commodity Tax Options
(World Bank, Washington, DC, 2007-06) Essama-Nssah, B.
The difficulties faced by many developing countries in raising revenue from direct taxes have forced them to rely heavily on indirect taxes to finance development interventions. The purpose of this paper is to show how to identify socially desirable options for commodity taxation in the context of a poverty reduction strategy. Within the logic of social evaluation the author assesses tax options on the basis of value judgments underlying members of the additively separable class of poverty measures. The criterion hinges on both the pattern of consumption of each commodity and the price elasticity of the poverty measure used. An application of this methodology to data for Guinea shows that many components of food expenditure (particularly cereals, grains, and roots) would be good candidates for exemption from value-added tax. Even though expenditure on health and education is distributed in favor of the non-poor, their importance for human capital development argues for a program of targeted subsidies in a broader context of cost recovery.
Propensity Score Matching and Policy Impact Analysis : A Demonstration in EViews
(World Bank, Washington, DC, 2006-04) Essama-Nssah, B.
Effective development policymaking creates a need for reliable methods of assessing effectiveness. There should be, therefore, an intimate relationship between effective policymaking and impact analysis. The goal of a development intervention defines the metric by which to assess its impact, while impact evaluation can produce reliable information on which policymakers may base decisions to modify or cancel ineffective programs and thus make the most of limited resources. This paper reviews the logic of propensity score matching (PSM) and, using data on the National Support Work Demonstration, compares that approach with other evaluation methods such as double difference, instrumental variable, and Heckman's method of selection bias correction. In addition, it demonstrates how to implement nearest-neighbor and kernel-based methods, and plot program incidence curves in E-Views. In the end, the plausibility of an evaluation method hinges critically on the correctness of the socioeconomic model underlying program design and implementation, and on the quality and quantity of available data. In any case, PSM can act as an effective adjuvant to other methods.