nep-afr New Economics Papers
on Africa
Issue of 2009‒12‒11
twenty-two papers chosen by
Quentin Wodon
World Bank

  1. Controlling cassava mosaic virus and cassava mealybug in Sub-Saharan Africa: By Nweke, Felix
  2. Food and nutrition emergencies in East Africa: Political, economic and environmental associations By Oniang'o, Ruth
  3. Does Land Abundance Explain African Institutions? By Fenske, James
  4. Private sector responses to public investments and policy reforms: The case of fertilizer and maize market development in Kenya By Ariga, Joshua; Jayne, Thomas S.
  5. Determinants of Household Fuel Choice in Major Cities in Ethiopia By Mekonnen, Alemu; Köhlin, Gunnar
  6. Does Human Capital Protect Workers against Exogenous Shocks? South Africa in the 2008-2009 Crisis By Leung, Ron; Stampini, Marco; Vencatachellum, Désiré
  7. Economics of Soil Conservation Adoption in High-Rainfall Areas of the Ethiopian Highlands By Kassie, Menale; Holden, Stein; Köhlin, Gunnar; Bluffstone, Randy
  8. How Do Ethnic Militias Perpetuate in Nigeria? A Micro-level Perspective on the Oodua People’s Congress By Yvan Guichaoua
  9. The Production of Insecurity by African Security Forces: Insights from Liberia and the Central African Republic By Andreas Mehler
  10. Lower Partial Moments as a measure of vulnerability to poverty in Cameroon By Witt, Rudolf; Waibel, Hermann
  11. Brainy Africans to Fortress Europe: For Money or Colonial Vestiges? By Constant, Amelie F.; Tien, Bienvenue
  12. The Role of Soil Conservation on Mean Crop Yield and Variance of Yield - Evidence from the Ethiopian Highlands By Kassie, Menale; Pender, John; Yesuf, Mahmud; Köhlin, Gunnar; Mulugeta, Elias
  13. Institutional reform in the Burkinabè cotton sector and its impacts on incomes and food security: 1996-2006 By Kaminski, Jonathan; Headey, Derek; Bernard, Tanguy
  14. The Role of Production Risk in Sustainable Land-Management Technology Adoption in the Ethiopian Highlands By Kassie, Menale; Yesuf, Mahmud; Köhlin, Gunnar
  15. Border Price Shocks, Spatial Price Variation, and their Impacts on Poverty in Uganda By Ole Boysen
  16. Market Imperfections and Farm Technology Adoption Decisions - A Case Study from the Highlands of Ethiopia By Yesuf, Mahmud; Köhlin, Gunnar
  17. Soil Conservation and Small-Scale Food Production in Highland Ethiopia A Stochastic Metafrontier Approach By Medhin, Haileselassie A.; Köhlin, Gunnar
  18. The Economic Partnership Agreement between Uganda and the EU: Trade and Poverty Impacts By Ole Boysen; Alan Matthews
  19. Estimating Returns to Soil and Water Conservation Investments - An Application to Crop Yield in Kenya By Nyangena, Wilfred; Köhlin, Gunnar
  20. Risk Implications of Farm Technology Adoption in the Ethiopian Highlands By Yesuf, Mahmud; Kassie, Menale; Köhlin, Gunnar
  21. Agricultural Risk Management through Community-Based Wildlife Conservation in Rural Zimbabwe By Muchapondwa, Edwin; Sterner, Thomas
  22. Agroenvironmental transformation in the Sahel: Another kind of “Green Revolution" By Reij, Chris; Tappan, Gary; Smale, Melinda

  1. By: Nweke, Felix
    Keywords: millions fed, Cassava, mosaic virus, mealybug,
    Date: 2009
  2. By: Oniang'o, Ruth
    Keywords: Food, Nutrition, Food emergencies, food security, Hunger, malnutrition, Disease, Risk assessment, HIV/AIDS,
    Date: 2009
  3. By: Fenske, James (Yale University)
    Abstract: I show how abundant land and scarce labor shaped African institutions before colonial rule. I present a model in which exogenous suitability of the land for agriculture and endogenously evolving population determine the existence of land rights, slavery, and polygyny. I then use cross-sectional data on pre-colonial African societies to demonstrate that, consistent with the model, the existence of land rights, slavery, and polygyny occurred in those parts of Africa that were the most suitable for agriculture, and in which population density was greatest. Next, I use the model to explain institutions among the Egba of southwestern Nigeria from 1830 to 1914. While many Egba institutions were typical of a land-abundant environment, they sold land and had disputes over it. These exceptions were the result of a period of land scarcity when the Egba first arrived at Abeokuta and of heterogeneity in the quality of land.
    JEL: N57 O10
    Date: 2009–11
  4. By: Ariga, Joshua; Jayne, Thomas S.
    Keywords: millions fed, food security, Fertilizer, maize, Liberalization market,
    Date: 2009
  5. By: Mekonnen, Alemu (Department of Economics, Addis Ababa University); Köhlin, Gunnar (Department of Economics, School of Business, Economics and Law, Göteborg University)
    Abstract: This paper looks at the fuel choice of urban households in major Ethiopian cities, using panel data collected in 2000 and 2004. It examines use of multiple fuels by households in some detail, a topic not much explored in the household fuel-choice literature in general, and in sub-Saharan Africa in particular. The results suggest that as households’ total expenditures rise, they increase the number of fuels used, even in urban areas, and they also spend more on the fuels they consume (including charcoal but not wood). The results also show that even fuel types such as wood are not inferior goods. The results support more recent arguments in the literature (using Latin American and Asian data) that multiple fuel use (fuel stacking) better describes fuel-choice behavior of households in developing countries, as opposed to the idea that households switch (completely) to other (more expensive but cleaner) fuels as their incomes rise. This study shows the relevance of fuel stacking (multiple fuel use) in urban areas in sub-Saharan Africa. While income is an important variable, the results of this study suggest the need to consider other variables such as cooking and consumption habits, dependability of supply, cost, and household preferences and tastes to explain household fuel choice, as well as to recommend policies that address issues associated with household energy use.<p>
    Keywords: Household fuel; urban; Ethiopia
    JEL: D11 O12
    Date: 2009–11–30
  6. By: Leung, Ron (African Development Bank); Stampini, Marco (African Development Bank); Vencatachellum, Désiré (African Development Bank)
    Abstract: The financial and economic crisis of 2008 and 2009 has taken its toll on the South African economy. The economy contracted for the first time since 1998, and entered recession during the fourth quarter of 2008. The GDP contraction was soon transmitted to the labor market. Between the second quarters of 2008 and 2009, employment fell by 3.8 percent. However, not all individuals were hit with the same intensity. Using labor force survey data unique in the African context, we find that human capital provided a buffer against the shock. After controlling for observable characteristics, education and experience showed the potential to entirely offset the effect of the recession on the likelihood of employment. This has important policy implications, as it strengthens the case for strategic investments in human capital, and helps identifying the unskilled as those with the highest need for social safety net interventions during the recession.
    Keywords: labor markets, South Africa, financial crisis, human capital, business cycle, emerging economies
    JEL: J2 E3
    Date: 2009–12
  7. By: Kassie, Menale (Environmental Economics Policy Forum for Ethiopia and Ethiopian Development Research Institute); Holden, Stein (Department of Economics and Resource management, Norwegian University of Life Sciences); Köhlin, Gunnar (Department of Economics, School of Business, Economics and Law, Göteborg University); Bluffstone, Randy (Department of Economics, Portland State University)
    Abstract: This study measures the impact of fanya juu bunds (an important soil and water conservation technology and the most popular type of contour bund in east Africa) on the value of crop production in a high-rainfall area in the Ethiopian highlands using cross-sectional multiple plot observations. We applied switching regression, stochastic dominance analysis (SDA), and decomposition and propensity score matching methods to ensure robustness. The switching regression, SDA, and decomposition analyses relied on matched observations, which was important because regression and SDA often do not ensure that comparable plots with conservation technology (conserved) and plots without (unconserved) actually exist in the distribution of covariates. All models told a consistent story that the value of crop production for plots with bunds was lower than for plots without bunds. In addition, the yield decomposition results showed that, although there was little difference in endowments between conserved and unconserved plots, the returns to endowments were substantially higher for unconserved plots. Based on these findings, it was hard to avoid the conclusion that these technologies might reduce soil erosion and associated off-site effects, but they did so at the expense of poor farmers in the Ethiopian highlands. We concluded that unless productivity was increased—for example by increasing fodder grass production on bunds—fanya juu bunds reduced on-farm production and therefore could not be characterized as a “win-win” measure to reduce soil erosion.
    Keywords: Ethiopia; soil conservation; matched data; decomposition
    JEL: C21 C23 Q12 Q15 Q16
    Date: 2009–11–30
  8. By: Yvan Guichaoua (Queen Elizabeth House, University of Oxford)
    Abstract: The paper discusses the recently promoted view that organized insurgent violence should either be conducted by activists bonded together by social capital ties or self-interested quasi-mercenaries, depending on the type of financial resources available to the group. We contrast this perspective with the study of an ethnic Nigerian militia, the Oodua People’s Congress (OPC). It appears that the success of this militia over time was jointly sustained by important preexisting social connections and numerous opportunities for economic gains. The perpetuation of OPC, we argue, is ensured by a ‘moral economy’ whose members enjoy selfinsurance in an environment perceived as unsafe.
    Keywords: Militias, Violent Mobilization, Extra-legal Governance, Security, Africa, Nigeria
    Date: 2009
  9. By: Andreas Mehler (GIGA Institute of Global and Area Studies)
    Abstract: Little attention has been paid to the factual effect of the state’s security forces on the security of African citizens. Reports about security forces’ contribution to widespread insecurity are frequent: the protectors become violators and their appearance causes fear, not security. In many African crisis countries the realization of better security forces appears to be an elusive goal, either because violent conflicts are not definitively settled and therefore do not allow for decent reform or because a lack of capacity as a result of material constraints is not easy to remedy. The self-help mechanisms used to compensate for the lack of state-sponsored security need more attention. However, it has to be acknowledged that the ideal of a neutral and effective force loyal to the state is shared by a great majority of the population. This contribution compares the experiences of Liberia and the Central African Republic, two extreme cases of strong and weak international involvement, respectively, in post-conflict security-sector reform.
    Keywords: Liberia, Central African Republic, security, armed forces, security-sector reform
    Date: 2009–11
  10. By: Witt, Rudolf; Waibel, Hermann
    Abstract: In this paper the class of Lower Partial Moments (LPMs) is used for measuring vulnerability as downside risk of household income in rural Cameroon. This class of established and coherent risk measures has been shown to meet a number of desirable properties. Among others, the LPMs fulfill the focus axiom, and for order greater than zero they are in harmony with expected utility theory under the weak assumption of risk aversion. Through combining the vulnerability measure with a portfolio approach it is possible to distinguish different livelihood systems for which the poverty and vulnerability measures are the explicit result of stochastic distributions of single activities in the households' portfolio and their covariance structure. In particular we consider the four major income generating activities in the study area: Sorghum, millet and rice production, and fishing. The results suggest that in the study area fishermen are less affected by adverse effects on income than other livelihood systems, while rice growers are the poorest and most vulnerable. It is also shown that rice and millet growers are suffering from chronic poverty, while transient poverty is more prevalent among the group of sorghum growers and fishermen. This implication is further confirmed by assuming a moving target equal to the mean portfolio income for the calculation of LPMs. The results of the scenario analysis suggest that policy interventions aiming at a reduction of the covariation structure between income flows from different activities are quite promising.
    Keywords: Vulnerability as expected poverty, Lower Partial Moments, portfolio theory, diversification, Sub Saharan Africa
    JEL: I32 O13 G11 G32
    Date: 2009–11
  11. By: Constant, Amelie F. (DIW DC, George Washington University); Tien, Bienvenue (DIW DC)
    Abstract: Economic reasons along with cultural affinities and the existence of networks have been the main determinants explaining migration flows between home and host countries. This paper reconsiders these approaches combined with the gravity model and empirically tests the hypothesis that ex-colonial links can still play an important role in the emigration decision. We employ a general linear mixed model, and apply it to the case of skilled, educated and talented Africans, who migrate to Fortress Europe over the period of 1990 to 2001. While we find some differences in the exodus of skilled Africans by sub-regions, the magnitude of the colonial vestige in Africa is a significant determinant of emigration flows. Overall, Portugal is preferred to the UK which is preferred more than Belgium, Germany and Italy. Brainy Africans are, however, indifferent between the UK, France and Spain as a destination country. Established immigrant networks and higher standards of living with job opportunities in the host country are also very important drivers of the emigration of brainy Africans to the European ex-colonial powers.
    Keywords: skilled migration, Africa, colonization, networks, economic reasons
    JEL: F22 O15 J61
    Date: 2009–12
  12. By: Kassie, Menale (Environmental Economics Policy Forum for Ethiopia, Ethiopian Development Research Institute); Pender, John (International Food Policy Research Institute, Washington, DC); Yesuf, Mahmud (Environmental Economics Policy Forum for Ethiopia, Ethiopian Development Research Institute); Köhlin, Gunnar (Department of Economics, School of Business, Economics and Law, Göteborg University); Mulugeta, Elias (International Livestock Research Institute)
    Abstract: Land degradation has been one of the major areas of concern in Ethiopia. Governments and development agencies have invested substantial resources to promote land management technologies and reduce land degradation. However, there is little understanding of the impacts that land management technologies have on yield and yield variability. This paper investigates the impact of stone bunds on mean yield and variance of yield, using multiple plot observations per household in low- and highrainfall areas of the Ethiopian highlands. Our analysis incorporated the propensity score matching method, stochastic dominance analysis, and exogenous and endogenous switching regression methods. We found statistically significant and positive impact of stone bunds on yield in low-rainfall areas. This did not hold in high-rainfall areas. We did not find a statistically significant stone-bund impact on production risk in either high- or low-rainfall areas. The results were robust to both parametric and nonparametric analysis. The overall conclusion from the analysis is that the performance of stone bunds varies by agro-ecology type. This implies the need for designing and implementing appropriate technologies that enhance productivity and are better adapted to local conditions.<p>
    Keywords: Switching regression; stochastic dominance; propensity score matching; stone bunds; yield; yield risk; Ethiopia
    JEL: C35 O33 Q15 Q24
    Date: 2009–11–30
  13. By: Kaminski, Jonathan; Headey, Derek; Bernard, Tanguy
    Keywords: millions fed, food security, Cotton, Burkinabe, Reform, SOFITEX, CFDT,
    Date: 2009
  14. By: Kassie, Menale (Environmental Economics Policy Forum for Ethiopia, Ethiopian Development Research Institute); Yesuf, Mahmud (Environmental Economics Policy Forum for Ethiopia, Ethiopian Development Research Institute); Köhlin, Gunnar (Department of Economics, School of Business, Economics and Law, Göteborg University)
    Abstract: This paper provides empirical evidence of production risk impact on sustainable land- management technology adoption, using two years of cross-sectional plot-level data collected in the Ethiopian highlands. We used a moment-based approach, which allowed a flexible representation of the production risk (Antle 1983, 1987). Mundlak’s approach was used to capture the unobserved heterogeneity along with other regressors in the estimation of fertilizer and conservation adoption. The empirical results revealed that impact of production risk varied by technology type. Production risks (variance and crop failure as measured by second and third central moments, respectively) had significant impact on fertilizer adoption and extent of adoption. However, this impact was not observed in adoption of conservation technology. On the other hand, expected return (as measured by the first central moment) had a positive significant impact on both fertilizer (adoption and intensity) and conservation adoption. Economic instruments that hedge against risk exposure, including downside risk and increase productivity, are important to promote adoption of improved technology and reduce poverty in Ethiopia.<p>
    Keywords: Production risk; sustainable land management technology adoption; moment based estimation; Ethiopia
    JEL: C33 D13 D81 O33 Q24
    Date: 2009–11–30
  15. By: Ole Boysen (Institute for International Integration Studies, Trinity College Dublin; Department of Economics, Trinity College Dublin)
    Abstract: How does an increase in food prices at the border impact poverty in Uganda given the strong spatial heterogeneity of the country and its limited domestic transportation and communication networks? Recently, a number of studies on the impact of international food prices on poverty in developing countries have been published. However, the role of spatial price transmission in this context remains largely unexplored. This paper targets that niche. We assess the spatial variability and transmission of prices through the analysis of time series and household data using descriptive statistics and regression methods. Subsequently, we apply the findings in a simulation experiment to determine the first-order poverty impacts of a hypothetical 50% increase in border prices for food under the assumption of imperfect spatial price transmission. The poverty results show impacts substantially different from those of a perfect price transmission scenario and also display strong regional differentiation.
    Keywords: Uganda, food prices, poverty, spatial price transmission
    JEL: D31 I32 Q18 Q55
    Date: 2009–11
  16. By: Yesuf, Mahmud (Environmental Economics Policy Forum for Ethiopia, Ethiopian Development Research Institute); Köhlin, Gunnar (Department of Economics, School of Business, Economics and Law, Göteborg University)
    Abstract: This paper investigates the impacts of market and institutional imperfections on technology adoption in a model that considers fertilizer use and soil conservation to be joint decisions. Controlling for plot characteristics and other factors, we found that a household’s decision to adopt fertilizer significantly and negatively depends on whether the same household adopts soil conservation. The reverse causality, however, was insignificant. We also found that outcomes of market imperfections, such as limited access to credit, plot size, risk considerations, and rates-of-time preference, were significant factors in explaining variations in farm technology adoption decisions. Relieving the existing market imperfections will most likely increase the adoption rate of farm technologies.<p>
    Keywords: Bivariate probit; fertilizer adoption; market imperfections; risk aversion; time preferences; soil conservation
    JEL: C35 D43 Q12 Q24
    Date: 2009–11–30
  17. By: Medhin, Haileselassie A. (Environmental Economics Policy Forum for Ethiopia and Ethiopian Development Research Institute); Köhlin, Gunnar (Department of Economics, School of Business, Economics and Law, Göteborg University)
    Abstract: This study adopts the stochastic metafrontier approach to investigate the role of soil conservation in small-scale highland agriculture in Ethiopia. Plot-level stochastic frontiers and metafrontier technology-gap ratios were estimated for three soil-conservation technology groups and a group of plots without soil conservation. Plots with soil conservation were found to be more technically efficient than plots without. The metafrontier estimates showed that soil conservation enhances the technological position of naturally disadvantaged plots.<p>
    Keywords: Soil conservation; technical efficiency; metafrontier; technology adoption; Ethiopia
    JEL: L25 Q12 Q16
    Date: 2009–11–30
  18. By: Ole Boysen (Institute for International Integration Studies, Trinity College Dublin; Department of Economics, Trinity College Dublin); Alan Matthews (Institute for International Integration Studies, Trinity College Dublin; Department of Economics, Trinity College Dublin)
    Abstract: This paper analyses the poverty impacts of an economic partnership agreement (EPA) between Uganda and the EU. As Ugandan exports are also eligible for duty-free access to the EU under the Everything But Arms scheme the main EPA-induced change will be the requirement to liberalise EU exporters' access to the Ugandan market. Fears have been raised that this could threaten the livelihoods of poor people through lower prices for agricultural commodities, crowding out of vulnerable industries, and loss of government revenue. In an attempt to address these concerns, we assess the impact potential of an EPA using descriptive statistics of Ugandan trade, social accounting matrix, and household budget survey data. Subsequently, we quantify the impacts on the economy and poverty, in particular, by conducting a simulation study based on a combined CGE-microsimulation model. The descriptive analysis suggests very limited scope for trade liberalisation with the EU and that the poor, in particular, have only weak links to formal markets. The results from the simulation of alternative EPA scenarios show minor but positive macroeconomic impacts indicating potentially low economic adjustment costs. Whether the very small poverty effects emerge positive or not depends on the selection of sensitive products in the EPA. Nevertheless, the very poorest appear to lose under all scenarios.
    Keywords: economic partnership agreements, Uganda, poverty, CGE, microsimulation
    JEL: D31 D58 F13 F14 I32 O55
    Date: 2009–11
  19. By: Nyangena, Wilfred (School of Economics, University of Nairobi); Köhlin, Gunnar (Department of Economics, School of Business, Economics and Law, Göteborg University)
    Abstract: Productivity gains from soil and water conservation (SWC) have empirical support in research stations. Previous empirical results from on-farm adoption of SWC are, however, varied. This study investigated the impact of soil conservation investment on farm productivity in three regions in Kenya. Using plot-level survey data, we focused on land productivity on plots with and without SWC. We tested the overall soil conservation hypothesis that increased SWC is beneficial for yield, as well as more specific hypotheses that SWC affects levels of inputs, returns from these inputs, and crop characteristics. The results showed a mixed picture where plots without SWC generally have higher yield values per hectare. However, plots with SWC are significantly steeper and more eroded than plots without SWC. A more careful analysis of a two-stage random effects–switching regression estimation comparing three SWC technologies to plots without SWC indicated that SWC increased the returns from degraded plots and sometimes from other inputs. A simulation exercise based on these estimations also showed that, in most cases, adoption has been beneficial for those who have done it and would be beneficial for those who have not.<p>
    Keywords: Kenya; soil conservation; switching regression; rural households; yields
    JEL: D61 Q12 Q16
    Date: 2009–11–30
  20. By: Yesuf, Mahmud (Environment for Development-Kenya, Kenyan Institute for Public Policy Research and Analysis (KIPPRA)); Kassie, Menale (Department of Economics, School of Business, Economics and Law, Göteborg University); Köhlin, Gunnar (Department of Economics, School of Business, Economics and Law, Göteborg University)
    Abstract: In countries where insurance and credit markets are thin or missing, production and consumption risks play a critical role in the choice and use of production inputs and adoption of new farm technologies. In this paper, we investigated impacts of chemical fertilizer and soil and water conservation technologies adoption on production risks, using a moment-based approach and two years of cross-sectional data. A pseudo-fixed-effect model was estimated to generate first, second, and third moments of farm production. Our results revealed that fertilizer adoption reduces yield variability, but increases the risk of crop failure. However, adopting soil and water conservation technology has no impact on yield variability, but reduces the downside risk of crop failure. The results underscore that the risk implications of farm technology adoption vary by technology type. Furthermore, policies that promote adoption of fertilizers should be complemented by desirable instruments that hedge against downside risk. In that respect, if properly implemented, the safety net program and the weather insurance programs currently piloted in some parts of Ethiopia are actions in the right direction.<p>
    Keywords: production risks; farm technology; moment-based approach; Ethiopia
    JEL: C33 D21 Q16 Q24
    Date: 2009–11–30
  21. By: Muchapondwa, Edwin (School of Economics, University of Cape Town); Sterner, Thomas (Department of Economics, School of Business, Economics and Law, Göteborg University)
    Abstract: This paper investigates whether the risk faced by rural farmers in Zimbabwe could poten- tially be managed by using community-based wildlife conservation. Community-based wildlife conservation could be an additional asset in the rural farmers’ investment portfolio thereby potentially diversifying and consequently reducing the risk they face. Such investment could also help e¤orts to conserve wildlife. By making use of national historical data and statistical analysis, this paper …nds that community-based wildlife conservation is a feasible hedge asset for agricultural production in rural Zimbabwe. The bene…ts of diversi…cation into community-based wildlife conservation are likely to be high only in those rural areas that can sustain wildlife pop- ulations su¢cient to generate adequate returns from wildlife activities such as tourism, trophy hunting, live animal sales and meat cropping.<p>
    Keywords: CAMPFIRE; diversi…cation; risk management; wildlife conservation; Zimbabwe
    JEL: D81 G11 Q29
    Date: 2009–12–03
  22. By: Reij, Chris; Tappan, Gary; Smale, Melinda
    Keywords: millions fed, food security, Sahel, Zai, Stone bunds, Agroforestry, Soil management,
    Date: 2009

This nep-afr issue is ©2009 by Quentin Wodon. It is provided as is without any express or implied warranty. It may be freely redistributed in whole or in part for any purpose. If distributed in part, please include this notice.
General information on the NEP project can be found at For comments please write to the director of NEP, Marco Novarese at <>. Put “NEP” in the subject, otherwise your mail may be rejected.
NEP’s infrastructure is sponsored by the School of Economics and Finance of Massey University in New Zealand.