David Stifel

Progress Toward the Millennium Development Goals in Africa

We analyze demographic and health surveys to examine the progress of African countries in achieving six of the seven millennium development goals (MDG) set forth by the United Nations. Our results paint a discouraging picture. Despite some noteworthy progress, the evidence suggests that, in the absence of dramatic changes in the rates of improvement in most measures of living standards, the MDG will not be reached for most indicators in most countries. The results are particularly sobering for rural areas, where living standards are universally lower, and where rates of progress lag behind urban areas.

Transactions Costs and Agricultural Productivity: Implications of Isolation for Rural Poverty in Madagascar

This paper examines the mechanisms that transmit isolation into poverty in Madagascar using household survey data combined with a census of administrative communes. Given the importance of agriculture to the rural poor, where nine out of ten poor persons is engaged in farming, we concentrate on isolation manifesting itself in the form of high transaction costs such as the cost of transporting agricultural commodities to major market centers. We find that (a) the incidence of poverty in rural Madagascar increases with remoteness; (b) yields of major staple crops fall considerably as one gets farther away from major markets; (c) and the use of agricultural inputs declines with isolation. Simulation results using output from rice production function estimates suggest that halving travel time per kilometer on major highways (feeder roads) will increase primary season rice production by 1.3 (1.0) percent.

Parental Preferences for Nutrition of Boys and Girls: Evidence from Africa

This article models the determinants of pre-school age malnutrition in Africa using the Demographic Health Surveys. By examining the differences in the impact of mothers and fathers education on the nutrition of boys and girls, we draw inferences from our reduced-form equations regarding the existence of non-unified preferences. In a bargaining framework, women with more schooling are able to earn more, which improves their fallback position. Thus, we test whether mothers schooling has a larger impact on daughters than sons nutrition, and whether fathers education favors sons nutrition. Using classical testing criteria, we generally find that preferences of fathers and mother differ in regard to the health of boys and girls.

A dual-dual CGE model of an archetype African economy: trade reform, migration and poverty

Abstract We build a CGE model of an archetype African economy to simulate the welfare effects of trade liberalization specifically on poverty. The economy is modeled following a dual-dual framework (Thorbecke, 1993, 1994, 1997) that is characteristic of the structure of a developing country in its middle development phase. This provides the basis for analyzing the distribution of modern and informal sector activities in both rural and urban areas. The interdependence of these four broadly defined sectors is modeled not only in terms of production and consumption decisions within them, but also in terms of labor migration among them, adding a richness which is missing in the standard CGE models. Poverty analysis is integrated in the CGE methodology by endogenizing both intra-group income distributions and the nominal poverty line. The application of standard poverty measures to the pre- and post-simulation poverty lines and distributions of income for each socio-economic group, allows the assessment of policy-induced changes on group specific poverty and national poverty. Simulations with a model calibrated from a social accounting matrix (SAM) of a prototype African economy, show that an important contribution of the dual-dual model vis-a-vis poverty analysis in a CGE model is the inter-group migration it incorporates. Changes in the population shares of the socio-economic groups that follow population shifts have important implications for the magnitudes of changes in national poverty.

Robust Comparisons of Malnutrition in Developing Countries

We use Demographic and Health Surveys (DHS) to make international and inter-temporal welfare comparisons. While most poverty analyses rely on expenditures or income, we use anthropometric measures of nutrition as indicators of living standards. The advantages are that we observe individual—not household—well-being, deflators and exchange rates are unnecessary, and measurement techniques are similar across surveys. We test the robustness of the headcount results, and find that applying higher order Foster-Greer-Thorbecke poverty measures adds little information; although stochastic dominance testing of nutrition distributions reveals that changes in malnutrition are sensitive to the choice of the “nutrition poverty line”. Copyright 2002, Oxford University Press.

Childhood overweight in the United States: a quantile regression approach.

The prevalence of overweight children in the United States has increased dramatically over the past two decades, and is creating well-known public health problems. Moreover, there is also evidence that children who are not overweight are becoming heavier. We use quantile regression models along with standard ordinary least squares (OLS) models to explore the correlates of childhood weight status and overweight as measured by the Body Mass Index (BMI). This approach allows the effects of covariates to vary depending on where in the BMI distribution a child is located. Our results indicate that OLS masks some of the important correlates of child BMI at the upper and lower tails of the weight distribution. For example, mothers education has no effect on black children, but is associated with improvements in BMI for overweight white boys and underweight white girls. Conversely, mothers cognitive aptitude has no effect on white boys, but is associated with BMI improvements for underweight black children and overweight white girls. Further, we find that underweight white children and black girls experience similar improvements in BMI as they get older, but that for black boys there is little if any association between age and BMI anywhere in the BMI distribution.

Race and gender differences in the cognitive effects of childhood overweight

The increase in the prevalence of overweight children (ages 6–13 years) in the United States over the past two decades is likely to result in adverse public health consequences. We use data from the children of the National Longitudinal Survey of Youth 1979 cohort to investigate an additional consequence of childhood overweight – its effect on relative cognitive development. To control for unobserved heterogeneity, we estimate individual (child) fixed effect (FE) models and instrumental variable (IV) models. Although recent research suggests that there is a negligible effect of childhood overweight on cognitive ability, our results demonstrate that the effects are uncovered when examining the relationship separately by race. In particular, we find that overweight white boys have math and reading scores approximately an SD lower than the mean. Overweight white girls have lower math scores whereas overweight black boys and girls have lower reading scores. Our results suggest that in addition to well-documented health consequences, overweight children may also be at risk in terms of experiencing adverse education outcomes, which could lead to lower future wages.

Structural Transformation of Cereal Markets in Ethiopia

Abstract We study cereal markets in Ethiopia over the last decade, a period that has been characterised by important local changes, including strong economic growth, urbanisation, improved road and communication infrastructure, and higher adoption of modern inputs in agriculture. These changes are associated with better spatial price integration as well as with significant declines in real price differences between supplying and receiving markets and in cereal milling and retail margins. In short, important improvements have occurred in Ethiopia’s cereal marketing system. This is especially important because dysfunctional cereal markets were previously identified as an important cause of food insecurity in the country.

Taboos, agriculture and poverty

Abstract We study the impact of work taboos (fady days) on agriculture and poverty. Using cross-sectional data from a national household survey for Madagascar, we find that 18 per cent of agricultural households have two or more fady days per week and that an extra fady day is associated with 6 per cent lower per capita consumption and 5 per cent lower rice productivity. To address the possible endogeneity of fady days, we present instrumental variable estimates and heterogeneous effect regressions using village fixed effects. We find that smaller households and those with less education employ less labour in villages with more fady days.

Economic Benefits of Rural Feeder Roads: Evidence from Ethiopia

Abstract We estimate households’ willingness-to-pay for rural feeder roads in Ethiopia. Using purposefully collected data, we compare the economic behaviour of households by remoteness to estimate the benefits of access to feeder roads. Although we cannot definitively assert a causal relationship, we cautiously estimate that gravel roads have internal rates of return of 12–35 per cent. These results suggest that rural feeder roads may have relatively high rates of return even in unfavourable settings where (a) small-scale farmers have low levels of marketed agricultural surplus, (b) non-farm earning opportunities are negligible, and (c) motorised transport services are not guaranteed.