Master of Agribusiness / Department of Agricultural Economics / Vincent Amanor-Boadu / The literature shows that increases in incomes lead to changes in the allocation of income or expenditure shares to different food products. The purpose of this thesis is to identify the effect of income on expenditure share allocations among different food groups. The study was particularly interested in beans and how changes in incomes affect the share of bean expenditures. We used data from the 2010 Zambia Living Conditions Monitoring Survey (LCMS). The LCMS covers the whole country and provides segmentation of the respondents, across the region and rural versus urban. It also provides detailed information on the income and expenditure distributions of respondent households. This allowed for the achievement of the overall objective of this thesis: understanding how beans and other food products responded to income changes as well as other demographic and socio-economic variables. The food share is the proportion of total household income that was allocated to food. The results show that food averages about 40% of income but varied significantly across the four income groups. It was 92% for those earning less than ZMW300 per month and 37% for those earning between ZMW300 and ZMW750 per month. It was down to 22.6% for those earning between ZMW750 and ZMW2.1 million per month had a food share of total income of only 10.8%, similar to the average U.S. consumer. These averages were found to be statistically different across the income groups. We found that Zambians allocated about 40% of their food expenditure to cereals compared to 5% to pulses and 3.5% to beans. They allocated a higher proportion of their food expenditure to fruits and vegetables than to beans and/or to pulses. This shows that legumes are very low on the food hierarchy in Zambia. However, across income categories, it was found that consumers in the second income group (ZMW300 and ZMW750 per month) allocated the most of their food expenditure to beans, about 3.9%, while those in the highest income group (ZMW750 and ZMW2.1 million per month ) allocated the least, about 3%. The biggest influencing demographic factor for pulses and beans’ shares of food expenditure was locale, with urban consumers having about 1.1 and 0.8 percentage points higher share of food expenditures allocated to beans than rural consumers. The respective t-values were 15.58 and 16.96. All the demographic and socio-economic variables were statistically significant at or below the 5% level. There was no difference between the allocation of people in the highest income group and those in the lowest income group. The results suggest that if the long-term objective is to reap the nutritional benefits of beans, there may be value in focusing on two principal policy variables: education and income enhancement. However, because education is correlated with income, the benefits of undertaking this policy initiative would more than benefit the bean consumption. It should unleash across the economy a more productive workforce that understands the health benefits of its food choices.

Diese Forschung dokumentiert einen nachhaltigen Bruch im 30-jährigen Rückgang des Anteils der Arbeitseinkommen nach der globalen Finanzkrise, der in den meisten Ländern konsistent und robust gegenüber verschiedenen Methoden ist. Seit 2008 haben sich die Arbeitseinkommensanteile in fortgeschrittenen Volkswirtschaften stabilisiert und in Entwicklungsländern erhöht, angetrieben durch ein stärkeres Wachstum des Kapital-Output-Verhältnisses in Entwicklungsländern, wie es durch eine neuartige Anwendung des Solow-Wachstumsmodells erklärt wird. Zweitens zeigt diese Dissertation mithilfe eines Ramsey-Modells, dass Handels- und Kreditbeschränkungen ein langfristiges Gleichgewicht schaffen, in dem der Süden und der Norden zu unterschiedlichen Pro-Kopf-Einkommen mit unterschiedlichen Raten konvergieren, während ihre Leistungsbilanzen unausgeglichen bleiben. Handel steigert langfristig das Pro-Kopf-Kapital im Vergleich zur Autarkie, wobei der Norden stärker profitiert. Das weltweite Durchschnittseinkommen ist jedoch am höchsten, wenn die Kreditbeschränkungen aufgehoben werden. Drittens überprüft diese Arbeit die Evidenz für konditionale Konvergenz im Zeitraum 1960–2017 über 130 Länder hinweg und zeigt, dass Entwicklungsländer schneller konvergieresn als fortgeschrittene Volkswirtschaften – ein statistisch signifikanter und robuster Befund. Zudem untersucht sie drei Aspekte der unbedingten Konvergenz: die Relevanz von Länder-Fixeffekten, die Häufigkeit unbedingter Konvergenz und den Zusammenhang zwischen Aufholprozessen und negativen Steigungskoeffizienten in Wachstumsregressionen. Die ersten beiden Aspekte stützen die Hypothese der konditionalen Konvergenz. / This research documents a sustained post-crisis break in the 30-year decline of the labor share, consistent across most countries and robust to various methods. Since 2008, labor shares have stabilized in advanced economies and risen in developing ones, driven by stronger capital–output growth in developing economies, as explained by a novel application of the Solow growth model. Second, using a Ramsey model, this dissertation shows that trade and borrowing constraints create a long-run equilibrium where South and North converge to different per capita incomes at different rates, with unbalanced current accounts. Trade raises long-run per capita capital compared to autarky, benefiting the North more. World average income is highest, however, when the borrowing constraint is eliminated. Third, this work reassesses the evidence on conditional convergence from 1960–2017 across 130 countries, showing faster convergence rates for developing countries than advanced ones—a statistically significant and robust result. It also examines three aspects of unconditional convergence: the relevance of country fixed effects, the commonality of unconditional convergence, and the link between catch-up and negative slope coefficients in growth regressions. The first two aspects support the conditional convergence.