Climate has relevant impacts on economic activities and human well-being. This study aims to contribute to the identification and measurement of these impacts on the agricultural markets and health. With regard to health, dengue fever - a climate-sensitive disease - is analyzed, as it affects thousands of Brazilians every year, generating large costs in both private and public markets (approximately US$800 million in Brazil in 2011). Thus, chapter 2 addresses the impact of climate on the risk of dengue fever in Brazil, modeling dengue incidence as a risk function estimated using count data models applied to the outbreak of dengue epidemics in 2010 and controlling for likely endogeneities. The results corroborate the relevance of climate variables in explaining dengue incidence in Brazil. Moreover, if climate change occurs as expected, the results suggest a potential added risk for central-southern areas in Brazil and a risk reduction for northern areas of the country. Short-term deviations from normal rainfall conditions in summer also seem to increase the risk of dengue when compared to normal rainfall conditions. Other results suggest the non-effectiveness of local expenditures for epidemiological surveillance and the need of integrated actions to control the disease. When it comes to agricultural markets, two important hypotheses are tested: i) farmers only observe the average climate conditions of their region when deciding the type and amount of crop/animal to grow/raise (Chapter 3); ii) weather diversions from normal climate conditions might deviate farmers from their optimal profits, causing inefficiencies (Chapter 4). Both hypotheses are not rejected by the data. The modeling approach used is the translog profit frontier approach. The results indicated that if the climate change forecasts are confirmed, almost all the agricultural products in Brazil will be negatively affected, especially production of cattle products (beef and milk), coffee and maize. The only product that shows a positive effect is soybeans, probably due to its current high adaptability to different climate patterns. Use of irrigation is the main compensation instrument to reduce the expected climate change impacts. However, technological instruments such as use of transgenic seeds, cattle confinement, along with the increase in tillage, are also important adaptation measures to climate change. The analysis of the determinants of the efficiencies calculated suggests that droughts and cold stresses cause harmful effects to agriculture in Brazil. In 2006, the estimated loss from rainfall anomalies is approximately 15 billion dollars (in 2011 values). The southern and midwestern regions are slightly more vulnerable than the other regions. Assuming the extreme hypothesis of drought and cold stress occurrence overall in Brazil, the total profit loss is about 81 and 35 billion dollars, respectively. These losses can be mainly mitigated by the intense use of an insurance instrument, but the participation of farmers in the agricultural insurance market in Brazil is still very low. / O clima impacta diversas atividades econômicas e humanas. Esta tese tem o objetivo de contribuir para a identificação e mensuração de alguns destes impactos, com foco nos mercados agrícolas e na saúde. Com relação à saúde, o dengue, que é uma doença sensível ao clima, é analisado uma vez que afeta milhares de brasileiros todos os anos e causa expressivas perdas para os mercados privados e para a saúde pública (cerca de US$800 milhões no ano de 2011 para o Brasil). Desta forma, o Capítulo 2 busca entender o impacto do clima no risco de dengue no país por meio da modelagem e estimação do risco de dengue usando dados da epidemia de 2010 e modelos de dados de contagem com controle das endogeneidades detectadas. Os resultados corroboram a relevância das variáveis climáticas na explicação da incidência de dengue no Brasil. Ademais, se as mudanças climáticas ocorrerem da forma esperada, os resultados sugerem um aumento do risco na região do Centro-Sul brasileiro e redução do risco no Norte-Nordeste. Desvios de curto prazo da precipitação no verão também parecem potencializar o risco da doença, quando comparado ao risco em condições pluviométricas normais. Outros resultados sugerem que as despesas municipais com vigilância epidemiológica não são efetivas no combate ao dengue e ações integradas são necessárias para o controle da doença no curto-prazo. Com relação aos mercados agrícolas, duas importantes hipóteses são testadas: i) fazendeiros apenas observam as condições climáticas médias de suas regiões no momento em que decidem o que e quanto produzir (Capítulo 3); ii) desvios climáticos de curto prazo podem afastar os fazendeiros de seus lucros ótimos, causando ineficiências (Capítulo 4). Ambas as hipóteses não são rejeitadas pelos dados. Para tal teste, estimou-se uma equação de fronteira de lucro com a especificação translog. Os resultados indicaram que, se confirmadas as mudanças climáticas, praticamente todos os produtos agrícolas serão negativamente afetados, especialmente a produção de leite, carne bovina, café e milho. O único produto positivamente impactado seria a soja, provavelmente devido à sua adaptabilidade a diferentes climas. O uso de técnicas de irrigação parece ser um importante instrumento de adaptação a tais mudanças. Todavia, outros instrumentos tecnológicos, tais como o uso de sementes transgênicas, confinamento de gado, assim como o uso de plantio direto, também se mostraram importantes técnicas de adaptação à evolução esperada do clima. A análise dos determinantes da eficiência agrícola sugere que secas e ondas de frio impactam negativamente a agricultura no Brasil. Em 2006, a perda agrícola estimada relacionada à falta de chuvas foi de aproximadamente 15 bilhões de dólares (em valores de 2011). As regiões Sul e Centro-oeste são sensivelmente mais vulneráveis do que as demais regiões. Assumindo a hipótese extrema de ocorrência de seca e onda de frio em todo o país, as perdas estimadas de tais eventos são da ordem de 81 e 35 bilhões de dólares, respectivamente. Essas perdas podem ser mitigadas pelo uso de seguros agrícolas, porém a participação de fazendeiros no mercado de seguro rural no Brasil é ainda muito baixa.

Structural Equations Models (SEMs) are now widely used almost in every discipline of research. Most of the existing materials for the Namibian macroeconomic models are studies of the well documented time series approach. In this study, we provided a statistical approach on modelling the Namibian macroeconomics for the real and fiscal economic sectors using SEMs. The approach is based on testing the theoretical specification laid down by the Namibian Macroeconometrics Model (NAMEX) of 2004. The economic structure and relationships among the variables is evaluated by means of exploratory and confirmatory analysis and the results are congruent to the existing theory in terms of loading patterns. Between Maximum Likelihood (ML) and Generalized Least Square (GLS) estimation methods, we compared the discrepancy of parameter estimates under the commonly encountered problems of sample size, violation of underlying assumptions in the data as well as model misspecifications. GLS estimation methods seem to provide better goodness of fit indices under those conditions. We have also shown that the fiscal sector is not well represented by our SEM. We recommend further studies to employ sufficiently larger samples so that models are correctly specified.

Si de nombreux efforts ont été déployés pour améliorer l’accès à l’éducation en Afrique subsaharienne, la proportion d’enfants qui interrompent leur scolarité avant la fin du cycle primaire reste encore très élevée. Pour tenter de répondre à ce défi majeur, cette thèse se propose d’examiner les déterminants de la demande d’éducation dans un environnement rural exposé à de nombreux risques. Le premier chapitre s’intéresse à la place essentielle, et pourtant peu étudiée, que tiennent les coûts d’opportunité du temps des enfants dans les choix éducatifs. Il s’avère dans ce cas nécessaire d’estimer la productivité du travail des enfants afin d’identifier les coûts susceptibles de compromettre leur scolarisation. Afin de mieux appréhender les choix en matière d’éducation, le deuxième chapitre dresse quant à lui une estimation des bénéfices de l’éducation dans un contexte agricole qui se distingue à la fois par un accès limité aux nouvelles technologies et par la prédominance d’exploitations familiales de petites tailles. Enfin, le troisième chapitre interroge les effets des chocs de productivité sur les décisions de scolarisation et sur les performances scolaires des enfants. Deux critères retiennent notre attention, l'âge auquel les enfants sont confrontés à ces chocs et leur intensité. Ce sujet nous semble d’autant plus pertinent que la fréquence de ces chocs ne cesse aujourd’hui d’augmenter. À travers ces trois chapitres centrés sur la Tanzanie rurale, cette thèse offre ainsi un aperçu du rôle des politiques publiques dans la protection et le développement de l’éducation. / Despite numerous investments that have been made to increase access to education in sub-Saharan Africa, a noteworthy share of children drop out of school prior to completing primary education. To address this issue, this thesis examines the factors that drive education decisions in a rural risky environment. The first chapter focuses on one of the core determinant of education investment that has been under-explored, the opportunity costs of education. To identify these costs that can significantly hinder education, we determine children's productivity on the farm and provide an estimate range of the value of one day of child labor. In order to better understand education decisions in rural sub-Saharan Africa, the second chapter assesses the different benefits of education in rural Tanzania, where family farm is the dominant structure in agriculture and where the technology level is low. Finally, the third chapter investigates whether productivity shocks are detrimental to educational achievement and children’s cognitive skills by considering two particular aspects, the age at which shocks occur, and the length of shocks. This subject is all the more relevant today when the number of productivity shocks is growing. Throughout these three chapters which focus on rural Tanzania, this thesis provides some insight into the role of public policies in protecting and promoting education.

Following the success of the Grameen Bank in Bangladesh, Microfinance institutions (MFIs) which apply group-lending method through the medium of small credit have been regarded as a new and effective tools for poverty alleviation for the poor in many Less Developed Countries. This study analyses the role of two MFIs, namely KUKESRA, a government administered programme and Mitra Karya East Java (MKEJ) which is a privately managed institution in poverty alleviation in Indonesia. It examines to what extent these institutions have been successful in helping the poor, and improving the living standards of the recipients. Two alternative approaches, namely the institutionalist and the welfarist approaches, are used to examine the question of whether the poor benefited from the two programmes, followed by a comparison of the performances between the two. Using data obtained from a sample survey of 393 respondents in the District of Malang in East Java, from December 1998 - June 1999, it was found that the differences in management, organisational structure, programme design, and the system of coordination all resulted in differences in performance of the two MFI institutions studied. It was found that both programmes increased the incomes of the recipients, but the impact of KUKESRA was much lower than that of MKEJ. However, KUKESRA had a greater positive effect on employment than MKEJ. Neither of the programmes resulted in a significant improvement in the consumption of basic needs of the recipients. Of the two approaches used in the evaluation of the programmes, a good performance in terms of outreach and sustainability under the institutional approach did not imply that the poor really benefited from the programme. It was found that the welfarist approach is much more appropriate in evaluating the effectiveness of MFIs in Indonesia.

Since the transformation from Political Economy to Economics and from Classical to Neoclassical theory in the late nineteenth century, a theory of human behavior has constituted the initial foundation upon which all economic theory is based and developed. Two main theories of human behavior developed by William Stanley Jevons and Carl Menger have been generally accepted to have ushered in this Marginalist Revolution. Jevons marginal utility theory popularized by Alfred Marshall is still extensively used today, while the Austrian approach of Menger was effectively removed from academic discussion in the nineteen thirties; mainly as a result of the annexation of Austria and the dissolution of the Austrian School of Economics. Given the inability of economists to fully operationalize the marginal utility theory and realistically explain and resolve a broad range of behavioral anomalies using Neoclassical and Post-Neoclassical Economics, this thesis attempts to examine and address the most fundamental issues of human behavior in economics to explain how utility theory and modern Neoclassical and Post-Neoclassical Economics are flawed and how a realistic theory of human behavior, developed from the scholarly work of the early Austrian Economists, can be used to develop the basis of a scientific economics, derived from observation, that holds the potential to both expand the scope of economic understanding, redirect the focus of the discipline, and possibly unify the many disparate theories in the field.

Since the transformation from Political Economy to Economics and from Classical to Neoclassical theory in the late nineteenth century, a theory of human behavior has constituted the initial foundation upon which all economic theory is based and developed. Two main theories of human behavior developed by William Stanley Jevons and Carl Menger have been generally accepted to have ushered in this Marginalist Revolution. Jevons marginal utility theory popularized by Alfred Marshall is still extensively used today, while the Austrian approach of Menger was effectively removed from academic discussion in the nineteen thirties; mainly as a result of the annexation of Austria and the dissolution of the Austrian School of Economics. Given the inability of economists to fully operationalize the marginal utility theory and realistically explain and resolve a broad range of behavioral anomalies using Neoclassical and Post-Neoclassical Economics, this thesis attempts to examine and address the most fundamental issues of human behavior in economics to explain how utility theory and modern Neoclassical and Post-Neoclassical Economics are flawed and how a realistic theory of human behavior, developed from the scholarly work of the early Austrian Economists, can be used to develop the basis of a scientific economics, derived from observation, that holds the potential to both expand the scope of economic understanding, redirect the focus of the discipline, and possibly unify the many disparate theories in the field.

The three branches of American government---judicial, legislative, and executive---serve important governmental roles, and present their own interesting political questions. We answer three here. First, what are the differences between judges and politicians, and how does this inform the formers' selection? Second, how do senators behave to satisfy their political preferences and the electorate's? Third, what is the optimal strategy for a candidate in the Electoral College? American states select judges in various ways. In Chapter 1, we analyze "merit selection." Typically, a nonpartisan commission culls applicants for judgeships, and an appointee is selected by the governor. Then, periodically, this judge undergoes a retention election: an up-or-down vote by the state's electorate. We contribute a microeconomic model to analyze these elections. We compare this institution, in welfare terms, to others used to appoint and retain judges. Finally, we analyze a recent and ongoing phenomenon: these elections are transforming from historically rubber stamp formalities into contested, politicized contests. The politicization of issues brought before courts increases the likelihood of judges being ousted. In Chapter 2, we explore the behavior of legislators in the U.S. Senate, and of the voters who elect them. We examine shifts in incumbent senators' espoused political positions over time, as the reelection campaign approaches. We introduce novel game theoretic models of incumbent-challenger interaction. We find, through empirical analysis of senators' roll call votes, that senators moderate their positions over time, as potential reelection approaches. Moreover, this moderation accelerates. This is explained by the behavior of voters: the moderation is mirrored by the attention paid by voters. Also, the identity of an incumbent's challenger plays an important role in the amount of moderation exhibited by the incumbent. In Chapter 3, we consider a highly adaptable game theoretic model of competition in the Electoral College. It takes the form of a repeated game. Candidates make allocation decisions to persuade voters. Candidates get utility from winning office, and disutility from expending resources. We characterize optimal campaign strategy, and present comparative statics. We show, inter alia, that a candidate with an inherent advantage may prefer a longer campaign. / text

This dissertation contains three chapters. Each applies the tools of applied microeconomics to questions in labor economics, the economics of education, and social economics, respectively. In the first chapter, which is joint work with Amanda Pallais, we present the results of a series of field experiments in an online labor market designed to test whether workers referred to a firm by existing employees perform differently from their non-referred counterparts and, if so, why. We find that referred workers have higher performance and lower turnover than non-referred workers. We demonstrate a large role for selection: referred workers perform better and persist longer even at jobs to which they are not referred at a firm where their referrers do not work. Team production is also important: referred workers are much more productive when working with their own referrer than with someone else's referrer. / Economics

Despite concerted research effort over the last thirty years, social capital remains a variably, and at times, ill-defined concept. A lack of a clear causal theory has made social capital difficult to explore in an empirical setting. In addition, limited understanding of the concept’s operation has restricted its ability to provide valuable insight into policy development. The three papers that compose this thesis examine the concept, measurement, and consequences of social capital. The first provides a theoretical discussion of the conceptual origins of the term, its common criticisms, and suggests an alternative approach to its understanding. The second applies this alternative approach to an empirical model of child enrolment in post-secondary education. Finally, the third critically examines a recent federal policy research initiative related to social capital, identifying key policy development advantages to this thesis’s alternative approach. This thesis argues that antecedents to the modern social capital literature along with more recent criticisms suggest a dual approach to understanding social capital. This dual approach involves two distinct frameworks for understanding the concept – one literal and one figurative. These frameworks guide alternative approaches to empirical social capital work, demonstrated through the analysis of social capital’s impact on child post-secondary enrolment. It further identifies how the two frameworks provide more relevant information on the operation of social capital, facilitating prospective policy development. Overall, the thesis concludes that the literal and figurative approaches represent a more useful way of understanding and applying the social capital concept.

Despite concerted research effort over the last thirty years, social capital remains a variably, and at times, ill-defined concept. A lack of a clear causal theory has made social capital difficult to explore in an empirical setting. In addition, limited understanding of the concept’s operation has restricted its ability to provide valuable insight into policy development. The three papers that compose this thesis examine the concept, measurement, and consequences of social capital. The first provides a theoretical discussion of the conceptual origins of the term, its common criticisms, and suggests an alternative approach to its understanding. The second applies this alternative approach to an empirical model of child enrolment in post-secondary education. Finally, the third critically examines a recent federal policy research initiative related to social capital, identifying key policy development advantages to this thesis’s alternative approach. This thesis argues that antecedents to the modern social capital literature along with more recent criticisms suggest a dual approach to understanding social capital. This dual approach involves two distinct frameworks for understanding the concept – one literal and one figurative. These frameworks guide alternative approaches to empirical social capital work, demonstrated through the analysis of social capital’s impact on child post-secondary enrolment. It further identifies how the two frameworks provide more relevant information on the operation of social capital, facilitating prospective policy development. Overall, the thesis concludes that the literal and figurative approaches represent a more useful way of understanding and applying the social capital concept.