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Ensaios sobre previsão de inflação e análise de dados em tempo real no BrasilCusinato, Rafael Tiecher January 2009 (has links)
Esta tese apresenta três ensaios sobre previsão de inflação e análise de dados em tempo real no Brasil. Utilizando uma curva de Phillips, o primeiro ensaio propõe um “modelo evolucionário” para prever inflação no Brasil. O modelo evolucionário consiste em uma combinação de um modelo não-linear (que é formado pela combinação de três redes neurais artificiais – RNAs) e de um modelo linear (que também é a referência para propósitos de comparação). Alguns parâmetros do modelo evolucionário, incluindo os pesos das combinações, evoluem ao longo do tempo segundo ajustes definidos por três algoritmos que avaliam os erros fora-da-amostra. As RNAs foram estimadas através de uma abordagem híbrida baseada em um algoritmo genético (AG) e em um algoritmo simplex de Nelder-Mead. Em um experimento de previsão fora-da-amostra para 3, 6, 9 e 12 passos à frente, o desempenho do modelo evolucionário foi comparado ao do modelo linear de referência, segundo os critérios de raiz do erro quadrático médio (REQM) e de erro absoluto médio (EAM). O desempenho do modelo evolucionário foi superior ao desempenho do modelo linear para todos os passos de previsão analisados, segundo ambos os critérios. O segundo ensaio é motivado pela recente literatura sobre análise de dados em tempo real, que tem mostrado que diversas medidas de atividade econômica passam por importantes revisões de dados ao longo do tempo, implicando importantes limitações para o uso dessas medidas. Elaboramos um conjunto de dados de PIB em tempo real para o Brasil e avaliamos a extensão na qual as séries de crescimento do PIB e de hiato do produto são revisadas ao longo do tempo. Mostramos que as revisões de crescimento do PIB (trimestre/trimestre anterior) são economicamente relevantes, embora as revisões de crescimento do PIB percam parte da importância à medida que o período de agregação aumenta (por exemplo, crescimento em quatro trimestres). Para analisar as revisões do hiato do produto, utilizamos quatro métodos de extração de tendência: o filtro de Hodrick-Prescott, a tendência linear, a tendência quadrática, e o modelo de Harvey-Clark de componentes não-observáveis. Todos os métodos apresentaram revisões de magnitudes economicamente relevantes. Em geral, tanto a revisão de dados do PIB como a baixa precisão das estimativas de final-de-amostra da tendência do produto mostraram-se fontes relevantes das revisões de hiato do produto. O terceiro ensaio é também um estudo de dados em tempo real, mas que analisa os dados de produção industrial (PI) e as estimativas de hiato da produção industrial. Mostramos que as revisões de crescimento da PI (mês/mês anterior) e da média móvel trimestral são economicamente relevantes, embora as revisões de crescimento da PI tornem-se menos importantes à medida que o período de agregação aumenta (por exemplo, crescimento em doze meses). Para analisar as revisões do hiato da PI, utilizamos três métodos de extração de tendência: o filtro de Hodrick-Prescott, a tendência linear e a tendência quadrática. Todos os métodos apresentaram revisões de magnitudes economicamente relevantes. Em geral, tanto a revisão de dados da PI como a baixa precisão das estimativas de final-de-amostra da tendência da PI mostraram-se fontes relevantes das revisões de hiato da PI, embora os resultados sugiram certa predominância das revisões provenientes da baixa precisão de final-de-amostra. / This thesis presents three essays on inflation forecasting and real-time data analysis in Brazil. By using a Phillips curve, the first essay presents an “evolutionary model” to forecast Brazilian inflation. The evolutionary model consists in a combination of a non-linear model (that is formed by a combination of three artificial neural networks - ANNs) and a linear model (that is also a benchmark for comparison purposes). Some parameters of the evolutionary model, including the combination weight, evolve throughout time according to adjustments defined by three algorithms that evaluate the out-of-sample errors. The ANNs were estimated by using a hybrid approach based on a genetic algorithm (GA) and on a Nelder-Mead simplex algorithm. In a 3, 6, 9 and 12 steps ahead out-of-sample forecasting experiment, the performance of the evolutionary model was compared to the performance of the benchmark linear model, according to root mean squared errors (RMSE) and to mean absolute error (MAE) criteria. The evolutionary model performed better than the linear model for all forecasting steps that were analyzed, according to both criteria. The second essay is motivated by recent literature on real-time data analysis, which has shown that several measures of economic activities go through important data revisions throughout time, implying important limitations to the use of these measures. We developed a GDP real-time data set to Brazilian economy and we analyzed the extent to which GDP growth and output gap series are revised over time. We showed that revisions to GDP growth (quarter-onquarter) are economic relevant, although the GDP growth revisions lose part of their importance as aggregation period increases (for example, four-quarter growth). To analyze the output gap revisions, we applied four detrending methods: the Hodrick-Prescott filter, the linear trend, the quadratic trend, and the Harvey-Clark model of unobservable components. It was shown that all methods had economically relevant magnitude of revisions. In a general way, both GDP data revisions and the low accuracy of end-of-sample output trend estimates were relevant sources of output gap revisions. The third essay is also a study about real-time data, but focused on industrial production (IP) data and on industrial production gap estimates. We showed that revisions to IP growth (month-on-month) and to IP quarterly moving average growth are economic relevant, although the IP growth revisions become less important as aggregation period increases (for example, twelve-month growth). To analyze the output gap revisions, we applied three detrending methods: the Hodrick-Prescott filter, the linear trend, and the quadratic trend. It was shown that all methods had economically relevant magnitude of revisions. In general, both IP data revisions and low accuracy of end-of-sample IP trend estimates were relevant sources of IP gap revisions, although the results suggest some prevalence of revisions originated from low accuracy of end-of-sample estimates.
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Convergência de renda e desenvolvimento regional no Paraná (1999-2006) / Income convergence and regional development in the Paraná State (1999-2006)Vieira, Fábio Lopes 03 September 2010 (has links)
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Previous issue date: 2010-09-03 / The main objective of this study comprises the analysis of the distribution of municipal income per capita in the Paraná state, in the period 1999-2006. Economy that arises as the fifth most expressive of Brazil, is characterized by a reasonable rent for domestic and large regional disparities. This last feature has motivated this study, which sought to verify the occurrence of convergence of per capita income among the municipalities. For this venture, we used the AEDE and spatial econometric model for panel data with fixed effects, estimated by MQO, using the computer program GeoDa. We used four proxies of explanatory variables which: Productive Capital, Human Capital, Natural Capital and the natural logarithm Neperiano of GDP per capita and the dependent variable, the growth rate of GDP per capita municipal. It was evident that some factors potentiate the process of local economic growth, there is the productive capital, that among the variables, played a major positive role. Human Capital already had secondary importance, and Natural Capital, did not appreciably affect growth. The results also showed that spatiality has proved extremely important factor for the Parana s economy, suggesting that the economic performance of a particular locality, in general, is directly influenced by the performance of its neighbors. It should also be noted that even municipalities sharing some common characteristics, idiosyncrasies and potential sites have played key role in the growth rates. In short, the analysis revealed that the disparities in per capita income tended to decrease between the Parana s municipal economies, in a context established, evidenced the occurrence of convergence of per capita income, either absolutely or conditionally, demonstrating that economic development is tending to spread state by geographic areas. However, it is estimated they would need nearly 59 years for the differences in income per capita municipal reached the half-life, which characterizes the need for public politics aimed at reducing these disparities, since the convergence even tending to occur, is quite slow between the municipalities of Paraná. / O objetivo principal deste estudo compreende a análise da distribuição municipal de renda per capita do Estado do Paraná, no período de 1999-2006. Economia que se coloca como a 5a mais expressiva do Brasil, é caracterizada pela razoável renda relativa e grandes disparidades regionais internas. Esta última particularidade motivou este estudo, o qual buscou verificar a ocorrência da convergência de renda per capita entre os municípios do Estado. Para esta empreitada utilizou-se a AEDE e a modelagem econométrica espacial para dados de painel com efeitos fixos, estimada por MQO, através do programa computacional GeoDa. Foram empregadas 4 proxies de variáveis explicativas sendo: Capital Produtivo, Capital Humano, Capital Natural e o logaritmo neperiano do PIB per capita, e como variável dependente, a taxa de crescimento do PIB per capita municipal. Evidenciou-se que alguns fatores potencializam o processo de crescimento econômico municipal, destaca-se o Capital Produtivo, que dentre as variáveis analisadas, desempenhou o principal papel positivo. Já o Capital Humano apresentou importância secundária, e o Capital Natural, praticamente não influenciou o crescimento. Os resultados também apontam que a espacialidade se mostrou fator extremamente importante para a economia paranaense, sugerindo que o desempenho econômico de uma determinada localidade, de modo geral, é influenciado diretamente pelo desempenho de seus vizinhos. Deve ser destacado também, que mesmo os municípios compartilhando de algumas características comuns, as idiossincrasias e potencialidades locais desempenharam papel fundamental para o crescimento destes. Em suma, as análises revelaram que as disparidades quanto à renda per capita apresentaram tendência de redução entre as economias municipais paranaenses, ou seja, dada a conjuntura estabelecida, ficou evidenciado a ocorrência do processo de convergência de renda per capita, tanto absoluta quanto condicional, demonstrando que o desenvolvimento econômico está tendendo a se disseminar pelos espaços geográficos estaduais. No entanto, estima-se que precisariam quase 59 anos para que as diferenças de renda per capita municipais atingissem a half-life, o que caracteriza a necessidade de políticas públicas voltadas à redução destas disparidades regionais, visto que a convergência mesmo tendendo a ocorrer, é bastante lenta entre os municípios paranaenses.
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Ensaios em desenvolvimento e crescimento econômicoRibeiro, Felipe Garcia 07 June 2013 (has links)
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Previous issue date: 2013-06-07 / This thesis consists of three essays, one being on economic development and the two others on economic growth. The first essay is an investigation into how access to electricity by households affects time allocation of children and teenagers from rural Brazil in what regards the choice to attend school or to engage in the labor market. To establish a causal relationship between the availability of electricity and time allocation, we use the criteria of priority works from Luz Para Todos program as a source of exogenous variation in access to electricity of households located in rural Brazil. We apply Regression Discontinuity Design and Difference in Difference estimator with endogenous variables. The results from the latter methodology indicate that the presence of electricity increases the likelihood that children and adolescents are enrolled in school and are not delayed relative to the grade they should be attending at their age. Also, the probability of a child being literate and not being working increases with the presence of electricity. One of the possible channels that could explain these results is the increased participation of mothers in the labor market. However, one cannot discard the hypothesis that the observed results are justified by the increased access to electricity by the schools, making them better and more attractive to students and by the receipt of Bolsa Familia program which is conditional on school attendence by children and teenagers. The second study aims to contribute to the literature on institutions and economic growth through the investigation of how the 1959 socialist revolution in Cuba have affected the trajectory of per capita income in that country. To do so, we apply the synthetic control method to obtain the counterfactual path of income per capita in the absence of such revolution. The results show that the trajectory of the annual GDP per capita of Cuba between 1959 to 1980 was lower than it would have been if the socialist regime had not been implemented. This result is robust to different placebo tests deployed and also to the use of different series of GDP per capita. Alternative hypotheses that could explain the lower path of GDP per capita are discussed based on the existing literature and data. The discussion suggests that institutional change was indeed the cause of the observed negative effect on the Cuban economy during the period of analysis. Finally, the third article investigates the economic cost of a natural disaster in Brazil. The paper looks at the excessive rains that happened in the state of Santa Catarina in November and December 2008. This study contributes with some new evidence to the iv recent literature on natural disasters. To our knowledge, there are no studies in Brazil that empirically measure the impact that a natural disaster has entailed on an affected region. This study is structured in two parts. The first uses synthetic control to measure the impact of rainfall on the industrial production of Santa Catarina. For that, we propose a small accommodation method for treating the effects of possible flooding rains in other states. In the second part, we use the method of difference in difference to measure the impact of the rains on the GDP per capita of the cities. The results show that for a period of two years after the end of 2008, the impact of the rains caused a lower monthly industrial production of 2.0% in Santa Catarina. For municipalities, the estimated effect of the disaster on GDP per capita was around -7.0% in 2008 and -5.0% in 2009. There was not significant effect in 2010. / Esta tese é composta por três ensaios, um na linha de desenvolvimento econômico e dois na linha de crescimento. O primeiro deles trata de uma investigação sobre o papel do acesso à energia elétrica a nível domiciliar na alocação do tempo das crianças e adolescentes do Brasil rural entre frequentar a escola e participar do mercado de trabalho. Para o estabelecimento da relação causal entre energia elétrica e a alocação de tempo se utilizam os critérios de prioridade de obras do programa Luz Para Todos como fonte de variação exógena no acesso à energia elétrica dos domicílios localizados na zona rural do Brasil. Aplicam-se os métodos de Regressão Descontínua e Diferenças em Diferenças com Variáveis Instrumentais. Os resultados obtidos da segunda metodologia apontam que a presença de energia elétrica aumenta a probabilidade das crianças e adolescentes estarem matriculadas na escola, não estarem atrasadas em relação à série que deveriam estar dada sua idade, serem alfabetizadas e não estarem trabalhando. Entre os possíveis canais capazes de explicar estes resultados está a maior participação das mães no mercado de trabalho. Entretanto, não se pode descartar a hipótese de que os resultados observados sejam justificados pelo aumento do aceso à energia elétrica a nível escolar, o que pode tornar as escolas melhores e mais atrativas, ou consequência do aumento do recebimento do programa Bolsa Família que exige frequência escolar das crianças e adolescentes. Já o segundo ensaio objetiva colaborar à literatura de instituições e crescimento econômico através da investigação do impacto da mudança institucional ocorrida em Cuba após a revolução socialista de 1959 sobre a trajetória da renda per capita do país. Para tanto, aplica-se o método de controle sintético para a obtenção do contrafactual da trajetória da renda per capita na ausência da revolução. Os resultados apontam que a trajetória do PIB per capita anual de Cuba entre 1959 a 1980 foi inferior ao que teria sido caso não tivesse sido implantado o regime socialista. Este resultado é robusto aos diferentes testes de placebo implantados e ao uso de distintas séries do PIB per capita de Cuba. Hipóteses alternativas à mudança institucional, mas também capazes de explicar a trajetória inferior do PIB per capita, são discutidas com base na literatura e na descrição de dados. A discussão sugere que foi de fato a mudança institucional a causa do efeito negativo observado sobre a economia cubana durante o período de análise. Por fim, o terceiro estudo investiga o custo econômico de um desastre natural ocorrido no Brasil em 2008, a saber, o excesso de chuvas em Santa Catarina entre os meses de novembro e dezembro daquele ano. Este artigo colabora com mais uma evidência para a recente literatura de desastres naturais. No Brasil não há nenhum trabalho, sob nosso conhecimento, medindo empiricamente o impacto que um desastre natural tenha acarretado a uma região atingida. Este estudo está estruturado em duas partes. Na primeira se utiliza o controle sintético para medir o impacto das chuvas na produção industrial de Santa Catarina. Propõe-se uma pequena acomodação do método para tratar o possível transbordamento dos efeitos das chuvas nos demais estados. Já na segunda parte, utiliza-se o método de diferenças em diferenças para medir o impacto das chuvas no PIB per capita das cidades mais atingidas. Os resultados apontam que para um período de dois anos após o final de 2008, o desastre causou uma produção industrial mensal 2.0% menor do que seria caso as chuvas não tivessem ocorrido. Por municípios, o efeito estimado do desastre sobre o PIB per capita se situou ao redor de -7,0% em 2008 e -5,0% em 2009. Em 2010 não há evidências de efeito.
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Produto interno bruto ajustado ambientalmente para Amazônia legal brasileira: uma análise de matriz de insumo-produto e matriz de contabilidade social / Environmental gross domestic product for Brazilian Legal Amazon: an analysis of input-output matrix and social accounting matrix.Andrea Castelo Branco Brasileiro 13 November 2012 (has links)
The purpose of this work was to present and apply an analytical tool to the flows of goods and income between economic agents and the environment that allows us to calculate the Environmental Gross Domestic Product (EGDP) for Brazilian Legal Amazon. In order to achieve this goal the Environmental Social Accounting Matrix (ESAM) was developed. The model was developed from the traditional Social Accounting Matrix, the Environmental Input-Output Analysis Models, and from the United Nations handbook on the System of Integrated Environmental and Economic Accountings. The EGDP was calculated from the Environmental Input-Output Analysis, since the unavailability of data did not allow the application of the model of ESAM. The flows between the economy and the environment considered were the emissions of green house gases (depreciation of natural capital) and the investment needed to return the air to the same quality it had before being polluted. The results showed that the inclusion of depreciation of natural capital in the Gross Domestic Product (GDP) and in the added value (AV) calculation for each industry of the Brazilian Legal Amazon Region diminished the AV significantly in the industries of cattle (235%), soybean (77%), and other activities of livestock and agricultural (24%). In the Rest of Brazil, the industries with the highest impact of depreciation of natural capital on AV were soybean (30%), cattle (15%) and sugarcane (13%). The total EGDP of the Brazilian Legal Amazon Region was 15% smaller than its total GDP, whereas this difference for the rest of Brazil was 1%. Considering that the GDP is a component of economic wellbeing, the results show a significant reduction in economic wellbeing due to green house gas emissions released into the air by economic activities, mainly due to land use changes. The Environmental Social Accounting Matrix Model is a useful tool to help decision makers since it offers an analytical instrument for economic behavior and the impacts of economic activities on the environment. / The purpose of this work was to present and apply an analytical tool to the flows of goods and income between economic agents and the environment that allows us to calculate the Environmental Gross Domestic Product (EGDP) for Brazilian Legal Amazon. In order to achieve this goal the Environmental Social Accounting Matrix (ESAM) was developed. The model was developed from the traditional Social Accounting Matrix, the Environmental Input-Output Analysis Models, and from the United Nations handbook on the System of Integrated Environmental and Economic Accountings. The EGDP was calculated from the Environmental Input-Output Analysis, since the unavailability of data did not allow the application of the model of ESAM. The flows between the economy and the environment considered were the emissions of green house gases (depreciation of natural capital) and the investment needed to return the air to the same quality it had before being polluted. The results showed that the inclusion of depreciation of natural capital in the Gross Domestic Product (GDP) and in the added value (AV) calculation for each industry of the Brazilian Legal Amazon Region diminished the AV significantly in the industries of cattle (235%), soybean (77%), and other activities of livestock and agricultural (24%). In the Rest of Brazil, the industries with the highest impact of depreciation of natural capital on AV were soybean (30%), cattle (15%) and sugarcane (13%). The total EGDP of the Brazilian Legal Amazon Region was 15% smaller than its total GDP, whereas this difference for the rest of Brazil was 1%. Considering that the GDP is a component of economic wellbeing, the results show a significant reduction in economic wellbeing due to green house gas emissions released into the air by economic activities, mainly due to land use changes. The Environmental Social Accounting Matrix Model is a useful tool to help decision makers since it offers an analytical instrument for economic behavior and the impacts of economic activities on the environment.
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Analyse discriminante et perceptron multicouche-liens formels et applicationsDiagne, Elhadji Diaraff Diegane January 2019 (has links) (PDF)
No description available.
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The economics of exchanging and adopting plant genetic resources for food and agriculture / Evidence from Germany and PeruLüttringhaus, Sophia 09 March 2022 (has links)
Landwirtschaftliche Systeme müssen sich immerfort an Druckfaktoren wie Klimawandel und Bevölkerungswachstum anpassen. Hierbei spielt die genetische Vielfalt von Pflanzen eine wichtige Rolle, da diese für die Sicherung der Ernährung und des Einkommens von entscheidender Bedeutung ist. Dennoch wird der wirtschaftliche Wert pflanzengenetischer Ressourcen selten untersucht. Um diese Forschungslücke zu schließen, werden in dieser Arbeit drei Bewertungen vorgestellt, welche die wirtschaftlichen Werte pflanzengenetischer Ressourcen untersuchen.
Im Rahmen dieser Dissertation werden zwei verschiedene Agrarsystemen analysiert. Diese unterscheiden sich hinsichtlich des Klimas, der agrarökologischen Bedingungen, der landwirtschaftlichen Praxis, der politischen und ökonomischen Rahmenbedingungen sowie der soziokulturellen Verankerung der Kulturart. Die ersten beiden Analysen befassen sich mit der Züchtung und Produktion von Winterweizen in Deutschland. Charakterisiert sind diese durch ein gemäßigtes Klima und intensive Anbaubedingungen. In diesem System überwiegen moderne Sorten, die in einem formalisierten Züchtungsprozess entstanden sind. Es werden die folgenden Forschungsfragen beantwortet: 1) Was ist der ökonomische Wert, der durch den Austausch von Zuchtmaterial entsteht? und 2) Wie hoch ist der mikroökonomische Wert von Resistenzzüchtung? In der dritten Analyse wird ein weiteres Agrarsystem vorgestellt: Die Andenlandwirtschaft, wo im Hochland unter extensiven Bedingungen eine Vielzahl von Kartoffellandrassen angebaut wird. Dort wird folgende Frage analysiert: 3) Welche Mehrwerte wurden durch die Repatriierung oder Neuverteilung von Kartoffellandrassen erzielt?
Diese Analysen zeigen, dass die Verfügbarkeit, der Austausch und die Nutzung von pflanzengenetischen Ressourcen die Agrarproduktion verbessern; es entstehen sowohl sektorale, mikroökonomische als auch ernährungsbezogene und kulturelle Mehrwerte. / Agricultural systems must constantly adapt to pressuring events such as climate change and population growth to maintain and improve production processes in a sustainable manner. Thereby the genetic diversity of plants used in agriculture constitute a strategic asset. Nevertheless, their economic value is often overlooked. To fill this research gap, this thesis presents three assessments that produce more evidence on the economic value of plant genetic resources.
Two very distinct agricultural systems are discussed. These differ greatly in terms of climate, agroecological conditions, farming practices, seed systems, political and economic frameworks, and the socio-cultural embeddedness of the crop in question. The first two assessments are concerned with winter wheat (Triticum aestivum) breeding and production in the temperate climate and intensive growing conditions in Germany. Modern cultivars created in a formalized breeding process prevail in this system. The following two research questions are elaborated: 1) What is the economic value of exchanging breeding material? and 2) What is the microeconomic value of resistance breeding? The third assessment presents a different agricultural system: Andean agriculture, where a wide variety of potato landraces (Solanum spp.) are grown extensively in the Peruvian highlands. In this case, the research question I investigated is: 3) What are the benefits of repatriating (i.e., redistributing) potato landraces to Andean farmers?
These studies demonstrate that the availability, exchange, and adoption of plant genetic resources, which are well adapted to and culturally embedded in specific agricultural systems, improve the overall quantity and sustainability of agricultural production. These improvements can be translated into sectoral, microeconomic as well as nutritional and cultural benefits.
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