Uma previsão de receitas precisa é muito importante para o administrador público na elaboração do orçamento anual, e para isso há a necessidade de se encontrar um modelo, econométrico ou não, que possibilite essa previsão com qualidade. Este trabalho apresenta uma forma inovadora para realizar a combinação de modelos de previsão. Seu objetivo foi criar uma metodologia para a obtenção de pesos para a combinação de modelos baseada no método de otimização de uma carteira de investimentos proposto por Markowitz. Para o estudo, foram utilizadas as estimações de três a cinco previsões individuais de um a cinco passos à frente, com os modelos Box-Jenkins SARIMA (Autorregressivo Integrado de Médias Móveis Sazonal), PLSR (Regressão com Mínimos Quadrados Parciais) e o Método não econométrico de Indicadores, como é denominado internamente na Receita Federal. A utilização da fronteira eficiente de Markowitz, que apresenta os pontos de mínima variância para cada retorno, é semelhante à minimização da variância da combinação, proposta no artigo seminal de Bates e Granger. O risco (desvio padrão), na teoria de portfólio de Markowitz, pode ser definido como a dispersão dos resultados e pode ser decomposto em risco sistemático e risco não sistemático. À medida que a quantidade de pesos das previsões a combinar cresce, a parte não sistemática do risco tende a zero, ficando o risco total representado somente pela parte sistemática. Por outro lado, observou-se que a curva de erros correspondente à fronteira eficiente apresenta quebras estruturais à medida que a quantidade de pesos não-zero varia. Selecionando-se trechos em que a quantidade de pesos é maior, minimiza-se a parte não sistemática, minimizando o erro. Dentro desses trechos selecionados, buscaram-se os pontos de menor erro, sendo a combinação encontrada chamada de Mínimo Erro Prim. O Mínimo Erro Seg foi o resultado da combinação com o menor erro, incluindo-se os trechos com a segunda maior quantidade de componentes diferentes de zero na combinação. Embora, na média, os pontos de Mínimo Erro Seg apresentem menor valor de erro que o Mínimo Erro Prim, como o segundo apresenta menor desvio padrão médio, optou-se pelo Mínimo Erro Prim para o ponto escolhido como a proposta de combinação deste estudo. Esse ponto apresenta resultados sistematicamente melhores que o da simples média, utilizada geralmente como benchmark. / A precise revenue forecast is very important for public administrators to draft an annual report. That is why there is a need to find a model, whether econometric or not, that makes it possible to have a quality forecast. This study proposes an innovative approach to executing a combination of forecasting models. The goal was to create a methodology to obtain weights in order to combine models based on the investment portfolio optimization method proposed by Markowitz. The estimates of three to five individual forecasts from one to five steps ahead were used for the study, with the Box-Jenkins SARIMA (Seasonal Autoregressive Integrated Moving Average) model, the PLSR (Partial Least Squares Regression) model and the non-econometric Method of Indicators, as it is called internally at the Brazilian Federal Revenue Service. The use of Markowitz\'s efficient frontier, which shows the points of minimum variance for each return, is similar to the minimization of the combination variance proposed in the seminal paper by Bates and Granger. The risk (standard deviation) in the Markowitz portfolio theory could be defined as a dispersion of results and could be broken down into systemic risk and non-systemic risk. Insofar as the amount of weights for the forecasts to be combined grows, the non-systemic part of the risks tends to move towards zero, with total risk only being represented by the systemic part. On the other hand, the error curve was found to correspond to the efficient frontier, showing structural breaks insofar as the amount of non-zero weights varies. By selecting parts where there is a greater amount of weights, the non-systemic part is minimized, thus minimizing error. Within these selected parts, the points of least error were sought, with the combination found being called the Prim Minimum Error. The Sec Minimum Error was the result of the combination with the lowest error, including the parts with the second highest amount of components different from zero in the combination. Although on average the Sec Minimum Error points show a lower error value than the Prim Minimum Error, since the second shows a lower standard deviation, the Prim Minimum Error was chosen as the point selected as the combination proposal of this study. This point shows systematically better results than the simple average generally used as a benchmark.

Orientador: Paulo de Barros Correia / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-19T21:23:58Z (GMT). No. of bitstreams: 1 Porto_NataliaAddas_M.pdf: 3278634 bytes, checksum: 844ae878f54ff582bbd8d0261e413863 (MD5) Previous issue date: 2012 / Resumo: A humanidade tem selecionado seus sistemas energéticos incorporando, além dos parâmetros de disponibilidade técnica e viabilidade econômica, os impactos ambientais causados por eles. O mercado de créditos de carbono surge neste contexto ao estabelecer mecanismos de mercado para que partes envolvidas na contribuição de redução/remoção de gases de efeito estufa na atmosfera, no âmbito do Protocolo de Quioto, cumpram o acordo quantificado, ao mesmo tempo em que surgem também novas oportunidades para investimentos nos países em desenvolvimento como o Brasil. Assim, saber como funciona esse mercado é um fator crucial para o aproveitamento das conveniências criadas pelo Protocolo de Quioto. Destarte, considerando as dificuldades para precificação de contratos de créditos carbono no mercado brasileiro, principalmente por ser um mercado muito recente, e ainda com o objetivo de originar maiores investimentos em sistemas energéticos através de energia renovável, a dissertação oferece uma contribuição situada nos seguintes focos: análise de contratos de Reduções Certificadas de Emissões (RCEs) e seleção de projetos do Mecanismo de Desenvolvimento Limpo (MDL). Precificação, portanto, compreende determinar medidas de benefício e risco unitário ¿/tCO2e), uma vez que as decisões de contratação são instruídas pelo preço da RCE negociado. O modelo de latisse binomial é a principal ferramenta de precificação empregada neste trabalho, usada para calcular o valor médio esperado da RCE para realização de contratos a termo e de opções. Por sua vez, melhores condições para o comércio das RCEs é obtida por uma abordagem da teoria do portfólio proposta por Markowitz, através de projetos MDL relacionados à produção de eletricidade a partir de fontes renováveis de energia no Brasil, onde a energia oferecida por tais fontes são caracterizadas, sobretudo, pela sazonalidade / Abstract: Humanity has selected energy systems by incorporating, beyond the technical and economic feasibility parameters, also the environmental impacts caused by them. The carbon credit market has appears in this context and brings alternative solutions for countries in Annex I to fulfill their emissions targets under Kyoto Protocol and also help developing countries in constructing or maintaining a clean energy mix. Knowing how this market works is crucial to incorporate all the conveniences brought by Kyoto Protocol. Pricing carbon credit market includes determining benefit and risk measures (¿/tCO2e), since the hiring decisions are instructed by the price of CERs traded. The binomial lattice model is the main tool used in this dissertation for pricing, which allow us to calculate the expected value of CERs for realization of forward and options contracts. Given that renewable energy sources are mainly characterized by seasonality, some sources can hedge others. In this sense, better conditions on trading CERs can be achieved through a portfolio theory approach proposed by Markowitz. Considering the difficulties for pricing carbon credits contracts on the Brazilian market, especially because of its recent characteristic, and with the aim of generating greater investments in the energy systems by using renewable energy sources, the present dissertation offers a contribution on: contract analysis applied to Certified Emission Reductions (CERs) and also on selecting projects from the Clean Development Mechanism (CDM). / Mestrado / Mestre em Planejamento de Sistemas Energéticos

The thesis focuses on the equity portfolio management with quantitative methods. We present 3 types of optimization objectives: One tries to find minimum variance portfolios, tangency portfolios and portfolios with maximized expected returns in the German stock market. It is possible to compare those investment opportunities with a market-cap weighted benchmark and an equal weighted portfolio. Expected returns of stocks are estimated with fundamental factor models. Risks of portfolios are estimated with 5 types of covariance matrices: the matrix calculated with historical returns, estimations with the single index model, Fama-French three factors model, fundamental factor model and the shrinkage method. Our results are doubled because of the demonstration of the impact of turnover constraint on portfolio performance measures (transaction costs are included in our calculations). One can see that optimized portfolios had attractive risk-return measures in the period 2005 - 2015. Benchmark and equal weighted portfolios were dominated and we consider them to be inefficient investments in our test.

We compare the performance of the perturbation-based (local) portfolio solution method of Devereux and Sutherland (2010a, 2011) with a global solution method. As a test suite we use model specifications that broadly capture features of international financial trade, between advanced economies, and between advanced and emerging economies. We consider both symmetric country setups and asymmetric setups, that capture important empirical facts such as differences in macroeconomic volatility, differences in portfolio composition, and high equity premia. We find that the local method performs well at business cycle frequencies, both in the symmetric and asymmetric settings, while significant differences arise at long horizons in asymmetric settings. (authors' abstract)

Formal art education equips students with skills to produce artworks. A formal art education may increase the opportunity for employment, however, art-related employment is very limited. Art graduates would be better equipped to market and manage art establishments or their own careers if art education were to be supplemented with basic business skills. Artists who wish to earn unsupplemented incomes from their art should undertake to acquire business acumen. This includes being presentable to the market place in attitude and appearance. It also includes aptitude in art, marketing and management. Role models and non-models of success and failure in business should also be observed. Art graduates should adopt applicable tried and tested business methods. Good marketing is a mix of business activities which identifies and creates consumer needs and wants. Marketing activities involve research, planning, packaging, pricing, promoting and distributing products and services to the public to create exchanges that satisfy individual and organisational objectives. Art products include artworks, frames, art books and art materials. Art-related services include the undertaking of commissions, consulting, teaching, free parking, convenient shopping hours, acceptance of mail or telephone orders, exhibitions, ease of contact, approval facilities, wrapping, delivery, installations (picture hanging), quotations, discounts, credit facilities, guarantees, trade-ins, adjustments and restorations. Good management is a mix of business activities which enables a venture to meet the challenges of supply and demand. There is a blueprint for management competence. The three dimensions of organisational competence are collaboration, commitment and creativity. Self-marketing and management is an expression of an artist's most creative being. It is that which can ensure and sustain recognition and income. Artists, like other competent organisations and entrepreneurs from the private sector, should operate with efficient manufacturing, marketing, management and finance departments. They are also equally important and therefore demand equal attention. Artistic skill together with business acumen should equip the artist to successfully compete in the market place. There are no short-cuts to becoming an artist but there are short-cuts to becoming a known and financially stable artist. Understanding marketing and management could mean the difference between waiting in poverty and frustration for a "lucky break" (which may only happen after an artists's death) and taking control. Success should be perpetuated through continuous effort.

Electricity transmission network investments are playing a key role in the integration process of power systems in the European Union. Given the magnitude of investment costs, their irreversibility, and their impact in the overall development of a region, accounting for the role of uncertainties as well as the involvement of multiple parties in the decision process allows for improved and more robust investment decisions. Even though the creation of this internal energy market requires attention to flexibility and strategic decision-making, existing literature and practitioners have not given proper attention to these topics. Using portfolios of real options, we present two stochastic mixed integer linear programming models for transmission network expansion planning. We study the importance of explicitly addressing uncertainties, the option to postpone decisions and other sources of flexibility in the design of transmission networks. In a case study based on the Azores archipelago we show how renewables penetration can increase by introducing contingency planning into the decision process considering generation capacity uncertainty. We also present a two-party Nash-Coase bargaining transmission capacity investment model. We illustrate optimal fair share cost allocation policies with a case study based on the Iberian market. Lastly, we develop a new model that considers both interconnection expansion planning under uncertainty and cross-border cost allocation based on portfolios of real options and Nash-Coase bargaining. The model is illustrated using Iberian transmission and market data.

Please read the abstract in the section 00front of this document / Thesis (PhD)--University of Pretoria, 2006. / Humanities Education / PhD / Unrestricted

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