Este trabalho apresenta uma metodologia de cálculo de sensibilidades utilizando equa- ções analíticas, levando em a conta a correção de smile na superfície de volatilidade, que não é contemplada no modelo de Black e Scholes. Dada a diferença signicativa na mensura ção do risco as instituições nanceiras calculam suas sensibilidades incorporando esta correção, mas tal determinação tem sido realizada por métodos numéricos, que acabam sendo mais lentos que a abordagem aqui proposta. São apresentadas equações analíticas para as principais sensibilidades do modelo a partir de dados de mercado usados na constução da superfície de volatilidade implícita. Ilustramos a comparação da técnica proposta com o método numérico com base no mercado de opções sobre taxa de câmbio Brasileiro. / This work presents a study on how we should adapted the Greeks or risk factors of the Black and Scholes model. We can derive analytical equations for the main sensitivities of the model and using the market data to build an implied volatility surface and to get additional terms for the risk factors. We propose to implement this model in a scheme of analytic differential equations derived from the pricing model and from the implied volatility function. The building of this implied volatility and risk factors was based on the foreign exchange Brazilian market.

[pt] Esta dissertação examina os impactos das boas práticas de governança corporativa na volatilidade dos retornos das ações dentro e fora de momentos de crise. Dados de freqüência diária foram utilizados para estimar modelos Autoregressivos Generalizados de Heterocedasticidade Condicional (GARCH) para quarenta e nove papéis negociados na Bolsa de Valores de São Paulo (BOVESPA). As evidências indicam um efeito negativo na maioria das séries analisadas. Para algumas ações, a redução da volatilidade é ainda maior em períodos de choques negativos. Foi encontrado, ainda, o resultado de que o risco mitigado é o idiossincrático e, desta forma, governança incentiva a manutenção da concentração de propriedade. / [en] This dissertation examines impacts of good practices of corporate governance on the volatility of returns in and out crisis periods. Daily data are used to estimate Generalized Autoregressive Conditional Heteroskedastic (GARCH) models for forty nine stocks traded on the São Paulo Stock Exchange (BOVESPA. It is found evidence of a negative impact on the majority of the analyzed series. For some stocks, the reduction of the volatility is even greater in crisis periods. It was also found that the risk mitigated is the idiosyncratic one and, thus, governance incentives the maintenance of ownership concentration.

We analyze the relation between volatility spillovers and jumps in financial markets. For this, we compared the volatility spillover index proposed by Diebold and Yilmaz (2009) with a global volatility component, estimated through a multivariate stochastic volatility model with jumps in the mean and in the conditional volatility. This model allows a direct dating of events that alter the global volatility structure, based on a permanent/transitory decomposition in the structure of returns and volatilities, and also the estimation of market risk measures. We conclude that the multivariate stochastic volatility model solves some limitations in the spillover index and can be a useful tool in measuring and managing risk in global financial markets. / Analisamos a relação existente entre spillovers e saltos na volatilidade nos mercados financeiros. Para isso, comparamos o índice de spillover de volatilidade proposto por Diebold and Yilmaz (2009), com um componente de volatilidade global, estimado através de um modelo multivariado de volatilidade estocástica com saltos na média e na volatilidade condicional. Este modelo permite uma datação direta dos eventos que alteram a estrutura de volatilidade global, baseando-se na decomposição das estruturas de retorno e volatilidade entre efeitos permanentes/transitórios, como também a estimação de medidas de risco de mercado. Concluímos que este modelo resolve algumas das limitações do índice de spillover além de fornecer um método prático para mensurar e administrar o risco nos mercados financeiros globais.

Como a volatilidade é a única variável não observada nas fórmulas padrão de apreçamento de opções, o mercado financeiro utiliza amplamente o conceito de volatilidade implícita, isto é, a volatilidade que ao ser aplicada na fórmula de apreçamento resulte no preço correto (observado) das opções negociadas. Por isso, entender como as volatilidades implícitas das diversas opções de dólar negociadas na BM&F, o objeto de nosso estudo, variam ao longo do tempo e como estas se relacionam é importante para a análise de risco de carteiras de opções de dólar/real bem como para o apreçamento de derivativos cambiais exóticos ou pouco líquidos. A proposta de nosso estudo é, portanto, verificar se as observações da literatura técnica em diversos mercados também são válidas para as opções de dólar negociadas na BM&F: que as volatilidades implícitas não são constantes e que há uma relação entre as variações das volatilidades implícitas e as variações do valor do ativo objeto. Para alcançar este objetivo, aplicaremos a análise de componentes principais em nosso estudo. Com esta metodologia, reduziremos as variáveis aleatórias que representam o processo das volatilidades implícitas em um número menor de variáveis ortogonais, facilitando a análise dos dados obtidos. / Volatility is the only unobserved variable in the standard option pricing formulas and hence implied volatility is a concept widely adopted by the financial market, meaning the volatility which would make the formula yield the options real market price. Therefore, understanding how the implied volatility of the options on dollar traded at BM&F, the subject of our study, vary over time is important for risk analysis over dollar option books and for pricing of exotic or illiquid derivatives Our works proposal is to verify if the observations made by the technical literature over several markets could also be applied to the options on dollar traded at BM&F: implied volatilities do vary over time and there is a relation between this variation and the variation of the underlying asset price. In order to fulfill these goals, we will apply principal component analysis in our study. This methodology will help us analyze the data by reducing the number of variables that represent the implied volatility process into a few orthogonal variables.

O objetivo desta tese consiste na elaboração de dois estudos empíricos. No primeiro, estuda-se as propriedades da estrutura a termo das taxas de juros e em particular testa-se a validade da hipótese de expectativas a dados brasileiros e americanos. Os melhores resultados foram obtidos para os dados americanos. No segundo estudo pesquisa-se os determinantes da volatilidade dos títulos de dívida soberana de quatro países – Brasil, Argentina, Rússia e México. Os modelos utilizados são multivariados da família GARCH. Avalia-se em que medida as crises financeiras pelas quais passaram os países citados implicaram em algum tipo de contágio aos demais. Há evidência favorável à hipótese de contágio de muitos dos eventos estudados. / The thesis is composed by two empirical studies. In the first it’s analyzed the proprieties of the interest rate term structure and, in particular, it’s investigated whether or not the expectation hypothesis is a good description of Brazilian and American data. The results are better for American data. In the second study it’s investigated the sovereign debt bonds volatility of four countries – Brazil, Mexico, Russia and Argentine. The volatility was analyzed by the estimation of multivariate GARCH models. The existence of financial crises contagion was investigated and tested. There is some evidence in favor of the contagion hypothesis.

A oferta de bens e serviços para atendimento da demanda dos consumidores atuais tem uma forte base na personalização, ou seja, na busca da satisfação individual dos clientes. Essa tem sido a forma que as empresas tem encontrado para se diferenciar. Para tanto, as organizações necessitam de modelos de negócios que permitam ajustar seus processos com as freqüentes necessidades de mudanças. A metodologia utilizada foi a observação de estudo de casos com projetos de Inovação Tecnológica, que possuem altos índices na característica de mudança dos requisitos. A proposta deste trabalho é permitir que essa volatilidade seja identificada na fase de eliciação de requisitos, com base nas intenções de cada envolvido no processo de engenharia de requisitos, e que tais solicitações possam ser melhor compreendidas através da prototipação baseada nas perspectivas dos participantes: de negócio, operacional, de design e gerencial. Como resultado foi definido o volaRE, que permite se conhecer a volatilidade de um requisito, com base nas características definidas do mesmo, ainda na fase de eliciação. / Current consumers have demanded a special attention in the production and distribution of goods and services which have turned organizations to mass customization, looking for an individual satisfaction of their customers. This has been the form that companies have found to differentiate themselves. Therefore, the integration of business and productive processes must be adaptable to the frequent changes in the company\'s environment. The used methodology was the observation of cases study with of Technological Innovation projects, which have high rates of requirements changes. The proposal of this work is that this volatility could be identified in the requirements elicitation phase, based on the intent of each involved in the process of requirements engineering, and that such requests can be better understood through perspectives prototyping based of those participants: business, operational, design and management. As result volaRE was defined, that lets to know the requirement\'s volatility, based on defined characteristics, yet at elicitation phase.

This thesis presents three empirical chapters investigating the informativeness of aggregate insider trading activities in the UK’s stock and option markets. Chapter one examines the relationship between aggregate insider trading and stock market volatility. The results suggest a positive relationship between aggregate insider trading and stock market volatility, confirming the hypothesis that aggregate insider trading increases the rate of flow of information into the stock market which in turn increases stock market volatility. Given that insiders also trade for non-informational reasons, we distinguish between informative and noisy insider trades and examine whether they affect stock market volatility differently. We find that only aggregate insider buy trades and medium sized insider trades affect stock market volatility positively. Chapter two re-examines whether aggregate insider trading can help predict future UK stock market returns. The results suggest that there is information in aggregate insider trading that can help predict future stock market returns. This is due to aggregate insiders’ ability to time the market based on their possession of superior information about unexpected economy-wide changes. We also find that a positive shock in aggregate insider trading causes an increase in future stock market returns two months after the shock. We test whether there is information in medium insider trades that can help predict future stock market returns. The results suggest that medium insider trades, specifically medium insider buy trades can help predict future stock market returns. Lastly, chapter three explores the relationship between aggregate exercise of executive stock options (ESO) and stock market volatility. Insiders in possession of private information may use their informational advantage to trade in the option markets via their exercise of ESOs which may affect stock market volatility. We find that aggregate exercise of ESOs affect stock market volatility positively. This is due to an increase in the rate of flow of information released via private information motivated exercises which cause prices to move as they adjust to the new information thereby increasing volatility. When executives have private information about future stock performance, they are motivated to exercise and sell stocks post exercise to avoid losses. They are also motivated to exercise and sell only a proportion of their stocks, specifically more than 50% of the acquired stocks and they exercise near the money ESOs. We find that for all these private information motivated reasons to exercise ESOs, stock market volatility is positively affected.

This thesis deals with the application of stochastic claims reserving methods to given data with some trends in claims development. It describes the chain ladder method and the generalized linear models as its stochastic framework. Some simple functions are suggested for smoothing the origin and development period coefficients from the estimated model. The extrapolation is also considered for estimation of the unobserved tail values. The residual bootstrap is used for the reparameterized model in order to get the predictive distribution of the estimated reserve together with its standard deviation as a measure of volatility. Solvency capital requirement in one year time horizon is also calculated. 1

Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2015-06-26T17:56:20Z No. of bitstreams: 1 CleiaDuarteMachado.pdf: 663088 bytes, checksum: dee11069e4c8adc0f1abe00e964f5b4c (MD5) / Made available in DSpace on 2015-06-26T17:56:20Z (GMT). No. of bitstreams: 1 CleiaDuarteMachado.pdf: 663088 bytes, checksum: dee11069e4c8adc0f1abe00e964f5b4c (MD5) Previous issue date: 2011-06-30 / Banco Santander / Banespa / O presente estudo analisa a volatilidade da Bolsa de Valores para os países do BRIC entre janeiro de 2005 a março de 2010. A pesquisa tem a finalidade de verificar a existência do efeito contágio entre esses emergentes. Foram utilizados diversos modelos de volatilidade determinística da família GARCH, tanto univariado, quanto multivariado. Também foi investigado até que ponto a crise financeira de 2008 resultou em mudanças na relação entre esses países. Para tanto, foram feitas estimativas para o período pré e pós 2008. Os resultados sinalizaram a existência de diversos fatos estilizados na volatilidade da bolsa de valores, como assimetria, aglomeração e efeito leverage. Porém, não foi possível aceitar a hipótese de efeito contágio, apesar de os valores encontrados para correlação para o período de pós crise serem superiores aos calculados para o período que a antecede. Sendo assim, ao investir em ativos nos países do BRIC os investidores internacionais conseguem diversificar riscos. / This study examines the volatility of the stock exchange for the BRIC countries from January 2005 to March 2010. The research aims to verify the existence of the contagion effect between these emerging markets. We used several models of deterministic GARCH volatility, both univariate and multivariate. We also investigated the extent to which the financial crisis of 2008 resulted in changes in the relationship between these countries. To this end, estimates were made for the period before and after 2008. The results showed the existence of several stylized facts of volatility in the stock market, as asymmetry, clustering and leverage effect. However, we could not accept the contagion effect hypothesis, although the values found for correlation to the post crisis period are higher than those calculated for the period that precedes it. Thus, by investing in assets in BRIC countries international investors can diversify risks.

Philosophiae Doctor - PhD (Economics) / The main objective of this thesis was to closely examine several nancial and economic aspects of the stock markets in Sub-Saharan Africa. Thus, the objectives of this thesis were to explore the interdependence, the time-varying conditional correlation and the volatility linkages among Sub-Saharan African and developed stock markets; to investigate the relationship between - nancial liberalization and the development of stock markets; and to examine the patterns of the aggregate market liquidity and the relevance of the mainstream determinants of market liquidity in the chosen Sub-Saharan African stock markets. The study was composed of three standalone essays. The rst essay, which investigated stock price co-movements and the volatility linkages between selected Sub-Saharan African markets and the key developed markets, used the Johansen cointegration test, the VECM and the GARCH models for the sample period 2 January 2009 { 31 December 2016. The second essay, examining the e ect of nancial liberalization on the development of stock markets in Sub-Saharan Africa, employed the Bayesian VAR for the sample period 1975Q1 { 2014Q4. Lastly, the third essay, which investigated the determinants of liquidity levels in Sub-Saharan African stock markets employed the Markov Switching Vector Autoregressive model for the sample period 2 January 2009 { 31 December 2016.This study aimed at contributing to the already existing literature by focusing on analysing four key stock markets in the region, namely the Nigerian Stock Exchange, the Kenyan Securities Exchange.