Submitted by José Augusto Mazzoni Martins Ferreira (josemazzoni@bancobbm.com.br) on 2017-11-01T19:45:43Z No. of bitstreams: 1 Dissertacao - José Mazzoni (versão final).pdf: 1837578 bytes, checksum: 7e30e5efce6e72b928dccfb012c11a50 (MD5) / Approved for entry into archive by Marcia Bacha (marcia.bacha@fgv.br) on 2017-11-29T13:53:47Z (GMT) No. of bitstreams: 1 Dissertacao - José Mazzoni (versão final).pdf: 1837578 bytes, checksum: 7e30e5efce6e72b928dccfb012c11a50 (MD5) / Made available in DSpace on 2017-11-29T13:54:08Z (GMT). No. of bitstreams: 1 Dissertacao - José Mazzoni (versão final).pdf: 1837578 bytes, checksum: 7e30e5efce6e72b928dccfb012c11a50 (MD5) Previous issue date: 2017-01-24 / This work evaluates the regulatory capital required by Brazilian Central Bank (“BCB”) from financial institutions under its regulation, concerning the standard approach for marked risk, compared to alternative approaches commonly used by the financial industry, equivalent to VaR and Stress-Testing models. For a chosen group of risky assets (foreign currencies, stocks, stock indexes, commodities and interest rates), it was calculated the regulatory capital required by BCB under standard approach and compared to the estimated potential losses, according the alternative models. The results evidence a conservative position by BCB related to market risk of foreign currencies and interest rates, being more suitable for commodities and lenient for equities and their respective indexes. It is also possible to observe the existence of regulatory arbitrage, in which there is very low regulatory capital requirement (or no requirement) for certain risky assets portfolios. / Esse trabalho avalia o capital requerido pelo Banco Central do Brasil (“BCB”) das instituições financeiras por ele reguladas, para risco de mercado segundo abordagem padronizada, em comparação com métricas comumente adotadas pela indústria financeira, referentes aos modelos de VaR e Stress-Testing. Para um determinado grupo escolhido de ativos arriscados (moedas, ações, índice de ações, commodities e taxas de juros), foi aplicada a abordagem do BCB para o capital regulatório requerido e comparada com a perda potencial estimada pelos modelos alternativos. Os resultados evidenciam uma postura bastante conservadora por parte do BCB em relação aos riscos de mercado de moedas e taxas de juros, sendo mais ponderada para commodities e leniente para ações e seus respectivos índices. Pode-se também avaliar a existência de arbitragens regulatórias, onde há exigência muito baixa de capital regulatório (ou nenhuma exigência) para determinados portfólios arriscados.

This thesis consists of four independent chapters on bank capital regulation and the issue of unsolicited ratings.<p><p>The first chapter is introductory and reviews the motivation for regulating banks and credit rating agencies while providing a detailed overview of the thesis.<p><p>The second chapter uses a simultaneous equations model to analyze how banks from six G10 countries adjusted their capital to assets ratios and risk-weighted assets to assets ratio between 1988 and 1995, i.e. just after passage of the 1988 Basel Accord. The results suggest that regulatory pressure brought about by the 1988 capital standards had little effect on both ratios for weakly capitalized banks, except in the US. In addition, the relation between the capital to assets ratios and the risk-weighted assets to assets ratio appears to depend not only on the level of capitalization of banks, but also on the countries or groups of countries considered.<p><p>The third chapter provides Monte Carlo estimates of the amount of regulatory capital that EMU banks must hold for their corporate, bank, and sovereign exposures both under Basel I and the standardized approach to credit risk in Basel II. In the latter case, Monte Carlo estimates are presented for different combinations of external credit assessment institutions (ECAIs) that banks may choose to risk weight their exposures. Three main results emerge from the analysis. First, although the use of different ECAIs leads to significant differences in minimum capital requirements, these differences never exceed, on average, 10% of EMU banks’ capital requirements for corporate, bank, and sovereign exposures. Second, the standardized approach to credit risk provides a small regulatory capital incentive for banks to use several ECAIs to risk weight their exposures. Third, the minimum capital requirements for the corporate, bank, and sovereign exposures of EMU banks will be higher in Basel II than in Basel I. I also show that the incentive for banks to engage in regulatory arbitrage in the standardized approach to credit risk is limited.<p><p>The fourth and final chapter analyses the effect of soliciting a rating on the rating outcome of banks. Using a sample of Asian banks rated by Fitch Ratings, I find evidence that unsolicited ratings tend to be lower than solicited ones, after accounting for differences in observed bank characteristics. This downward bias does not seem to be explained by the fact that better-quality banks self-select into the solicited group. Rather, unsolicited ratings appear to be lower because they are based on public information. As a result, they tend to be more conservative than solicited ratings, which incorporate both public and non-public information.<p> / Doctorat en sciences économiques, Orientation économie / info:eu-repo/semantics/nonPublished

Este trabalho consiste em um estudo comparativo de diversos modelos para cálculo do Valor em Risco de um portifólio. São comparados modelos que consideram a série univariada de log-retornos do portifólio versus mo- delos multivariados, que consideram as séries de log-retornos de cada ativo que compõe o portifólio e suas correlações condicionais. Além disso, são testados modelo propostos recentemente, que possuem pouca literatura a respeito, como o PS-GARCH e o VARMA-GARCH. Também propomos um novo modelo, que utiliza o resultado acumulado do portifólio nos últimos dias como variável exógena. Os diferentes modelos são avaliados em termos de sua adequação às exigëncias do Acordo de Basileia e seu impacto financeiro, em um período que inclui épocas de alta volatilidade. De forma geral, não foram notadas grandes diferenças de performance entre modelos univariados e multivariados. Os modelos mais complexos mostraram-se mais eficientes, produzindo resultados satisfatórios inclusive em tempos de crise. / The present work consists of a comparative study of several portfolio Value-at-Risk models. Univariate models, which consider only the portfolio log-returns series, are compared to multivariate models, which consider the log-returns series of each asset individually and their conditional correlations. Additionally, recently proposed models such as PS-GARCH and VARMA-GARCH are tested. We also propose a new model that uses past cumulative returns as exogenous variables. All models are evaluated in terms of their compliance to Basel Accord and financial impact, in period that includes high volatility times. In general, univariate and multivariate models performed similarly. More complex models yielded more accurate results, with satisfactory performance including in crisis periods.

Este trabalho consiste em um estudo comparativo de diversos modelos para cálculo do Valor em Risco de um portifólio. São comparados modelos que consideram a série univariada de log-retornos do portifólio versus mo- delos multivariados, que consideram as séries de log-retornos de cada ativo que compõe o portifólio e suas correlações condicionais. Além disso, são testados modelo propostos recentemente, que possuem pouca literatura a respeito, como o PS-GARCH e o VARMA-GARCH. Também propomos um novo modelo, que utiliza o resultado acumulado do portifólio nos últimos dias como variável exógena. Os diferentes modelos são avaliados em termos de sua adequação às exigëncias do Acordo de Basileia e seu impacto financeiro, em um período que inclui épocas de alta volatilidade. De forma geral, não foram notadas grandes diferenças de performance entre modelos univariados e multivariados. Os modelos mais complexos mostraram-se mais eficientes, produzindo resultados satisfatórios inclusive em tempos de crise. / The present work consists of a comparative study of several portfolio Value-at-Risk models. Univariate models, which consider only the portfolio log-returns series, are compared to multivariate models, which consider the log-returns series of each asset individually and their conditional correlations. Additionally, recently proposed models such as PS-GARCH and VARMA-GARCH are tested. We also propose a new model that uses past cumulative returns as exogenous variables. All models are evaluated in terms of their compliance to Basel Accord and financial impact, in period that includes high volatility times. In general, univariate and multivariate models performed similarly. More complex models yielded more accurate results, with satisfactory performance including in crisis periods.

Made available in DSpace on 2016-06-02T20:06:09Z (GMT). No. of bitstreams: 1 5762.pdf: 2315381 bytes, checksum: 2d23013b02c4b33dcbf1b10405b613b9 (MD5) Previous issue date: 2014-02-12 / Financiadora de Estudos e Projetos / In this work, we present and discuss the operational risk in the financial institutions, Basel Accord II, the structure of dependence between cumulative operational losses, a tool for modeling this dependence (theory of copula) and the allocation of a capital, called regulatory capital. The usual method for calculation of regulatory capital for operational risk, suggested by Basel Committee, overestimates the final capital because it is considered that the losses are perfectly positively dependents. Then, we propose a new method for this calculation based on theory of copula for the bivariate case. Such method models the dependence between two losses and considers a index (representing the expert opinion). We discuss also a method studied on Alexander (2003) and perform a simulation study in order to compare all methods, the usual, the proposed and the convolution one. / Nesse trabalho, abordamos o risco operacional nas instituições financeiras sob o ponto de vista do Acordo de Basileia II, a característica da presença de dependência estocástica entre as variáveis aleatórias em questão, a ferramenta para modelagem de tal dependência (teoria de cópulas) e a alocação de capital regulatório. Como o método usual para alocação de capital regulatório sugerido pelo Acordo de Basileia II superestima tal capital por considerar que as variáveis perdas são perfeitamente dependentes, propomos neste trabalho uma metodologia alternativa, baseada em teoria de cópulas, para o caso bivariado. Tal metodologia modela a dependência entre duas perdas e ainda inclui a opinião de especialistas da área no modelo final. Também discutimos uma metodologia existente na literatura (método da convolução) e fazemos um estudo de simulação para analisar o comportamento dos métodos abordados: método usual, proposto e da convolução.