A convertible bond (CB) is a hybrid security possessing the characteristics of both debt and equity. It gives the holder the right to convert the bond into a pre-specified number of shares (usually by the same issuer of the CB) until maturity of the bond, and may also contain additional features such as callability and putability. CB’s along with all hybrid securities are difficult to value due to their uncertain income stream. In this dissertation several convertible bond valuation models are suggested, but with particular attention to the calibration of the underlying inputs into the model and also by taking default risk into account, which is extremely important given the subordination of convertibles. The models range from the basic component models that decompose the CB into a straight bond and an exchange/call option; to more sophisticated ones consisting of stochastic interest rates, default risk, volatility structures, and even some exotics such as exchangeable and inflation-linked convertibles. An important aspect often missed by CB valuation models is the presence of negative convexity for extremely low share prices. As such a credit spread function dependent upon the underlying share price is introduced into the Tsiveriotis and Fernandes, and Hung and Wang models which improve upon the accuracy of the original models. Once a reliable model has been developed it becomes necessary to take advantage of convertible arbitrage trading strategies if they exist. The typical delta hedge, gamma hedge and option strategies that many convertible hedge funds employ are explained including the underlying risks with respect to the “Greeks”. Copyright / Dissertation (MSc)--University of Pretoria, 2009. / Mathematics and Applied Mathematics / unrestricted

[pt] Esta tese fornece uma revisão sistemática da literatura sobre a precificação de títulos corporativos ao redor do mundo. Estes títulos são mecanismos de financiamento essenciais para empresas do mundo inteiro e são primordiais para transferir recursos e fomentar o crescimento económico. O mercado de capitais é um mercado democrático e acessível, onde qualquer pessoa pode se tornar investidor, facilitando assim a criação de riqueza e dinamizando a economia. O processo de precificação de títulos de dívidas corporativas é o foco principal do trabalho, em que vai ser estudado quais são os fatores determinantes do preço desses títulos. Através de uma revisão sistemática da literatura, a pesquisa elucida relações complexas entre a precificação dos títulos, classificações de crédito, indicadores macroeconômicos e características específicas das emissões. A maior contribuição do presente estudo é uma tabela final que categoriza os fatores de determinação do preço em: corporativos, da emissão, de liquidez e macroeconômico/de mercado. Essa categorização é importante para servir de guia para trabalhos futuros. A literatura existente carece de revisões abrangentes sobre os fatores que influenciam os preços dos títulos corporativos de dívida e há uma notável ausência de categorizações destes fatores. / [en] This thesis provides a systematic literature review on the pricing of corporate bonds worldwide. These securities are essential financing mechanisms for companies worldwide and are vital to transfer resources and catalyze economic growth. The democratizing potential of capital markets is highlighted, emphasizing that anyone can become an investor, thus facilitating wealth creation and boosting the national economy. The main exploration of the study is the bond pricing process in financial markets, focusing on the determinants of the price of these securities. Through a systematic review of selected literature, the research elucidates complex relationships between bond valuation, credit ratings, macroeconomic indicators, and specific bond characteristics. The greatest contribution is a final table that categorize the factors into corporate, issuance, liquidity and macroeconomic/market. This categorization is important to serve as a guide for future works. The existing literature lacks comprehensive reviews on the factors influencing corporate bond prices, and there is a notable absence of categorizations of these factors.