This dissertation is comprised of two papers. The first paper (Chapter 1) provides the theoretical foundation for the estimation of systematic downside risk. Using a new approach, I derive a measure of downside systematic risk, downside beta, that is free of the endogeneity problem and thus straightforward to calculate. Since there is no consensus in the literature regarding the appropriate method for the estimation of downside beta, I review the alternative specifications proposed in the past. I explicitly show that the derived formula here is more efficient in capturing downside risk on both theoretical grounds and in terms of empirical results. Using this efficient specification of systematic downside risk, I show that downside beta has increased explanatory power towards the cross-section of equity returns as compared to unconditional beta. In particular, downside beta predicts larger and more significant future premia, insignificant intercepts in portfolio cross-section tests and cannot be subsumed by additional risk factors proposed in the past literature. I attribute this superior performance to the ability of downside risk to capture distress risk and to the fact that it does not penalize (reward) good (bad) events in good states. In the second paper (Chapter 2) that is co-authored with my advisor, Gregory Kadlec, we exploit the notion of downside risk to explain a long-withstanding market anomaly; the long-term stock return reversals. We show that downside betas of past losers are significantly greater than downside betas of past winners, and the inclusion of downside beta in Fama-Macbeth regressions subsumes the reversal effect. / Ph. D.

O trabalho tem como objetivo identificar a existência do efeito momento, de comprar ações com alto desempenho relativo no passado e vender as de baixo desempenho relativo no passado, e do efeito contrário, de comprar ações com baixo desempenho relativo no passado e vender as de alto desempenho relativo no passado. A análise considerou 662 ações negociadas na BM&FBOVESPA entre julho de 1994 e junho de 2015, considerando quatro períodos de formação (3, 6, 9 e 12 meses) e seis de manutenção (3, 6, 9 e 12, 18 e 24 meses) das carteiras. A metodologia adotada para o efeito momento utiliza a abordagem de Jegadeesh e Titman (1993) e, para o efeito contrário, optou-se por De Bondt e Thaler (1985). A partir da identificação das carteiras vencedoras e perdedoras, passou-se a calcular as diferenças dos retornos acumulados mensais com uma janela móvel para expurgar o viés de seleção. Das 24 estratégias analisadas, verificou-se que apenas uma não apresentou significância para o efeito momento e rejeitou-se a hipótese de existência do efeito contrário. Constatou-se o efeito momento em 23 estratégias, sendo que duas apresentaram desempenho médio mensal superior ao Ibovespa no mesmo período, nas carteiras \"12x3\" e \"9x6\", respectivamente, de 1,60% e 1,48%. As principais contribuições do trabalho foram a adoção de uma carteira móvel para a avaliação do desempenho das carteiras, o amplo período utilizado na análise e o grande número de ativos, o que proporciona maior robustez aos resultados encontrados. / The work aims to find momentum effect, that buys stocks with relative high return in the past and sells stocks with relative poor return in the past, and the contrarian effect, that buys stocks with relative poor return in the past and sells stocks with relative high performance in the past. The analysis included 662 stocks traded on BM&FBOVESPA between July 1994 and June 2015, considering four formation periods (3, 6, 9 and 12 months) and six holding periods (3, 6, 9 and 12, 18 and 24 months) for the portfolios. The methodology adopted for momentum effect uses the theory of Jegadeesh and Titman (1993) and the contrarian effect uses De Bondt and Thaler (1985) theory. From the identification of winners\' portfolios and losers\' portfolios, it was calculated the differences in monthly cumulative returns with a rolling window to purge the selection bias. Of the 24 strategies analyzed, it was found that only one has no significance for momentum effect, and the hypothesis of contrarian effect was rejected. Momentum effect was found in 23 strategies, and two had average monthly performance superior to Ibovespa in the same period in the \"12x3\" portfolios and \"9x6\" portfolios, respectively, 1.60% and 1.48%. The main contributions of this study was to adopt a rolling window for evaluating the performance of the portfolios, the extended period used in the analysis and the large number of stocks, which provides greater robustness to the results found

O trabalho tem como objetivo identificar a existência do efeito momento, de comprar ações com alto desempenho relativo no passado e vender as de baixo desempenho relativo no passado, e do efeito contrário, de comprar ações com baixo desempenho relativo no passado e vender as de alto desempenho relativo no passado. A análise considerou 662 ações negociadas na BM&FBOVESPA entre julho de 1994 e junho de 2015, considerando quatro períodos de formação (3, 6, 9 e 12 meses) e seis de manutenção (3, 6, 9 e 12, 18 e 24 meses) das carteiras. A metodologia adotada para o efeito momento utiliza a abordagem de Jegadeesh e Titman (1993) e, para o efeito contrário, optou-se por De Bondt e Thaler (1985). A partir da identificação das carteiras vencedoras e perdedoras, passou-se a calcular as diferenças dos retornos acumulados mensais com uma janela móvel para expurgar o viés de seleção. Das 24 estratégias analisadas, verificou-se que apenas uma não apresentou significância para o efeito momento e rejeitou-se a hipótese de existência do efeito contrário. Constatou-se o efeito momento em 23 estratégias, sendo que duas apresentaram desempenho médio mensal superior ao Ibovespa no mesmo período, nas carteiras \"12x3\" e \"9x6\", respectivamente, de 1,60% e 1,48%. As principais contribuições do trabalho foram a adoção de uma carteira móvel para a avaliação do desempenho das carteiras, o amplo período utilizado na análise e o grande número de ativos, o que proporciona maior robustez aos resultados encontrados. / The work aims to find momentum effect, that buys stocks with relative high return in the past and sells stocks with relative poor return in the past, and the contrarian effect, that buys stocks with relative poor return in the past and sells stocks with relative high performance in the past. The analysis included 662 stocks traded on BM&FBOVESPA between July 1994 and June 2015, considering four formation periods (3, 6, 9 and 12 months) and six holding periods (3, 6, 9 and 12, 18 and 24 months) for the portfolios. The methodology adopted for momentum effect uses the theory of Jegadeesh and Titman (1993) and the contrarian effect uses De Bondt and Thaler (1985) theory. From the identification of winners\' portfolios and losers\' portfolios, it was calculated the differences in monthly cumulative returns with a rolling window to purge the selection bias. Of the 24 strategies analyzed, it was found that only one has no significance for momentum effect, and the hypothesis of contrarian effect was rejected. Momentum effect was found in 23 strategies, and two had average monthly performance superior to Ibovespa in the same period in the \"12x3\" portfolios and \"9x6\" portfolios, respectively, 1.60% and 1.48%. The main contributions of this study was to adopt a rolling window for evaluating the performance of the portfolios, the extended period used in the analysis and the large number of stocks, which provides greater robustness to the results found

This study employs a quantitative approach to investigate the momentum phenomenon in the commodity futures market. The study captures the phenomenon using two momentum indicators, namely, MACD and RSI, and extends the scope of indicator utilization to both joint and single usage. The research aims to explore whether portfolios consisting of these indicators can generate abnormal returns in the commodity futures market, in comparison to the S&P GSCI, which was used as the benchmark index. The study uses accumulated data from 2010 to 2019, with portfolios constructed on a quarterly basis. Statistical significance determination is executed by exporting the data to Stata, where the normality distribution is ascertained using the Shapiro-Wilk test. This was later followed by t-tests in order to dictate statistical significance on each portfolio compared to the S&P GSCI. The study reveals empirical evidence to support two of the three strategies, namely, the joint use of the aforementioned momentum indicators and single use of the RSI momentum indicator. However, the accumulated yield of the portfolio provided insufficient results to conclude the statistical significance of the single use of the MACD momentum indicator. The authors derive these results and observed phenomena from several financial theories, which are divided into three main sections in the theoretical framework, including information-based, risk-based, and behavior-based explanations. Relevant theories are included to support the research at hand. Furthermore, the authors incorporate the Efficient Market Hypothesis (EMH) under the pretense of challenging its view on efficient markets. They do so by constructing portfolios which yield abnormal returns and subsequently question the notion of efficient markets. The authors deduct that their findings produce some evidence to support the absence of strong form and semi-strong form of market efficiency in the commodity futures market. Overall, this study provides valuable insights into the momentum phenomenon in the commodity futures market and different incorporating investment techniques in which they are utilized. The ways in which momentum strategies can be utilized and momentum indicators interpreted, as displayed in this thesis, presents practical implications for investors and financial professionals.