Momentum is one of the most robust anomalies in financial markets, there are two main recent explanations for this phenomenon, a behavioral-based explanation through disposition-effect (i.e., the willingness to sell \"winners\" too quickly and to hold \"losers\" for a long time) and a fund-flow based explanation. The disposition-effect explanation is centered in the convergence of the spread between the fundamental value and the observed market price (disposition-effect causes an underreaction to news that generates this spread), and the fund flows-based explanation is due to the persistence of the performance of mutual-funds (which usually keep buying winning positions and selling the losses). This master thesis compares those theories using Brazilian data (which is suitable for the strong presence of momentum). Our empirical analysis was done using Fama-MacBeth regressions with results pointing the disposition-effect explanation as the most significant, with our robustness analysis contributing positively to the main findings. / Uma das anomalias mais robustas presente nos mercados financeiros é a existência de momentum nos preços de ações, existem duas principais explicações recentes para este fenômeno: explicação comportamental através do efeito-disposição (i.e. disposição de vender ativos \"vencedores\" rapidamente e de segurar ativos \"perdedores\" por muito tempo) e explicações de fluxos de fundos de investimento. A explicação através do efeito-disposição é centrada na convergência do spread entre o valor fundamental de um ativo e o preço de mercado observado (o efeito-disposição causa uma reação branda a notícias que gera esse spread), e a explicação baseada em fluxos de fundos que se deve pela persistência da performance de fundos (que usualmente continuam comprando posições vencedoras e vendendo as perdedoras). O objetivo desta dissertação é comparar essas teorias utilizando dados brasileiros (que é adequado pela forte presença de momentum). Nossa análise empírica foi feita através de regressões de Fama-MacBeth com resultados apontando a explicação centrada no efeito-disposição como a mais significativa, com nossa análise de robustez contribuindo positivamente para nossos resultados principais.

This thesis studies the use of nonparametric econometric methods to reconcile the empirical behaviour of financial asset prices with theoretical valuation models. The confrontation of economic theory with asset price data requires various functional form assumptions about the preferences and beliefs of investors. Nonparametric methods provide a flexible class of models that can prevent misspecification of agents’ utility functions or the distribution of asset returns. Evidence for potential nonlinearity is seen in the presence of non-Gaussian distributions and excessive volatility of stock returns, or non-monotonic stochastic discount factors in option prices. More robust model specifications are therefore likely to contribute to risk management and return predictability, and lend credibility to economists’ assertions. Each of the chapters in this thesis relaxes certain functional form assumptions that seem most important for understanding certain asset price data. Chapter 1 focuses on the state-price density in option prices, which confounds the nonlinearity in both the preferences and the beliefs of investors. To understand both sources of nonlinearity in equity prices, Chapter 2 introduces a semiparametric generalization of the standard representative agent consumption-based asset pricing model. Chapter 3 returns to option prices to understand the relative importance of changes in the distribution of returns and in the shape of the pricing kernel. More specifically, Chapter 1 studies the use of noisy high-frequency data to estimate the time-varying state-price density implicit in European option prices. A dynamic kernel estimator of the conditional pricing function and its derivatives is proposed that can be used for model-free risk measurement. Infill asymptotic theory is derived that applies when the pricing function is either smoothly varying or driven by diffusive state variables. Trading times and moneyness levels are modelled by marked point processes to capture intraday trading patterns. A simulation study investigates the performance of the estimator using an iterated plug-in bandwidth in various scenarios. Empirical results using S&P 500 E-mini European option quotes finds significant time-variation at intraday frequencies. An application towards delta- and minimum variance-hedging further illustrates the use of the estimator. Chapter 2 proposes a semiparametric asset pricing model to measure how consumption and dividend policies depend on unobserved state variables, such as economic uncertainty and risk aversion. Under a flexible specification of the stochastic discount factor, the state variables are recovered from cross-sections of asset prices and volatility proxies, and the shape of the policy functions is identified from the pricing functions. The model leads to closed-form price-dividend ratios under polynomial approximations of the unknown functions and affine state variable dynamics. In the empirical application uncertainty and risk aversion are separately identified from size-sorted stock portfolios exploiting the heterogeneous impact of uncertainty on dividend policy across small and large firms. I find an asymmetric and convex response in consumption (-) and dividend growth (+) towards uncertainty shocks, which together with moderate uncertainty aversion, can generate large leverage effects and divergence between macroeconomic and stock market volatility. Chapter 3 studies the nonparametric identification and estimation of projected pricing kernels implicit in the pricing of options, the underlying asset, and a riskfree bond. The sieve minimum-distance estimator based on conditional moment restrictions avoids the need to compute ratios of estimated risk-neutral and physical densities, and leads to stable estimates even in regions with low probability mass. The conditional empirical likelihood (CEL) variant of the estimator is used to extract implied densities that satisfy the pricing restrictions while incorporating the forwardlooking information from option prices. Moreover, I introduce density combinations in the CEL framework to measure the relative importance of changes in the physical return distribution and in the pricing kernel. The nonlinear dynamic pricing kernels can be used to understand return predictability, and provide model-free quantities that can be compared against those implied by structural asset pricing models.

Cette thèse consiste en une série d'applications du calcul stochastique aux mathématiques financières. Elle est composée de quatre chapitres. Dans le premier on étudie le rapport entre la complétude du marché et l'extrémalité des mesures martingales equivalentes dans le cas d'une infinité d'actifs. Dans le deuxième on trouve des conditions équivalentes à l'existence et unicité d'une mesure martingale equivalente sous la quelle le processus des prix suit des lois n-dimensionnelles données à n fixe. Dans le troisième on étend à un marché admettant une infinité dénombrable d'actifs une charactérisation de la stratégie de couverture optimale (pour le critère moyenne-variance) basé sur une technique de changement de numéraire et extension artificielle. Enfin, dans le quatrième on s'occupe du problème de couverture d'un actif contingent dans un marché avec information asymetrique.

<p>1.3. Research Questions.</p><p>With this in mind, the research questions of this work are:</p><p>1. Is the Capital Asset Pricing Model still applicable despite the heavy impact of the financial crisis on the financial systems?</p><p>2. What happens to this model when the risk free rate approaches zero?</p><p>3. Is there a relationship between the riskiness of an asset and the risk-free interestrate when the latter is approaching the zero level?</p>

Diss. Stockholm : Handelshögskolan, 2006

This dissertation is concerned with the relationship between accounting earnings and stock prices. It consists of three empirical papers, all using a sample of firms listed on the Stockholm Stock Exchange (1990-2008). The first paper documents the existence of a drift in stock prices subsequent to quarterly earnings announcements. Two interesting empirical observations are that the drift is only significant for longer holding periods and that the drift on the short position, i.e. after bad earnings news, is negligible. The lack of downward drift on the short position is interpreted as an indication of the post-earnings announcement drift, at least partly, being explained by investors demanding a compensation for a risk factor that is omitted in the test design. The second paper illustrates under what conditions information risk in the earnings signal might explain a low announcement reaction and a price drift in the post-announcement period. It is hypothesized that two earnings signals – based either on GAAP earnings or core earnings – have different levels of information uncertainty with respect to how they depict the value creation of the firm. In the empirical sections, it is concluded that the low immediate announcement reaction and high post-announcement drift for the GAAP earnings signal is due to this signal being perceived by investors as containing more uncertainty than the core earnings signal. It is argued that this uncertainty might be due to GAAP earnings encompassing items that prior research has shown more likely to be manipulated and/or to contain estimation error. The positive association between information risk and expected return is further investigated in the third paper, where information risk is measured by earnings quality metrics. Using a new approach to estimate the implied cost of capital, it is found that Swedish investors demand a higher expected return for firms with poor earnings quality, i.e. firms associated with higher information risk. / Diss. Stockholm : Handelshögskolan i Stockholm, 2011

This thesis consists of four essays on topics relating to the fields of international portfolio choice, trading behavior, and asset pricing. "Direct Foreign Ownership, Institutional Investors, and Firm Characteristics" analyzes portfolios of Swedish stocks held by foreign investors. The analysis reveals that foreigners tilt their portfolios to firms with certain attributes. It is also shown that the seemingly specific preferences of foreign investors are driven by the fact that they are large institutional investors, and are not linked to their national origin. "Foreigners' Trades in Risky Assets: An assessment of  Investment Behavior and Performance" analyzes foreigners' trading activities. It is shown that foreigners trade more than domestic investors. Further, they trade as non-informed trend followers in that they buy stocks that have recently done well. Nonetheless, after the liberalization of Sweden's stock market, foreigners' purchases have led to a permanent price increase and to a reduction in the cost of equity capital. "Exchange Rate Exposure, Risk Premia, and Firm Characteristics" shows that about fifty percent of Swedish listed firms are affected by exchange rate fluctuations. The sign and magnitude of exchange rate exposure are characterized across industries as well as firm attributes. The empirical analysis suggests that exposure can be eliminated through diversification, and that exchange rate risk is not priced. "Conditioning Information in Tactical Asset Allocation" examines whether investors can exploit the predictability in time-varying expected returns on Swedish stocks and bonds. It is shown that dynamic allocation strategies, based on conditioning information, significantly outperform several benchmark portfolios. This superior performance is not only statistically significant, it is economically large. / Diss. Stockholm : Handelshögsk.

This thesis contain three chapters. Default Risk in Corporate Bond Pricing. This chapter provides a model for how the corporate bond default risk influences the systematic risk and an empirical analysis of the systematic and idiosyncratic parts of U.S. corporate bond returns during 2001-2005. The average corporate bond beta is low and positive (0.06). Investment grade bonds have negative betas (between - 0.01 and -0.13) and non-investment grade bonds have positive betas (between 0.11 and 1.48), but both groups have similar within groups systematic risks. When controls for interest rate and liquidity risks are introduced there are still remaining default probabilities, implying that the default risk is in part systematic and in part idiosyncratic.   Returns to Defaulted Corporate Bonds.   In the second chapter short term excess returns in a sample of 279 defaulted US corporate bonds are tested for using multiple regression analysis. There are robust excess returns after controlling for market and liquidity risk. The expected recovery rate during 2001-2006 is estimated to be, on average, four percentage points lower the first month after default than the present value of the recovery rate after nine months. Capital Structure Choices.   The trade-off and pecking order theories are tested using both established tests from the literature and new tests. The main contributions of this chapter are the new tests of financing of operating net assets (for the pecking order theory), the mean reversion tests (for the trade-off theory) and the test of mean reversion and trends. These tests allow for extended conclusions on the validity of the pecking order versus the tradeoff theory. / <p>Diss. Stockholm : Handelshögskolan, 2008 Sammanfattning jämte 3 uppsatser</p>

1.3. Research Questions. With this in mind, the research questions of this work are: 1. Is the Capital Asset Pricing Model still applicable despite the heavy impact of the financial crisis on the financial systems? 2. What happens to this model when the risk free rate approaches zero? 3. Is there a relationship between the riskiness of an asset and the risk-free interestrate when the latter is approaching the zero level?

In the first essay, I decompose inflation risk into (i) a part that is correlated with real returns on the market portfolio and factors that determine investor’s preferences and investment opportunities and (ii) a residual part. I show that only the first part earns a risk premium. All nominal Treasury bonds, including the nominal money-market account, are equally exposed to the residual part except inflation-protected Treasury bonds, which provide a means to hedge it. Every investor should put 100% of his wealth in the market portfolio and inflation-protected Treasury bonds and hold a zero-investment portfolio of nominal Treasury bonds and the nominal money market account. In the second essay, I solve the dynamic asset allocation problem of finite lived, constant relative risk averse investors who face inflation risk and can invest in cash, nominal bonds, equity, and inflation-protected bonds when the investment opportunityset is determined by the expected inflation rate. I estimate the model with nominal bond, inflation, and stock market data and show that if expected inflation increases, then investors should substitute inflation-protected bonds for stocks and they should borrow cash to buy long-term nominal bonds. In the lastessay, I discuss how heterogeneity in preferences among investors withexternal non-addictive habit forming preferences affects the equilibrium nominal term structure of interest rates in a pure continuous time exchange economy and complete securities markets. Aggregate real consumption growth and inflation are exogenously specified and contain stochastic components thataffect their means andvolatilities. There are two classes of investors who have external habit forming preferences and different localcurvatures oftheir utility functions. The effects of time varying risk aversion and different inflation regimes on the nominal short rate and the nominal market price of risk are explored, and simple formulas for nominal bonds, real bonds, and inflation risk premia that can be numerically evaluated using Monte Carlo simulation techniques are provided.