Spelling suggestions: "subject:"brazil:risk"" "subject:"build:risk""
11 |
Essays on Mutual Funds and Fund ManagersLi, Ma 28 August 2018 (has links)
Die vorliegende Dissertation besteht aus drei Kapiteln über die Investmentfonds. Das erste Kapitel befasst sich mit der Rolle der Fondsmanager in der Bilanzverschönerung. Auf Basis der Analyse der Karrierewege von amerikanischen Fondsmanagern werden signifikante zusammenwirkende Manager-Fixed-Effects identifiziert, die nach der Kontrolle der endogenen Matching-Probleme immer noch robust sind. Die geschätzten Manager-Fixed-Effects haben signifikante Einflüsse auf die Out-of-Sample-Vorhersagen. Außerdem wird festgestellt, dass die Verriegelungen der Investmentfonds, die von gemeinsamen Managern verwaltet wurden, wichtige Kanäle für die Bilanzverschönerung verursachen. Das zweite Kapitel beschäftigt sich mit den Investmentstrategien der Fonds im Hinblick auf die Nutzung von Credit Default Swaps (CDS). Die Zuordnung der CDS-Positionen der Investmentfonds zu ihrem Bestandportfolio bietet eine neue Methodik zur Identifizierung der CDS-Strategien und kompensiert somit die Analysen der existierenden Literatur auf der Makroebene. Die Ergebnisse zeigen, dass die Anreize zur Risikoreduzierung die Spekulationsanreize dominieren, insbesondere, wenn die Kreditexposition durch ungedeckte Leerverkäufe der CDS-Verträge erhöht wird. Die erfahrenen Fondsmanager tendieren dazu, mehr Kreditrisiko in Kauf zu nehmen, während es für die Fondsmanagerinnen wahrscheinlicher als für ihre männlichen Kollegen ist, gegen das bestehende Risiko abzusichern. Der letzte Teil nimmt die Pleite von Lehman Brothers unter die Lupe, um sich mit der daraus resultierenden unerwarteten Schließung der CDS-Positionen als einem natürlichen Experiment auseinanderzusetzten. Diese Studie dient zur Untersuchung der Risiko- und Leistungsimplikationen der CDS-Investments der Fonds. Die Investmentfonds besitzen bei ihren CDS-Transaktionen im Durchschnitt einen beachtlichen Teil Extremrisiko. Während die CDS-Nutzer von guten Gesamtmarktlagen profitieren, erleiden sie unter Verlusten bei geclusterten Ausfällen. / This dissertation comprises of three chapters on mutual funds. The first chapter establishes the role of managers in the deceptive practice of window dressing. Employing comprehensive career history of U.S. mutual fund managers, I find strong jointly significant manager fixed effects, which are robust after addressing endogenous matching concerns. The estimated manager fixed effects are significant in making out-of-sample predictions. Further I establish that mutual fund interlocks through common managers are important channels that spread window dressing. The second chapter studies the investment strategies of mutual funds regarding their use of credit default swaps (CDS). Matches between mutual funds’ CDS positions and their underlying portfolio in the holdings facilitate a new approach in identifying CDS strategies that complements the “macro” level analyses in the existing literature. I find risk reducing incentives are dominated by speculative incentives, especially those to increase credit exposure via naked short CDS contracts. Experienced fund managers tend to take on more credit risk, while female managers are more likely to hedge comparing with their male peers. The third chapter employs the collapse of Lehman Brothers and the resulting sudden closures of CDS positions as a natural experiment to examine the risk and performance implications of mutual funds’ CDS investments. Funds on average load up on a significant amount of tail risk by trading CDS. While CDS users benefit when market conditions are favorable, they suffer during periods of clustered defaults.
|
12 |
Essays on asset allocation strategies for defined contribution plansBasu, Anup K. January 2008 (has links)
Asset allocation is the most influential factor driving investment performance. While researchers have made substantial progress in the field of asset allocation since the introduction of mean-variance framework by Markowitz, there is little agreement about appropriate portfolio choice for multi-period long horizon investors. Nowhere this is more evident than trustees of retirement plans choosing different asset allocation strategies as default investment options for their members. This doctoral dissertation consists of four essays each of which explores either a novel or an unresolved issue in the area of asset allocation for individual retirement plan participants. The goal of the thesis is to provide greater insight into the subject of portfolio choice in retirement plans and advance scholarship in this field. The first study evaluates different constant mix or fixed weight asset allocation strategies and comments on their relative appeal as default investment options. In contrast to past research which deals mostly with theoretical or hypothetical models of asset allocation, we investigate asset allocation strategies that are actually used as default investment options by superannuation funds in Australia. We find that strategies with moderate allocation to stocks are consistently outperformed in terms of upside potential of exceeding the participant’s wealth accumulation target as well as downside risk of falling below that target by very aggressive strategies whose allocation to stocks approach 100%. The risk of extremely adverse wealth outcomes for plan participants does not appear to be very sensitive to asset allocation. Drawing on the evidence of the previous study, the second essay explores possible solutions to the well known problem of gender inequality in retirement investment outcomes. Using non-parametric stochastic simulation, we simulate iv and compare the retirement wealth outcomes for a hypothetical female and male worker under different assumptions about breaks in employment, superannuation contribution rates, and asset allocation strategies. We argue that modest changes in contribution and asset allocation strategy for the female plan participant are necessary to ensure an equitable wealth outcome in retirement. The findings provide strong evidence against gender-neutral default contribution and asset allocation policy currently institutionalized in Australia and other countries. In the third study we examine the efficacy of lifecycle asset allocation models which allocate aggressively to risky asset classes when the employee participants are young and gradually switch to more conservative asset classes as they approach retirement. We show that the conventional lifecycle strategies make a costly mistake by ignoring the change in portfolio size over time as a critical input in the asset allocation decision. Due to this portfolio size effect, which has hitherto remained unexplored in literature, the terminal value of accumulation in retirement account is critically dependent on the asset allocation strategy adopted by the participant in later years relative to early years. The final essay extends the findings of the previous chapter by proposing an alternative approach to lifecycle asset allocation which incorporates performance feedback. We demonstrate that strategies that dynamically alter allocation between growth and conservative asset classes at different points on the investment horizon based on cumulative portfolio performance relative to a set target generally result in superior wealth outcomes compared to those of conventional lifecycle strategies. The dynamic allocation strategy exhibits clear second-degree stochastic dominance over conventional strategies which switch assets in a deterministic manner as well as balanced diversified strategies.
|
13 |
Tail risk in the hedge fund industrySantos, Eduardo Alonso Marza dos 28 May 2015 (has links)
Submitted by Eduardo Alonso Marza dos Santos (eduardo.marza.santos@gmail.com) on 2015-06-21T10:30:55Z
No. of bitstreams: 1
Eduardo_A_M_Santos.pdf: 646820 bytes, checksum: aaba122a576d7c75ad0e5803539c25d4 (MD5) / Approved for entry into archive by Suzinei Teles Garcia Garcia (suzinei.garcia@fgv.br) on 2015-06-22T11:46:18Z (GMT) No. of bitstreams: 1
Eduardo_A_M_Santos.pdf: 646820 bytes, checksum: aaba122a576d7c75ad0e5803539c25d4 (MD5) / Made available in DSpace on 2015-06-22T11:56:18Z (GMT). No. of bitstreams: 1
Eduardo_A_M_Santos.pdf: 646820 bytes, checksum: aaba122a576d7c75ad0e5803539c25d4 (MD5)
Previous issue date: 2015-05-28 / The dissertation goal is to quantify the tail risk premium embedded into hedge funds' returns. Tail risk is the probability of extreme large losses. Although it is a rare event, asset pricing theory suggests that investors demand compensation for holding assets sensitive to extreme market downturns. By de nition, such events have a small likelihood to be represented in the sample, what poses a challenge to estimate the e ects of tail risk by means of traditional approaches such as VaR. The results show that it is not su cient to account for the tail risk stemming from equities markets. Active portfolio management employed by hedge funds demand a speci c measure to estimate and control tail risk. Our proposed factor lls that void inasmuch it presents explanatory power both over the time series as well as the cross-section of funds' returns. / O objetivo do trabalho é quanti car o prêmio de risco de cauda presente nos retornos de fundos de investimento americanos. Risco de cauda é o risco de perdas excepcionalmente elevadas. Apesar de ser um evento raro, a teoria de apreçamento de ativos sugere que os investidores exigem um prêmio de risco para reter ativos expostos a eventos negativos extremos (eventos de cauda). Por de nição, observações extremas têm baixa probabilidade de estarem presentes na amostra, o que di culta a estimação dos impactos de risco de cauda sobre os retornos e reduz o poder de técnicas tradicionais como VaR. Os resultados indicam que não é su ciente controlar somente para o risco de cauda do mercado de capitais. A gestão ativa de portfólio por parte dos gestores de fundos requer uma medida própria para estimação e o controle de risco de cauda. O fator de risco de cauda que propomos cumpre este papel ao apresentar poder explicativo tanto na série temporal dos retornos quanto no corte transversal.
|
14 |
The Impact of Mergers & Acquisitions on Credit- and Investment risk. : -Evidence from SwedenDahlberg, Casper, Lundberg, Max January 2022 (has links)
We examine the impact of Mergers & Acquisitions on credit- and investment risk using a sample of 402 acquisitions by 215 Swedish firms from 2000 to 2020. We find significant evidence that, on average, M&A increases the credit risk and inversely decreases the investment risk of the acquiring firm. Our results indicate that firm credit risk however is positively correlated with investment risk. After controlling for specific deal- and firm characteristics, our findings suggest that managerial hubris decreases the level of credit risk and increases the level of investment risk in acquiring firms. Our results are consistent with the asymmetric information hypothesis that managers may exploit the volatility of their stock price to hide risk-increasing activities. We also observe that acquirers with high pre-deal credit risk undertake acquisitions that decrease credit risk and increase investment risk. We find no significant impact from neither method of payment nor valuation errors.
|
15 |
Portfolio selection and hedge funds : linearity, heteroscedasticity, autocorrelation and tail-riskBianchi, Robert John January 2007 (has links)
Portfolio selection has a long tradition in financial economics and plays an integral role in investment management. Portfolio selection provides the framework to determine optimal portfolio choice from a universe of available investments. However, the asset weightings from portfolio selection are optimal only if the empirical characteristics of asset returns do not violate the portfolio selection model assumptions. This thesis explores the empirical characteristics of traditional assets and hedge fund returns and examines their effects on the assumptions of linearity-in-the-mean testing and portfolio selection. The encompassing theme of this thesis is the empirical interplay between traditional assets and hedge fund returns. Despite the paucity of hedge fund research, pension funds continue to increase their portfolio allocations to global hedge funds in an effort to pursue higher risk-adjusted returns. This thesis presents three empirical studies which provide positive insights into the relationships between traditional assets and hedge fund returns. The first two empirical studies examine an emerging body of literature which suggests that the relationship between traditional assets and hedge fund returns is non-linear. For mean-variance investors, non-linear asset returns are problematic as they do not satisfy the assumption of linearity required for the covariance matrix in portfolio selection. To examine the linearity assumption as it relates to a mean-variance investor, a hypothesis test approach is employed which investigates the linearity-in-the-mean of traditional assets and hedge funds. The findings from the first two empirical studies reveal that conventional linearity-in-the-mean tests incorrectly conclude that asset returns are nonlinear. We demonstrate that the empirical characteristics of heteroscedasticity and autocorrelation in asset returns are the primary sources of test mis-specification in these linearity-in-the-mean hypothesis tests. To address this problem, an innovative approach is proposed to control heteroscedasticity and autocorrelation in the underlying tests and it is shown that traditional assets and hedge funds are indeed linear-in-the-mean. The third and final study of this thesis explores traditional assets and hedge funds in a portfolio selection framework. Following the theme of the previous two studies, the effects of heteroscedasticity and autocorrelation are examined in the portfolio selection context. The characteristics of serial correlation in bond and hedge fund returns are shown to cause a downward bias in the second sample moment. This thesis proposes two methods to control for this effect and it is shown that autocorrelation induces an overallocation to bonds and hedge funds. Whilst heteroscedasticity cannot be directly examined in portfolio selection, empirical evidence suggests that heteroscedastic events (such as those that occurred in August 1998) translate into the empirical feature known as tail-risk. The effects of tail-risk are examined by comparing the portfolio decisions of mean-variance analysis (MVA) versus mean-conditional value at risk (M-CVaR) investors. The findings reveal that the volatility of returns in a MVA portfolio decreases when hedge funds are included in the investment opportunity set. However, the reduction in the volatility of portfolio returns comes at a cost of undesirable third and fourth moments. Furthermore, it is shown that investors with M-CVaR preferences exhibit a decreasing demand for hedge funds as their aversion for tail-risk increases. The results of the thesis highlight the sensitivities of linearity tests and portfolio selection to the empirical features of heteroscedasticity, autocorrelation and tail-risk. This thesis contributes to the literature by providing refinements to these frameworks which allow improved inferences to be made when hedge funds are examined in linearity and portfolio selection settings.
|
16 |
Essays on tail risk in macroeconomics and finance: measurement and forecastingRicci, Lorenzo 13 February 2017 (has links)
This thesis is composed of three chapters that propose some novel approaches on tail risk for financial market and forecasting in finance and macroeconomics. The first part of this dissertation focuses on financial market correlations and introduces a simple measure of tail correlation, TailCoR, while the second contribution addresses the issue of identification of non- normal structural shocks in Vector Autoregression which is common on finance. The third part belongs to the vast literature on predictions of economic growth; the problem is tackled using a Bayesian Dynamic Factor model to predict Norwegian GDP.Chapter I: TailCoRThe first chapter introduces a simple measure of tail correlation, TailCoR, which disentangles linear and non linear correlation. The aim is to capture all features of financial market co- movement when extreme events (i.e. financial crises) occur. Indeed, tail correlations may arise because asset prices are either linearly correlated (i.e. the Pearson correlations are different from zero) or non-linearly correlated, meaning that asset prices are dependent at the tail of the distribution.Since it is based on quantiles, TailCoR has three main advantages: i) it is not based on asymptotic arguments, ii) it is very general as it applies with no specific distributional assumption, and iii) it is simple to use. We show that TailCoR also disentangles easily between linear and non-linear correlations. The measure has been successfully tested on simulated data. Several extensions, useful for practitioners, are presented like downside and upside tail correlations.In our empirical analysis, we apply this measure to eight major US banks for the period 2003-2012. For comparison purposes, we compute the upper and lower exceedance correlations and the parametric and non-parametric tail dependence coefficients. On the overall sample, results show that both the linear and non-linear contributions are relevant. The results suggest that co-movement increases during the financial crisis because of both the linear and non- linear correlations. Furthermore, the increase of TailCoR at the end of 2012 is mostly driven by the non-linearity, reflecting the risks of tail events and their spillovers associated with the European sovereign debt crisis. Chapter II: On the identification of non-normal shocks in structural VARThe second chapter deals with the structural interpretation of the VAR using the statistical properties of the innovation terms. In general, financial markets are characterized by non- normal shocks. Under non-Gaussianity, we introduce a methodology based on the reduction of tail dependency to identify the non-normal structural shocks.Borrowing from statistics, the methodology can be summarized in two main steps: i) decor- relate the estimated residuals and ii) the uncorrelated residuals are rotated in order to get a vector of independent shocks using a tail dependency matrix. We do not label the shocks a priori, but post-estimate on the basis of economic judgement.Furthermore, we show how our approach allows to identify all the shocks using a Monte Carlo study. In some cases, the method can turn out to be more significant when the amount of tail events are relevant. Therefore, the frequency of the series and the degree of non-normality are relevant to achieve accurate identification.Finally, we apply our method to two different VAR, all estimated on US data: i) a monthly trivariate model which studies the effects of oil market shocks, and finally ii) a VAR that focuses on the interaction between monetary policy and the stock market. In the first case, we validate the results obtained in the economic literature. In the second case, we cannot confirm the validity of an identification scheme based on combination of short and long run restrictions which is used in part of the empirical literature.Chapter III :Nowcasting NorwayThe third chapter consists in predictions of Norwegian Mainland GDP. Policy institutions have to decide to set their policies without knowledge of the current economic conditions. We estimate a Bayesian dynamic factor model (BDFM) on a panel of macroeconomic variables (all followed by market operators) from 1990 until 2011.First, the BDFM is an extension to the Bayesian framework of the dynamic factor model (DFM). The difference is that, compared with a DFM, there is more dynamics in the BDFM introduced in order to accommodate the dynamic heterogeneity of different variables. How- ever, in order to introduce more dynamics, the BDFM requires to estimate a large number of parameters, which can easily lead to volatile predictions due to estimation uncertainty. This is why the model is estimated with Bayesian methods, which, by shrinking the factor model toward a simple naive prior model, are able to limit estimation uncertainty.The second aspect is the use of a small dataset. A common feature of the literature on DFM is the use of large datasets. However, there is a literature that has shown how, for the purpose of forecasting, DFMs can be estimated on a small number of appropriately selected variables.Finally, through a pseudo real-time exercise, we show that the BDFM performs well both in terms of point forecast, and in terms of density forecasts. Results indicate that our model outperforms standard univariate benchmark models, that it performs as well as the Bloomberg Survey, and that it outperforms the predictions published by the Norges Bank in its monetary policy report. / Doctorat en Sciences économiques et de gestion / info:eu-repo/semantics/nonPublished
|
17 |
Modélisation de la Volatilité Implicite, Primes de Risque d’Assurance, et Stratégies d’Arbitrage de Volatilité / Implied Volatility Modelling, Tail Risk Premia, and Volatility Arbitrage StrategiesAl Wakil, Anmar 11 December 2017 (has links)
Les stratégies de volatilité ont connu un rapide essor suite à la crise financière de 2008. Or, les récentes performances catastrophiques de ces instruments indiciels ont remis en question leurs contributions en couverture de portefeuille. Mes travaux de thèse visent à repenser, réinventer la philosophie des stratégies de volatilité. Au travers d'une analyse empirique préliminaire reposant sur la théorie de l'utilité espérée, le chapitre 1 dresse le diagnostic des stratégies traditionnelles de volatilité basées sur la couverture de long-terme par la réplication passive de la volatilité implicite. Il montre que, bien que ce type de couverture bat la couverture traditionnelle, elle s'avère inappropriée pour des investisseurs peu averses au risque.Le chapitre 2 ouvre la voie à une nouvelle génération de stratégies de volatilité, actives, optionnelles et basées sur l'investissement factoriel. En effet, notre décomposition analytique et empirique du smile de volatilité implicite en primes de risque implicites, distinctes et investissables permet de monétiser de manière active le portage de risques d'ordres supérieurs. Ces primes de risques mesurent l'écart de valorisation entre les distributions neutres au risque et les distributions physiques.Enfin, le chapitre 3 compare notre approche investissement factoriel avec les stratégies de volatilité employées par les hedge funds. Notre essai montre que nos stratégies de primes de risque d'assurance sont des déterminants importants dans la performance des hedge funds, tant en analyse temporelle que cross-sectionnelle. Ainsi, nous mettons en évidence dans quelle mesure l'alpha provient en réalité de la vente de stratégies d'assurance contre le risque extrême. / Volatility strategies have flourished since the Great Financial Crisis in 2008. Nevertheless, the recent catastrophic performance of such exchange-traded products has put into question their contributions for portfolio hedging and diversification. My thesis work aims to rethink and reinvent the philosophy of volatility strategies.From a preliminary empirical study based on the expected utility theory, Chapter 1 makes a diagnostic of traditional volatility strategies, based on buy-and-hold investments and passive replication of implied volatility. It exhibits that, although such portfolio hedging significantly outperforms traditional hedging, it appears strongly inappropriate for risk-loving investors.Chapter 2 paves the way for a new generation of volatility strategies, active, option-based and factor-based investing. Indeed, our both analytical and empirical decomposition of implied volatility smiles into a combination of implied risk premia, distinct and tradeable, enables to harvest actively the compensation for bearing higher-order risks. These insurance risk premia measure the pricing discrepanciesbetween the risk-neutral and the physical probability distributions.Finally, Chapter 3 compares our factor-based investing approach to the strategies usually employed in the hedge fund universe. Our essay clearly evidences that our tail risk premia strategies are incremental determinants in the hedge fund performance, in both the time-series and the cross-section of returns. Hence, we exhibit to what extent hedge fund alpha actually arises from selling crash insurance strategies against tail risks.
|
18 |
Tail Risk Protection via reproducible data-adaptive strategiesSpilak, Bruno 15 February 2024 (has links)
Die Dissertation untersucht das Potenzial von Machine-Learning-Methoden zur Verwaltung von Schwanzrisiken in nicht-stationären und hochdimensionalen Umgebungen. Dazu vergleichen wir auf robuste Weise datenabhängige Ansätze aus parametrischer oder nicht-parametrischer Statistik mit datenadaptiven Methoden. Da datengetriebene Methoden reproduzierbar sein müssen, um Vertrauen und Transparenz zu gewährleisten, schlagen wir zunächst eine neue Plattform namens Quantinar vor, die einen neuen Standard für wissenschaftliche Veröffentlichungen setzen soll. Im zweiten Kapitel werden parametrische, lokale parametrische und nicht-parametrische Methoden verglichen, um eine dynamische Handelsstrategie für den Schutz vor Schwanzrisiken in Bitcoin zu entwickeln. Das dritte Kapitel präsentiert die Portfolio-Allokationsmethode NMFRB, die durch eine Dimensionsreduktionstechnik hohe Dimensionen bewältigt. Im Vergleich zu klassischen Machine-Learning-Methoden zeigt NMFRB in zwei Universen überlegene risikobereinigte Renditen. Das letzte Kapitel kombiniert bisherige Ansätze zu einer Schwanzrisikoschutzstrategie für Portfolios. Die erweiterte NMFRB berücksichtigt Schwanzrisikomaße, behandelt nicht-lineare Beziehungen zwischen Vermögenswerten während Schwanzereignissen und entwickelt eine dynamische Schwanzrisikoschutzstrategie unter Berücksichtigung der Nicht-Stationarität der Vermögensrenditen. Die vorgestellte Strategie reduziert erfolgreich große Drawdowns und übertrifft andere moderne Schwanzrisikoschutzstrategien wie die Value-at-Risk-Spread-Strategie. Die Ergebnisse werden durch verschiedene Data-Snooping-Tests überprüft. / This dissertation shows the potential of machine learning methods for managing tail risk in a non-stationary and high-dimensional setting. For this, we compare in a robust manner data-dependent approaches from parametric or non-parametric statistics with data-adaptive methods. As these methods need to be reproducible to ensure trust and transparency, we start by proposing a new platform called Quantinar, which aims to set a new standard for academic publications. In the second chapter, we dive into the core subject of this thesis which compares various parametric, local parametric, and non-parametric methods to create a dynamic trading strategy that protects against tail risk in Bitcoin cryptocurrency. In the third chapter, we propose a new portfolio allocation method, called NMFRB, that deals with high dimensions thanks to a dimension reduction technique, convex Non-negative Matrix Factorization. This technique allows us to find latent interpretable portfolios that are diversified out-of-sample. We show in two universes that the proposed method outperforms other classical machine learning-based methods such as Hierarchical Risk Parity (HRP) concerning risk-adjusted returns. We also test the robustness of our results via Monte Carlo simulation. Finally, the last chapter combines our previous approaches to develop a tail-risk protection strategy for portfolios: we extend the NMFRB to tail-risk measures, we address the non-linear relationships between assets during tail events by developing a specific non-linear latent factor model, finally, we develop a dynamic tail risk protection strategy that deals with the non-stationarity of asset returns using classical econometrics models. We show that our strategy is successful at reducing large drawdowns and outperforms other modern tail-risk protection strategies such as the Value-at-Risk-spread strategy. We verify our findings by performing various data snooping tests.
|
Page generated in 0.0407 seconds