Submitted by Caio Machado (caiohm@gmail.com) on 2017-05-18T18:01:09Z No. of bitstreams: 1 Tese_Machado2017.pdf: 1442885 bytes, checksum: 6de78cd6ea7228909465f19bc20ae0ce (MD5) / Approved for entry into archive by Suzinei Teles Garcia Garcia (suzinei.garcia@fgv.br) on 2017-05-18T19:16:58Z (GMT) No. of bitstreams: 1 Tese_Machado2017.pdf: 1442885 bytes, checksum: 6de78cd6ea7228909465f19bc20ae0ce (MD5) / Made available in DSpace on 2017-05-18T20:24:11Z (GMT). No. of bitstreams: 1 Tese_Machado2017.pdf: 1442885 bytes, checksum: 6de78cd6ea7228909465f19bc20ae0ce (MD5) Previous issue date: 2017-05-11 / Coordination failures are often said to play an important role in business cycles. If agents’ incentives of taking a given action depend on the amount of other agents expected to take the same action, coordination failures can often arise. Firms may not invest because they do not expect others to invest, confirming their initial expectations. Similarly, banks may not lend because they do not expect others to lend. This dissertation analyzes different environments in which crises arise as a result of coordination failures. The first chapter analyzes an economy that is subject to a dynamic coordination problem. Because of aggregate demand externalities, firms’ incentives to increase their production depend on expected demand, which in turn depends on the amount produced by other firms. The problem is dynamic since firms do not take investment decisions at the same time, implying that a firm deciding today is trying to forecast what other firms will decide in the future. This opens the possibility of dynamic coordination traps: firms do not invest today because they do not believe others will invest tomorrow, generating lower incentives for firms to invest at future dates. This chapter focuses on the following questions: In economies subject to dynamic coordination traps, what is the optimal stimulus policies? Should policy makers provide higher incentives to production in times of low economic activity? The answer is that a constant subsidy implements the first-best in an economy where beliefs are endogenously determined. The reason is that, although it is harder to coordinate in times of low economic activity, agents are naturally more optimistic about the future in times of poor economic activity and reasonably good fundamentals. This optimism arise from the fact that in bad times negative shocks do not change the level of economic activity, while positive shocks may end a recession. The second chapter proposes a model to study unusually deep financial crises. Previous empirical work has found that financial crises are very deep and persistent on average, but there is a lot of heterogeneity across different episodes. Some financial crises feature a very distressed financial sector, but little distress on the real sector, while others are real macroeconomic disasters. In light of this evidence, I propose a model in which there is a highly non-linear feedback between the real and the financial sector. Disaster episodes arise from the dynamic interaction of two frictions: coordination frictions and financial frictions. When banks have weak balance sheets they do not intermediate much capital. This causes firms to get trapped in a self-reinforcing regime with low aggregate demand, which ends up provoking further damage to banks’ balance sheets. I use the model as a laboratory to study unusually deep financial crises and the effects of some policies. It is shown that the effects of disasters go far beyond what we observe during those episodes: they imply very low asset prices, economic growth and welfare, even in good times and when their probability is very small. Policies that protect the financial sector from those episodes can be very beneficial. Moreover, higher risk-taking in bad times may improve economic growth, welfare and financial stability. The third chapter studies the policy trade-off of a regulator that wants to avoid coordination failures, but at the same time does not want to generate distortions arising from moral hazard. Banks have investment opportunities with an expected return that depends positively on the amount of other banks undertaking similar investments, opening room for coordination failures. At the same time, banks may risk-shift to projects with smaller expected return but higher volatility. By providing guarantees in case of failures, a regulator can enhance coordination, but that leads banks to switch to worse projects. It is shown that in some states a regulator will provide no guarantees, even if it that means allowing a coordination failure to happen. Moreover, the possibility of risk-shifting reduces the amount of guarantees needed to avoid a coordination failure. / Com frequência argumenta-se que falhas de coordenação têm um papel importante no ciclo de negócios. Se os incentivos dos agentes a realizar determinada ação depende da quantidade esperada de outros agentes que tomarão a mesma ação, falhas de coordenação podem acontecer. Empresas podem não investir porque não esperam que outras empresas irão investir, confirmando suas expectativas iniciais. De maneira similar, bancos podem não conceder empréstimos porque eles não esperam que outros bancos irão fazer o mesmo. Esta tese analisa diferentes ambientes onde crises surgem como o resultado de falhas de coordenação. O primeiro capítulo analisa uma economia que está sujeita a falhas de coordenação dinâmicas. Por causa de externalidades de demanda agregada, os incentivos para uma dada firma aumentar sua produção dependem da demanda esperada, que por sua vez depende da quantidade produzida por outras firmas. O problema é dinâmico porque as firmas não tomam decisões de investimento ao mesmo tempo, implicando que uma firma tomando decisões hoje está tentando prever o que outras firmas decidirão no futuro. Isso abre a possibilidade de falhas de coordenação dinâmicas: firmas não investem hoje porque elas não acreditam que outras firmas investirão amanhã, gerando incentivos menores para outras firmas investirem no futuro. Este capítulo foca nas seguintes questões: Em economias sujeitas a este problema de coordenação dinâmico, qual a política de estímulo ótima? O governo deveria prover mais estímulos em épocas de baixa atividade econômica? A resposta é que um subsídio constante implementa o ótimo nesta economia. O motivo é que, embora seja mais difícil coordenar em tempos de baixa atividade, os agentes estão naturalmente mais otimistas sobre o futuro em tempos de baixa atividade e fundamentos razoavelmente bons. Este otimismo surge do fato que em tempos ruins choques negativos não alteram o nível de atividade econômica, mas choques positivos podem acabar com uma recessão. O segundo capítulo desta tese propõe um modelo para estudar crises financeiras mais severas que o usual. Trabalhos empíricos prévios mostram que, em geral, crises financeiras são muito profundas e persistentes, mas também que há muita heterogeneidade entre diferentes episódios. Algumas crises financeiras causam enormes danos no sistema financeiro, mas pouco dano no setor real, enquanto outras são verdadeiros desastres macroeconômicos. À luz desta evidência, esta tese propõe um modelo onde há um feedback extremamente não linear entre o setor financeiro e o setor real. Desastres surgem através da interação dinâmica de duas fricções: fricções de coordenação e fricções financeiras. Quando os bancos estão com problemas em seus balanços, eles optam por intermediar menos capital. Isso leva as firmas a entrar em um regime com baixa demanda agregada, que causa ainda mais dano ao capital dos bancos. Este modelo é utilizado como um laboratório para estudar crises financeiras muito severas e o efeito de algumas políticas. É mostrado que os efeitos de desastres econômicos vão muito além do que observamos durante estes episódios. Eles levam à queda dos preços de ativos, baixo crescimento e perdas de bem-estar, mesmo que a probabilidade destes eventos seja muito pequena. Finalmente, quando os bancos tomam mais risco em tempos ruins, podemos ter um aumento de crescimento, bem-estar e estabilidade financeira. O terceiro capítulo estuda o trade-off enfrentado por um regulador que quer evitar falhas de coordenação, mas ao mesmo tempo não quer gerar distorções que surgem por conta de risco moral. Os bancos possuem oportunidades de investimento cujo retorno esperado depende positivamente da quantidade de outros bancos investindo em projetos similares, abrindo espaço para a possibilidade de falhas de coordenação. Ao mesmo tempo, bancos podem escolher investir em projetos com menor retorno esperado e maior volatilidade. Ao prover garantias em caso de falha de um banco, um regulador pode melhorar a habilidade que estes têm de coordenar, mas ao mesmo isto pode levar os bancos a tomarem risco excessivo. É mostrado que em alguns estados o regulador não proverá garantias, mesmo que isso implique permitir que uma falha de coordenação aconteça. Ainda, a possibilidade dos bancos tomarem risco excessivo reduz a quantidade de garantias necessárias para evitar uma falha de coordenação.

The main objective of this thesis is to analyze selected sectors of the European capital market by means of methods of technical and fundamental analysis. Based on the results obtained for each frame exchanges, industry sectors and the best investment strategy. The first part deals with the theoretical description of securities to capital markets, investment strategies, methods of assessment of the securities in the capital markets, the theory of efficient markets, market testing and evidence of their effectiveness. On the European stock market index, including the German DAX30 randomly selected ninety nine companies with data for the period 2006 {-} the 2011th The work on the basis of a confirmed capital market inefficiencies can be found active investment strategy to achieve above average returns.

The aim of this diploma work was to analyze a selected segment of the stock exchange market using the theory of market efficiency and the methods of technical and fundamental analysis, to form an optimal investment strategy on the basis of the findings. The American stock exchange market was analyzed. Six different segments of the capital market were selected ? gold, oil and gas pipelines, steel and iron, car parts, food and telecommunication services. Each segment was represented by eight companies. The general characteristics of the companies were compared according to their profits, degree of risk, alpha and beta coefficients. Fundamental analysis was used to monitor the correlation between future profits for 2012 and alpha coefficients for the period 2007 ? 2011. The theory was proven ? at low levels of future profits, high levels of alpha coefficients were measured and vice versa - at high levels of future profits, low levels of alpha coefficients were measured. During efficiency tests, runs tests and correlation tests were monitored. During runs tests, the number of turns of a real file was compared with the number of runs of a simulated file; no distinctive variances were identified in the monitored stock titles. Forms of market efficiency were proven during the correlation tests and runs tests. The methods of technical analysis used were sliding averages, RSI indicators and Momentum. Trading on the basis of technical analysis is not completely possible because we did not succeed in finding an existing optimal strategy. If an optimal strategy works out it is regardless of the segment?s characteristics. I recommend a passive strategy with regards to the fundamental analysis.

We present three chapters on theoretical issues of banking. These deal with bank runs, risk sharing, lending and profitability. In the first chapter, we examine the agency problem in the bank-depositor relationship. Depositors are the principals and banks are the agents. Banks choose investment portfolios and are subject to moral hazard in that they have incentive to take on more risk than desirable to depositors because they are residual claimants. We study an incentive-compatible mechanism that prompts banks to follow a safe investment policy. This mechanism leaves the bank a profit margin in a similar manner to a CEO being paid a bonus by a company. In the second chapter, we extend Allen and Gale (1998) by adding a long-term riskless investment opportunity to the original portfolio of a short-term liquid asset and a long-term risky illiquid asset. Through portfolio diversification, we identify the risk-sharing deposit contract in a three-period model that maximizes the ex-ante expected utility of depositors. Unlike Allen and Gale, there are no information-based bank runs in equilibrium. In addition, our model can improve consumers' welfare over the Allen and Gale model. I also show that the bank will choose to liquidate the cheaper investments, in terms of the gain-loss ratios for the two types of existing long-term assets, when there is liquidity shortage in some cases. Such a policy reduces the liquidation cost and enables the bank to meet the outstanding liability to depositors without large liquidation losses. In the third chapter, we study the role of banks in providing loans to borrower firms. This paper extends the theory of designing optimal loan contracts (for profits) in the Bolton and Scharfstein (1996) model to a setting where asymmetry of information exists. Based on the verifiability of information structure, we analyze complete and incomplete contracts. Through this analysis, optimal, incentive-compatible loan contracts that maximize the expected profit of the bank are characterized. Our analysis suggests that a bank could be induced to liquidate a borrower's project under specific conditions. Furthermore, we identify implementable mechanisms for the renegotiation game given the bargaining power between a borrower and a bank.

No description available.

This study tests for the market efficiency of the Nairobi Securities Exchange (NSE) after the year 2000 to determine the effect of technological advancements on market efficiency. Data that is used is the NSE 20 share index over the period 2001 to 2015; and the NSE All Share Index (NSE ASI) from its initiation during 2008 to 2015. We cannot accept the Efficient Market Hypothesis (EMH) for the NSE using the serial correlation test, the unit root tests and the runs test. However, we can accept the EMH for the more robust variance ratio test. Overall, the results of the market efficiency are mixed. The most significant finding is that the efficiency of the NSE has increased since the year 2000 which suggests that advancements in technology have contributed to the increase in the market efficiency of the NSE. / Business Management / M. Com. (Business Management)

Cette thèse s'intéresse à la modélisation et à l'analyse dessystèmes temps-réel distribués.Un système distribué est constitué de plusieurs composantsqui évoluent de manière partiellement indépendante. Lorsque des actionsexécutables par différentscomposants sont indépendantes, elles sont dites concurrentes.Dans ce cas, elles peuvent être exécutées dans n'importe quel ordre, sanss'influencer, et l'état atteint après ces actions ne dépend pas de leur ordred'exécution.Dans les systèmes temps-réel distribués, les contraintes de temps créent desdépendances complexes entre les composants et les événements qui ont lieu surces composants. Malgré l'omniprésence et l'aspect critique de ces systèmes,beaucoup de leurs propriétés restent encore à étudier.En particulier, la nature distribuée de ces systèmes est souvent laissée de côté.Notre travail s'appuie sur deux formalismesde modélisation: les réseaux de Petri temporels et les réseaux d'automatestemporisés, et est divisé en deux parties.Dans la première partie, nous mettons en évidence les différences entre lessystèmes temporisés centralisés et les systèmes temporisés distribués. Nouscomparons les formalismes principaux et leurs extensions, avec une approcheoriginale qui considère la concurrence.En particulier, nous montrons comment transformer un réseau de Petri temporelen un réseau d'automates temporisés qui a le même comportement distribué.Nous nous intéressons ensuite aux horloges partagées dans lesréseaux d'automates temporisés. Les horloges partagées sont problématiqueslorsque l'on envisage d'implanter ces modèles sur des architecturesdistribuées. Nous montrons comment se passer des horloges partagées, touten préservant le comportement distribué, lorsque cela est possible.Dans la seconde partie, nous nous attachons à formaliser les dépendancesentre les événements dans les représentations en ordre partieldes exécutions des réseaux de Petri (temporels ou non).Les réseaux d'occurrence sont une de ces représentations, et leur structuredonne directement les relations de causalité, conflit et concurrence entreles événements. Cependant, nous montrons que, même dans le cas non temporisé,certaines relations logiques entre les événements nepeuvent pas être directement décrites par ces relations structurelles.Après avoir formalisé les relations logiques en question, nous résolvons leproblème de synthèse suivant: étant donnée une formule logique qui décrit unensemble d'exécutions, construire un réseau d'occurrence associé,quand celui-ci existe.Nous étudions ensuite les relations logiques dans un cadre temporisé simplifié,et montrons que le temps crée des dépendances complexes entre les événements.Ces dépendances peuvent être utilisées pour définir des dépliages canoniques deréseaux de Petri temporels, dans ce cadre simplifié. / This thesis is concerned with the modeling and the analysis of distributedreal-time systems. In distributed systems, components evolve partlyindependently: concurrent actions may be performed in any order, withoutinfluencing each other and the state reached after these actions does notdepends on the order of execution. The time constraints in distributed real-timesystems create complex dependencies between the components and the events thatoccur. So far, distributed real-time systems have not been deeply studied, andin particular the distributed aspect of these systems is often left aside. Thisthesis explores distributed real-time systems. Our work on distributed real-timesystems is based on two formalisms: time Petri nets and networks of timedautomata, and is divided into two parts.In the first part, we highlight the differences between centralized anddistributed timed systems. We compare the main formalisms and their extensions,with a novel approach that focuses on the preservation of concurrency. Inparticular, we show how to translate a time Petri net into a network of timedautomata with the same distributed behavior. We then study a concurrency relatedproblem: shared clocks in networks of timed automata can be problematic when oneconsiders the implementation of a model on a multi-core architecture. We showhow to avoid shared clocks while preserving the distributed behavior, when thisis possible.In the second part, we focus on formalizing the dependencies between events inpartial order representations of the executions of Petri nets and time Petrinets. Occurrence nets is one of these partial order representations, and theirstructure directly provides the causality, conflict and concurrency relationsbetween events. However, we show that, even in the untimed case, some logicaldependencies between event occurrences are not directly described by thesestructural relations. After having formalized these logical dependencies, wesolve the following synthesis problem: from a formula that describes a set ofruns, we build an associated occurrence net. Then we study the logicalrelations in a simplified timed setting and show that time creates complexdependencies between event occurrences. These dependencies can be used to definea canonical unfolding, for this particular timed setting.

Cette thèse étudie les différentes facettes du risque de liquidité et analyse le rôle essentiel qu'elles jouent dans la stabilité systémique.Dans la partie théorique de la thèse, nous traitons du risque de liquidité au travers des ruées bancaires. Progressivement, nous introduisons le marché interbancaire en tant que mécanisme d'assurance de liquidité entre les banques. Cependant, lorsqu'il y a une pénurie globale de liquidité, ce marché a tendance à favoriser la propagation d'une crise de liquidité de banque à banque, ce qui peut aboutir au risque systémique. Nous étudions de manière approfondie la littérature sur la contagion par les liens interbancaires et au travers des prix des actifs. / This thesis examines the different facets of the liquidity risk and aims to analyse their essential role in the stability of the financial system. In the theoretical part of the thesis, we treat liquidity risk through bank runs. Gradually, we introduce the interbank market as a liquidity insurance mechanism between banks. However, when there is an overall shortage of liquidity, this market tends to encourage the spread of liquidity crises from bank to bank which can lead to a systemic financial crisis. We study the literature on risk contagion by interbank links and through asset price effects. The applied part of the thesis aims to test the validity of hypotheses and insights presented in the theoretical framework. The goal is to betterunderstand the mechanism of liquidity risk and the forces of interaction between balance sheet effects that can lead to the transformation of liquidity risk into systemic risk caused by counterparty risk or the revaluation of tradable assets at market prices. In the first numerical application, we propose to evaluate the risk of contagion by interbank linkages in a context where banks borrow on the interbank market and/or at the central bank if necessary. The second simulation is dedicated to contagion through asset price effects, considering that the banks must sell assets on the market to meet their liquidity shortfall. If mark-to-market accounting is applied, the effects of the douwnturn in prices appear immediately and cause a spontaneous reaction from stakeholders.

Cette thèse cherche à intégrer une conception riche de l'information à l'étude des ruées bancaires et de la contagion informationnelle. Elle s'intéresse à la détection de l'insolvabilité bancaire et à l'initiation des procédures de résolution. Le premier chapitre est une revue de la littérature sur les ruées bancaires s'intéressant du modèle "canonique" de Diamond & Dybvig (1983, J Pol Econ 91 (3): 401-19) et ses alternatives. Le second chapitre traite des théories de la contagion financière. Puis, la thèse propose une réinterprétation de ces deux littératures s'intéressant aux propriétés qualitatives de l'information produite par l'apprentissage endogène. La seconde partie est consacrée aux conséquences de cette réinterprétation pour le droit bancaire. D'abord, des parallèles sont tracés entre les ruées bancaires et le modèle de la "négociation des créanciers" de la théorie de l'insolvabilité. L'analyse positive suggère qu'il satisfait mieux la littérature empirique, et l'analyse normative que les "négociations des créanciers" sont mieux gérées par les institutions de la faillite d'entreprise plutôt que par les résolutions administratives. Ensuite, ces apports sont utilisés pour une analyse comparative institutionnelle des régimes de faillite des grandes institutions financières non bancaires américaines s'appuyant sur les principes de la Robust Political Economy. La thèse présente deux résultats principaux. Les crises informationnelles bancaires produisent l'information nécessaire à leurs résolutions. L'initiation des procédures de résolution de l'insolvabilité par le débiteur peut être un mécanisme robuste dans certains des cas étudiés. / This dissertation seeks to integrate a rich conception of information in the study of bank runs and informational contagion. In particular, it is interested in the detection of bank insolvency and the initiation of insolvency resolution procedures.The first chapter is a review of the literature on bank runs focused on the "canonical" model of Diamond & Dybvig (1983, J Pol Econ 91 (3): 401-19) and its alternatives. The second chapter deals with the theories of financial contagion. Then the dissertation proposes a reinterpretation of these two literatures focusing on the qualitative properties of the information produced by endogenous learning.The second part deals with the consequences of this reinterpretation for banking law. First, parallels are drawn between bank runs and the "creditors' bargain" model of bankruptcy theory. The positive analysis suggests that it better satisfies the empirical literature, and normative analysis that "creditor bargains" are better managed by the institutions of corporate bankruptcy than administrative resolutions. Then, these contributions are used for a comparative institutional analysis of bankruptcy regimes large US non-bank financial institutions based on the principles of Robust Political Economy.The thesis has two main results. Informational banking crises produce the information necessary for their own resolutions. The initiation of insolvency resolution procedures by the debtor can be a robust mechanism in some of the cases studied.

Cette thèse vise à étudier certains modèles biologiques dans le réseau neuronal et dans la chimiotaxie avec la méthode d’analyse spectrale. Afin de traiter les principaux problèmes, tels que l’existence et l’unicité des solutions et des états stationnaires ainsi que les comportements asymptotiques, le modèle linéaire ou linéarisé associé est considéré par l’aspect du spectre et des semi-groupes dans les espaces appropriés, puis la stabilité de modèle non linéaire suit. Plus précisément, nous commençons par une équation de courses-et-chutes linéaire dans la dimension d≥1 pour établir l’existence d’un état stationnaire unique, positif et normalisé et la stabilité exponentielle asymptotique dans l’espace L¹ pondéré basé sur la théorie de Kerin-Rutman avec quelques estimations du moment de la théorie cinétique. Ensuite, nous considérons le modèle du temps écoulé sous les hypothèses générales sur le taux de tir et nous prouvons l’unicité de l’état stationnaire et sa stabilité exponentielle non linéaire en cas sans ou avec délai au régime de connectivité faible de la théorie de l’analyse spectrale pour les semi-groupes. Enfin, nous étudions le modèle sous une hypothèse de régularité plus faible sur le taux de tir et l’existence de la solution ainsi que la même stabilité exponentielle sont généralement établies n’importe la prise en compte du délai ou non, au régime de connectivité faible ou forte. / This thesis is aimed to study some biological models in neuronal network and chemotaxis with the spectral analysis method. In order to deal with the main concerning problems, such as the existence and uniqueness of the solutions and steady states as well as the asymptotic behaviors, the associated linear or linearized model is considered from the aspect of spectrum and semigroups in appropriate spaces then the nonlinear stability follows. More precisely, we start with a linear runs-and-tumbles equation in dimension d≥1 to establish the existence of a unique positive and normalized steady state and the exponential asymptotic stability in weighted L¹ space based on the Krein-Rutman theory together with some moment estimates from kinetic theory. Then, we consider time elapsed model under general assumptions on the firing rate and prove the uniqueness of the steady state and its nonlinear exponential stability in case without or with delay in the weak connectivity regime from the spectral analysis theory for semigroups. Finally, we study the model under weaker regularity assumption on the firing rate and the existence of the solution as well as the same exponential stability are established generally no matter taking delay into account or not and no matter in weak or strong connectivity regime.