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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Industrial organization dynamics : bounded capabilities and technological interfaces of the Brazilian shipbuilding and Offshore Industry

Alves, André Cherubini January 2015 (has links)
O progresso tecnológico e a inovação são geralmente aceitos como propulsores do desenvolvimento econômico das nações. No entanto, a compreensão quanto aos mecanismos subjacentes ao desenvolvimento ainda parece ser um desafio tanto para pesquisa quanto para a formulação de políticas públicas. Isso requer uma avaliação empírica na forma como a atividade econômica é criada e absorvida pelos diferentes agentes econômicos dando a forma e escopo da organização industrial em uma região ou setor. Tendo com base a teoria evolucionária da mudança técnica e na teoria dos custos de transação, organização industrial é definida como relações econômicas de complementaridades tecnológicas onde as firmas estabelecem interfaces tecnológicas com outras em função dos seus próprios limites. A forma com que firmas lidam com os seus próprios limites, irá determinar o potencial dinâmico da organização industrial. Está pesquisa visa responder a seguinte pergunta: o que determina a forma e o escopo da indústria e sua dinâmica subjacente? Para responder essa questão, este estudo irá analisar os recentes desenvolvimentos da Indústria da construção naval brasileira e offshore Brasileira onde, nos últimos anos, houve uma grande mobilização institucional para viabilizar o catch-up de tecnologia e competitividade no setor. O cenário recente de construção e ampliação de capacidades das empresas em uma indústria complexa permite observar a dinâmica da organização industrial por meio da análise das interfaces tecnológicas. A pesquisa traz uma revisão da dinâmica e evolução da indústria naval nos principais polos produtores do mundo e, posteriormente, parte para a análise detalhada do desenvolvimento de da indústria no Brasil através da descrição do conjunto de interfaces tecnológicas e relações industriais inerentes ao arranjo de um grande estaleiro. Os resultados mostram que, apesar da elaboração de políticas que visam favorecer o desenvolvimento do setor, a indústria depende da capacidade dos diversos agentes econômicos absorverem os conhecimentos necessários e dar coesão às interfaces tecnológicas. Paradoxalmente, precede à geração de uma dinâmica industrial, buscar dar estabilidade às interfaces tecnológicas com o intuito de acelerar o processo de aprendizagem. Isso depende da integração dos diferentes atores envolvidos. Embora o estaleiro analisado detenha os ativos específicos que denotam um potencial competitivo, o mesmo busca superar os limites de conhecimento por meio da intensificação de transferência de tecnologia que lhe permita utilizar as tecnologias e, principalmente, dar fluxos e rotinas necessárias para operar de forma mais eficiente. Apesar do ambiente institucional favorável que deu origem ao ressurgimento do setor, a janela de oportunidade criada pelas instituições é limitada. Portanto, o setor precisa encontrar maneiras de aprender mais rápido, porém é preciso escolher mecanismos que economizem nos custos de construção de capacidades. Dado os limites das capacidades das empresas brasileiras, mecanismos de transferência de tecnologia parecem ser uma das principais estratégias para reduzir esses custos. / Technological progress and Innovation are generally accepted as the fundamental phenomenon of economic development of nations. However, understanding the underlying mechanisms behind 'development' still seems to be a challenge. This requires an empirical assessment into the way economic activity is created and distributed across firms and markets giving the shape and scope of industrial organization. Drawing on evolutionary and transaction costs, industrial organization is defined as economic relations of technological complementarities where bounded capabilities connect through technological interfaces. The way firms and markets deal with their capability boundedness will determine the dynamic potential that can be generated in the economic system. This research begins by asking what determines shape and scope of industries and its underlying dynamics? In order to address this question, this thesis will analyze the recent developments of the Brazilian Shipbuilding and Offshore Industry where government has put in place an entire institutional arrangement to boost industrial/market competitiveness and technological catch-up in the hopes of generating economic development. The scenario of a re-emerging complex sector where the capabilities of firms are under construction, allows the examination of the dynamics behind the organization of the industry through the analysis the different technological interfaces involved. The research begins by first analyzing the evolution and dynamics of the shipbuilding sector worldwide and later, it explores the recent shape, scope and dynamics of the Brazilian Shipbuilding Industry by assessing, describing and analyzing the set of technological interfaces and bounded capabilities found at one shipyard. Results show that despite of the policies designed to promote the development of the sector, the industry depends on the ability of the various economic agents absorb the necessary knowledge and give cohesion to technological interfaces. Paradoxically, project stability seems to precede industrial dynamics in order to accelerate learning process and effectively succeed in catching-up. It depends on the internal and external integration of the different actors involved. While the analyzed site has current specific assets that denote a competitive potential, it sought to overcome the limits of knowledge through the intensification of technology transfer. Instability at the interfaces play against learning. This is increasingly improving through the intensification of knowledge transfer with the international partner. Despite the favorable institutional environment intended to provide the industry with some time to catch up, the window of opportunity created by it may not be long enough. Therefore, the industry needs to find a way to learn faster. Technological transfer mechanisms should be used to reduce the costs of building capabilities.
152

Verificação de programas C++ baseados no framework crossplataforma Qt

Garcia, Mário Angel Praia 13 September 2016 (has links)
Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2017-02-07T17:47:31Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação - Mário A. P. Garcia.pdf: 1777955 bytes, checksum: bbc5f97c856505f518492e5c8ec65c28 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2017-02-07T17:47:47Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação - Mário A. P. Garcia.pdf: 1777955 bytes, checksum: bbc5f97c856505f518492e5c8ec65c28 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2017-02-07T17:48:08Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação - Mário A. P. Garcia.pdf: 1777955 bytes, checksum: bbc5f97c856505f518492e5c8ec65c28 (MD5) / Made available in DSpace on 2017-02-07T17:48:08Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação - Mário A. P. Garcia.pdf: 1777955 bytes, checksum: bbc5f97c856505f518492e5c8ec65c28 (MD5) Previous issue date: 2016-09-13 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The software development for embedded systems is getting faster and faster, which generally incurs an increase in the associated complexity. As a consequence, consumer electronics companies usually invest a lot of resources in fast and automatic verification mechanisms, in order to create robust systems and reduce product recall rates. In addition, further development-time reduction and system robustness can be achieved through cross-platform frameworks, such as Qt, which favor the reliable port of software stacks to different devices. Based on that, the present work proposes a simplified version of the Qt framework, which is integrated into a checker based on satisfiability modulo theories (SMT), name as the efficient SMT-based bounded model checker (ESBMC++), for verifying actual Qt-based applications, and presents a success rate of 89%, for the developed benchmark suite. We also evaluate our simplified version of the Qt framework using other state-of-the-art verifiers for C++ programs and an evaluation about their level of compliance. It is worth mentioning that the proposed methodology is the first one to formally verify Qt-based applications, which has the potential to devise new directions for software verification of portable code. / O desenvolvimento de software para sistemas embarcados tem crescido rapidamente, o que na maioria das vezes acarreta em um aumento da complexidade associada a esse tipo de projeto. Como consequência, as empresas de eletrônica de consumo costumam investir recursos em mecanismos de verificação rápida e automática, com o intuito de desenvolver sistemas robustos e assim reduzir as taxas de recall de produtos. Além disso, a redução no tempo de desenvolvimento e na robustez dos sistemas desenvolvidos podem ser alcançados através de frameworks multi-plataformas, tais como Qt, que oferece um conjunto de bibliotecas (gráficas) confiáveis para vários dispositivos embarcados. Desta forma, este trabalho propõe uma versão simplificada do framework Qt que integrado a um verificador baseado nas teorias do módulo da satisfatibilidade, denominado Efficient SMT-Based Bounded Model Checker (ESBMC++), verifica aplicações reais que ultilizam o Qt, apresentando uma taxa de sucesso de 89%, para os benchmarks desenvolvidos. Com a versão simplificada do framework Qt proposto, também foi feita uma avaliação ultilizando outros verificadores que se encontram no estado da arte para verificação de programas em C++ e uma avalição a cerca de seu nível de conformidade. Dessa maneira, a metodologia proposta se afirma como a primeira a verificar formalmente aplicações baseadas no framework Qt, além de possuir um potencial para desenvolver novas frentes para a verificação de código portátil.
153

Vieses cognitivos e o investidor individual brasileiro: uma análise da intensidade de vieses em decisões de investidores / Cognitive biases and the Brazilian individual investor: the intensity of biases in investor\'s decisions

Bianca Simões Cotrim 17 November 2014 (has links)
O mercado de capitais brasileiro tem se desenvolvido ao longo dos anos, e com o fim do longo período inflacionário, houve a possibilidade das pessoas fazerem planejamentos de longo prazo, sem se preocupar apenas com a perda do valor do dinheiro no curto prazo. Alguns fatores levaram à entrada de investidores no mercado de capitais, que tem sido crescente nos últimos anos. Para que se atraia cada vez mais investidores para esse mercado, e de forma sustentável, instruindo-os para que possam ter mais consciência na hora de investir, é essencial conhecer vieses que influenciam suas decisões, pois, diferentemente do que apontam as Teorias Tradicionais e Modernas de Finanças, os investidores (e as pessoas em geral) não agem de forma completamente racional quando fazem escolhas, podendo ser influenciados, de forma mais ou menos intensa, por vieses, como excesso de confiança, falácia de custos irrecuperáveis, aversão à perda, entre outros, que poderão afetar essas escolhas, e por fim, o mercado em geral. Dessa forma, o objetivo deste estudo foi de identificar a intensidade em que vieses estão presentes em decisões de investidores individuais do mercado de capitais brasileiro, e verificar se essa intensidade está relacionada ao sexo e ao tempo como investidor do mercado, fornecendo subsídio para que sejam desenvolvidos programas, focados inicialmente naqueles vieses que se mostram mais presentes nas decisões, para instruir investidores e possíveis investidores sobre essa influência, ajudando-os a identificar padrões em suas escolhas que possam ser prejudiciais a eles. Para isso, o instrumento de pesquisa utilizado foi um questionário com questões múltipla escolha, disponibilizado em provedor de serviços de pesquisas eletrônicas, por meio do qual foi efetuada a coleta de dados. O link do questionário foi enviado a instituições relacionadas ao mercado de capitais para divulgação a investidores e a grupos de investidores por meio de redes sociais. No total, 178 pessoas responderam à pesquisa, sendo que 80 são investidores no mercado de capitais, cujas respostas foram analisadas. Para efetuar a interpretação das respostas foi utilizada análise descritiva. Observou-se que, dos 13 vieses analisados, apenas 4 se mostraram com alta intensidade na escolha de investidores, sendo eles os vieses de excesso de confiança, excesso de negociação, contabilização mental e ancoragem, e que, para maioria dos vieses não se observa diferença significativa de intensidade entre sexo masculino e feminino, mas é possível perceber que para alguns dos vieses quanto maior o tempo como investidor, menor a intensidade do viés. As respostas de não investidores também foram analisadas, como forma de identificar a intensidade em que vieses estariam presentes em pessoas que poderiam em algum momento ser investidores, e percebeu-se que, comparativamente aos investidores, eles apresentaram maior intensidade dos vieses. Para pessoas que estão envolvidas com o mercado de capitais a intensidade dos vieses não foi tão alta, mas para aqueles que não são investidores a alta intensidade foi predominante para um maior número de vieses, o que poderia estar relacionado à experiência adquirida no mercado de alguma forma, e que mostra a necessidade de apresentar situações a que as pessoas poderiam estar expostas e cuidados a serem tomados para mitigar as influências que podem sofrer ao investir no mercado. / The Brazilian capital market has developed over the years, and with the end of a long inflationary period, there was the possibility of people making long-term plans, instead of only being worried about the loss of value of money in the short term. Some factors have led to the entry of investors in the capital market, which has been growing in recent years. In order to attract more and more investors to this market, and in a sustainable way, instructing them so they can be more aware when investing, it is essential to know the biases that influence their decisions, since, unlike what the Traditional and Modern Finance Theories describe, investors (and people in general) do not act completely rationally when they make choices and may be influenced more or less intensely by biases such as overconfidence, sunk cost fallacy, loss aversion, among others, which may affect these choices, and ultimately, the market. Thus, the aim of this study was to identify the intensity in which biases are present in the decisions of individual investors in the Brazilian capital market, and verify if this intensity is related to sex and time as market investor, providing information so that programs can be developed, focused initially on those biases that are more present in decisions, to instruct investors and potential investors of this influence, helping them to identify patterns in their choices that may be harmful to them. For this, the research instrument was a questionnaire with multiple choice questions, available in electronic research services provider, through which was collected the data. The link to the questionnaire was sent to the capital market related institutions, so they could send it to investors, and groups of investors through social networks. 178 people responded to the survey, of which 80 are investors in the capital market, whose responses were analyzed. To analyze the responses it was used descriptive analysis. It was observed that, of the 13 biases analyzed, only 4 showed up with high intensity in the choice of investors, namely the bias of overconfidence, excessive trading, mental accounting and anchor, and that for, most biases, no significant difference in intensity is observed between males and females, however, for some biases, it is possible to see that when higher the period the person has been an investor, lower the intensity of the biases. The responses of non-investors were also analyzed as a way to identify the intensity in which biases were present in people who might be, at some point, investors, and it was noticed that, compared to investors, they showed greater intensity of biases. For those people who are involved with the capital market the intensity of biases was not as high as for those who are not, for whom the high intensity was prevalent for a larger number of biases. This could be related, somehow, to the experience gained in the market, and shows the need to present situations that people could be exposed and be careful about, being aware of steps that could be taken to mitigate the influences that they can suffer when investing in the market.
154

Improving the robustness with modified bounded homotopies and problem-tailored solving procedures

Malinen, I. (Ilkka) 11 January 2011 (has links)
Abstract The aim of this work is to improve the overall robustness in equation-oriented chemical engineering simulation work. Because the performance of locally convergent solving methods is strongly dependent on a favourable initial guess, bounded homotopy methods were investigated as a way to enlarge the domain of convergence. Bounded homotopies make it possible to keep the homotopy path inside a feasible problem domain. Thus the fatal errors possibly caused by unfeasible variable values in thermodynamic subroutines can be avoided. To enable the utilization of a narrow bounding zone, modifications were proposed for bounded homotopies. The performance of the modifications was studied with simple test problems and several types of distillation systems in the MATLAB environment. The findings illustrate that modified bounded homotopies with variables mapping make it possible to bound the homotopy path strictly to run inside a feasible problem domain. The homotopy path can be tracked accurately and flexibly also inside a narrow bounding zone. It was also noticed that by utilizing the concept of bounding the homotopy path with respect to the homotopy parameter, the possibility of approaching starting point and solution multiplicities is increased in cases where the traditional problem-independent homotopy method fails. The concept aims to connect separate homotopy path branches thus offering a trackable path with real space arithmetic. Even though the modified bounded homotopies were found to overcome several challenges often encountered with traditional problem-independent homotopy continuation methods, alone they are not enough to guarantee that the solution is approached from an arbitrary starting point. Therefore, problem-tailored solving procedures were implemented in the consideration of complex column configurations. Problem-tailored solving procedures aim to offer feasible consecutive sub-problems and thus direct the solving towards the state distribution that fulfils exact product purity specifications. As a whole, the modified bounded homotopies and problem-tailored solving procedures were found to improve the overall robustness of an equation-oriented solving approach. Thus the threshold for designing and implementing complex process systems such as complex distillation configurations for practical use could be lowered.
155

Le Lagrangien à l'épicerie : comparaison des résultats théoriques et empiriques du rendement de l'information sur Internet dans une perspective d'économie comportementale

Levasseur-Laberge, Cédric January 2017 (has links)
La prémisse de la rationalité décisionnelle des agents, généralement définie comme la « prise de décision optimale sous l’information disponible », occupe une place centrale dans la théorie économique, à tel point que, lorsque la rationalité décisionnelle passe à la loupe, c’est souvent l’ensemble de la science économique qui l’est à sa suite. Pourtant, le quotidien abonde de cas ne se conformant pas à une certaine définition de l’optimalité; pour des décisions de faibles enjeux, les agents économiques pourront couper court à leur réflexion et se contenter d’une décision potentiellement sous-optimale afin de minimiser le coût de la prise de décision. Or, avec l’ubiquité d’Internet, l’information et la puissance de calcul sont plus disponibles que jamais, à tel point où le tri de l’information dans la surabondance d’Internet constitue une nouvelle forme de coût de décision. Ce mémoire s’intéresse donc à deux questions concernant la prise de décision avec échéances; la première est: à quels types de décisions, en fonction de la taille de leur enjeu, les agents économiques consacreront-ils le plus de temps de réflexion? La seconde est: à quels types d’informations les agents se fient-ils le plus? Essentiellement, nous testons si les individus optimisent l’effort qu’ils mettent à optimiser . Nous utilisons une méthodologie expérimentale basée sur un jeu-questionnaire, avec incitatifs financiers à la performance, simulant différentes décisions à caractère économique auxquelles des personnes sont appelées à être exposées au cours de leur vie. Comme résultats, nous trouvons une relation concave entre la taille de l’enjeu sur lequel porte une décision et les ressources allouées à la décision. Cette relation s’estompe lorsque les contraintes de temps se resserrent. Nous tentons également de vérifier s’il existe un lien entre et le choix de sources d’informations à des fins de décision et la familiarité de celles-ci pour l’agent, mais ne trouvons pas de relation significative. De plus, nous ne parvenons pas à établir de relation entre le temps consacré à prendre une décision et l’optimalité de celle-ci.
156

Understanding Agency Problems in Headquarters-Subsidiary Relationships in Multinational Corporations: A contextualized Model.

Kostova, Tatiana, Nell, Phillip C., Hoenen, Anne Kristin January 2017 (has links) (PDF)
This paper proposes an agency model for headquarters subsidiary relationships in multinational organizations with headquarters as the principal and the subsidiary as the agent. As a departure from classical agency theory, our model is developed for the unit level of analysis and considers two root causes of the agency problem - self-interest and bounded rationality. We argue that in the organizational setting, one cannot assume absolute self-interest and perfect rationality of agents (subsidiaries) but should allow them to vary. We explain subsidiary level variation through a set of internal organizational and external social conditions in which the headquarters-subsidiary agency dyad is embedded. We then discuss several agency scenarios reflecting various levels of selfinterest and rationality that lead to different manifestations of the agency problem. The proposed framework can inform more relevant applications of the agency perspective in organizational studies and motivate future research.
157

Revisão de crenças em ACTL usando verificação de modelos limitada / Belief revision in ACTL using bounded model checking

Bruno Vercelino da Hora 03 August 2017 (has links)
Uma importante etapa do desenvolvimento de software é o de levantamento e análise dos requisitos. Porém, durante esta etapa podem ocorrer inconsistências que prejudicarão o andamento do projeto. Além disso, após finalizada a especificação, o cliente pode querer acrescentar ou modificar as funcionalidades do sistema. Tudo isso requer que a especificação do software seja revista, mas isso é altamente custoso, tornando necessário um processo automatizado para simplificar tal revisão. Para lidar com este problema, uma das abordagens utilizadas tem sido o processo de Revisão de Crenças, juntamente com o processo de Verificação de Modelos. O objetivo deste trabalho é utilizar o processo de revisão de crenças e verificação de modelos para avaliar especificações de um projeto procurando inconsistências, utilizando o fragmento universal da Computation Tree Logic (CTL), conhecido como ACTL, e revisá-las gerando sugestões de mudanças na especificação. A nossa proposta é traduzir para lógica clássica tanto o modelo (especificação do software) quanto a propriedade a ser revisada, e então aplicar um resolvedor SAT para verificar a satisfazibilidade da fórmula gerada. A partir da resposta do resolvedor SAT, iremos gerar sugestões válidas de mudanças para a especificação, fazendo o processo de tradução reversa da lógica clássica para o modelo original. / The objective of this work is to join the proccess of belief revision and model checking to evaluate project specifications looking for inconsistences, using the universal fragment of Computation Tree Logic (CTL), known as ACTL, and revise them generating changes suggestions in the specification. Our approach will translate the model (software specification) and the property to be revised to classical logic. Then we will apply a SAT solver to verify the generated formulas satsifability. From the SAT solver answer, we will create changes valid suggestions to the specification making the translation back from classical logic to the original model. To generate the changes suggestions, we proposed a framework based on heuristics where different approaches and decisions can be implemented, aiming a better application for each project scope. We implemented a basic heuristic as an example and used it to test the implementation to analise the proposed algorithm
158

A relevância da informação contábil para o mercado de capitais brasileiro sob o pressuposto da racionalidade limitada dos investidores / The relevance of accounting information for the Brazilian capital market under the assumption of bounded rationality of investors

Bruno Figlioli 18 August 2017 (has links)
A questão se a informação contábil é relevante para o mercado de capitais tem sido investigada, predominantemente, por meio dos pressupostos da Hipótese de Eficiência de Mercado (HEM). Para a HEM, toda informação relevante é refletida nos preços das ações de forma integral e instantânea, a partir da consideração de que as informações são analisadas e interpretadas por indivíduos plenamente racionais. Contudo, a literatura relacionada às áreas de Finanças Comportamentais e de Processos Decisórios tem indicado que os indivíduos, mesmo em condições de interação e de competição, como verificado nos mercados financeiros, são melhor caracterizados como detentores de racionalidade limitada ao tomar decisões. Nesse sentido, o objetivo deste estudo foi examinar a relevância da informação contábil para o mercado de capitais brasileiro sob o pressuposto da racionalidade limitada dos investidores. Para tanto, foram desenvolvidas escalas de complexidade específicas para as ações ordinárias e preferenciais. As escalas foram utilizadas como parâmetros para testar se níveis distintos de incertezas na estimação dos fluxos de caixa futuros estão associados à utilidade da informação contábil para o mercado de capitais. Além disso, no estudo, segregou-se a tomada de decisão nas dimensões dos ganhos e das perdas, tendo como objetivo identificar a relevância da informação contábil, segundo essa classificação. A amostra foi composta por informações de 232 empresas listadas na Bolsa de Valores, Mercadorias e Futuros de São Paulo (BM&FBOVESPA) no período de 2000 a 2015. Os resultados encontrados apontaram evidências de uma associação inversa entre os níveis de complexidade na avaliação das empresas e a relevância da informação contábil para os investidores. Foi identificado, também, que os preços das ações tendem a incorporar as informações contábeis relevantes de forma apenas gradual em condições de maiores níveis de incertezas. Esses resultados mostraram-se robustos para a dimensão dos ganhos. Além disso, os resultados obtidos sugerem que as normas contábeis do International Financial Reporting Standard (IFRS) reduziram os níveis de complexidade na avaliação das ações, o que resultou em um aumento da relevância da informação contábil para os investidores. De forma geral, as evidências obtidas corroboram a ideia de que os limites cognitivos dos indivíduos em processar informações pode ser um fator relacionado à magnitude com que os preços das ações refletem as informações contábeis. / The question whether accounting information is relevant to the capital market has been investigated predominantly through the assumptions of the Efficient Market Hypothesis (EMH). For EMH, all relevant information is reflected in stock prices in an integral and instantaneous way, considering that information is analyzed and interpreted by fully rational individuals. However, the literature related to the areas of Behavioral Finance and Decision Making has indicated that individuals, even in conditions of interaction and competition, as verified in financial markets, are better characterized as having limited rationality when making decisions. In this sense, the objective of this study was to examine the relevance of the accounting information to the Brazilian capital market, under the assumption of investors\' bounded rationality. Therefore, specific complexity scales were developed for common and preferred stocks. The scales were used as parameters to test if different levels of uncertainties in the estimation of future cash flows are associated with the usefulness of the accounting information for the capital market. In addition, the study segregated the decision making in gains and losses dimensions, aiming to identify the relevance of accounting information according to this classification. The sample consisted of information of 232 companies listed on the Brazilian Securities, Commodities and Futures Exchange (BM&FBOVESPA), from 2000 to 2015. The findings brought evidence of an inverse association between levels of complexity in the evaluation of the stocks and the relevance of accounting information to investors. It was identified that stock prices tend to incorporate the relevant accounting information only gradually in conditions of higher levels of uncertainties. These results were robust for the gain dimension. Furthermore, the results suggest that the accounting standards of International Financial Reporting Standard (IFRS) reduced complexity levels in stock valuation, which resulted in an increase in the relevance of accounting information for investors. In general, the evidence obtained corroborates with the idea that cognitive limits of individuals in processing information may be a factor related to the magnitude in which stock prices reflect the accounting information.
159

Operators on Continuous Function Spaces and Weak Precompactness

Abbott, Catherine Ann 08 1900 (has links)
If T:C(H,X)-->Y is a bounded linear operator then there exists a unique weakly regular finitely additive set function m:-->L(X,Y**) so that T(f) = ∫Hfdm. In this paper, bounded linear operators on C(H,X) are studied in terms the measure given by this representation theorem. The first chapter provides a brief history of representation theorems of these classes of operators. In the second chapter the represenation theorem used in the remainder of the paper is presented. If T is a weakly compact operator on C(H,X) with representing measure m, then m(A) is a weakly compact operator for every Borel set A. Furthermore, m is strongly bounded. Analogous statements may be made for many interesting classes of operators. In chapter III, two classes of operators, weakly precompact and QSP, are studied. Examples are provided to show that if T is weakly precompact (QSP) then m(A) need not be weakly precompact (QSP), for every Borel set A. In addition, it will be shown that weakly precompact and GSP operators need not have strongly bounded representing measures. Sufficient conditions are provided which guarantee that a weakly precompact (QSP) operator has weakly precompact (QSP) values. A sufficient condition for a weakly precomact operator to be strongly bounded is given. In chapter IV, weakly precompact subsets of L1(μ,X) are examined. For a Banach space X whose dual has the Radon-Nikodym property, it is shown that the weakly precompact subsets of L1(μ,X) are exactly the uniformly integrable subsets of L1(μ,X). Furthermore, it is shown that this characterization does not hold in Banach spaces X for which X* does not have the weak Radon-Nikodym property.
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Quatre essais sur la rationalité limitée en économie et finance comportementales / Four essays on bounded rationality in behavioral economics and finance

Duchêne, Sébastien 19 September 2017 (has links)
Cette thèse aborde le thème de la rationalité limitée à travers quatre chapitres, associant modèles théoriques, expériences en laboratoire et analyses statistiques et économétriques. Dans les deux premiers chapitres, nous testons la validité de nouveaux modèles en économie qui utilisent le formalisme mathématique de la mécanique quantique pour rendre compte de biais cognitifs. Au sein du chapitre 1, nous considérons des modèles expliquant l'effet d'ordre et en dérivons de nouvelles prédictions expérimentales. Dans le chapitre 2, nous proposons une expérience originale pour tester une large gamme de modèles quantiques qui rendent compte de l'erreur de conjonction. Les deux groupes de modèles échouent à nos tests empiriques. Nous discutons alors de possibles pistes d'améliorations de ces modèles. Le chapitre 3 explore la façon dont les individus traitent des informations économiques successives, complexes et abondantes. Nos résultats expérimentaux montrent l'inaptitude des sujets à combiner de telles informations, ce qui confirme la théorie de la trace floue. Enfin, le chapitre 4 relève de la finance expérimentale. Il étudie comment l'achat sur marge (respectivement la vente à découvert) augmente (diminue) le niveau des prix, la volatilité, l'hétérogénéité des marchés et les anticipations de prix des traders ainsi que la façon dont il modifie les stratégies de trading. Nos résultats mettent en évidence les nettes conséquences de chacune de ces techniques prises séparément, et identifient des phénomènes inattendus lorsqu'elles sont combinées. Nos analyses ouvrent la voie à une meilleure prise en compte de ces interactions déstabilisatrices par les autorités de régulation. / This thesis studies bounded rationality through four chapters, combining theoretical models, laboratory experiments and statistical and econometric analyzes. In the first two chapters, we test the validity of new models in economics which rely on the mathematical formalism of quantum mechanics to account for cognitive biases. In chapter 1, we consider models explaining the order effect and we derive new experimental predictions. In chapter 2, we propose an original experiment to test a wide range of quantum models that account for the conjunction fallacy. Both groups of models fail in our empirical tests and we then discuss possible ways to improve these models. The third chapter explores how individuals deal with successive, complex and abundant economic information. Our experimental results show the subjects' inability to combine such information, which confirms the fuzzy trace theory. Finally, the fourth chapter deals with experimental finance. It studies how margin buying (respectively short selling) increases (decreases) price levels, volatility, heterogeneity of markets, and traders' price expectations, as well as how it changes trading strategies. Our results highlight the clear consequences of each of these techniques used alone, and point to unexpected phenomena when both are combined. Regulatory authorities could take advantage of our analyzes to reduce the destabilization introduced by these techniques.

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