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Uso de small worlds no roteamento em redes de sensores sem fio / Use of small worlds in wireless sensor networks routingLuz, Giulian Dalton 10 May 2007 (has links)
Neste trabalho foi realizado um estudo sobre o uso e influências do efeito small world, ou seis graus de separação, no roteamento de redes de sensores sem fio (RSSFs). Para esse objetivo, foram analisadas as características das RSSFs que influenciam no roteamento e os diferentes tipos de protocolos. Além disso, foram estudadas as características do efeito small world e suas propriedades, de um modo geral, em redes de larga escala e com alta densidade de nós, incluindo o modelo de small world para o estudo de redes ad hoc. Realizou-se um breve estudo sobre redes overlay, redes lógicas criadas sobre a rede física com o propósito de melhorar suas qualidades e seu desempenho. A conclusão neste trabalho é que small worlds pode ser empregado para melhorar o funcionamento de protocolos de roteamento em RSSFs. / In this work, has made an study about the use and influences of the small world effect, or six degrees of separation, in routing of wireless sensors network (WSNs). For this objective, was analyzed the characteristics of WSNs that influence in the routing and the different types of protocols. Moreover, was studied the characteristics of small world effect and it properties, generically, in large scale networks with a high node density, including the small world model for the study of ad hoc networks. Was accomplished a brief study about overlay networks, logical network created over physical network with the purpose of improve qualities and performance. The conclusion in this work is that small worlds can be applied to improve the operation of WSNs routing protocols.
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Uso de small worlds no roteamento em redes de sensores sem fio / Use of small worlds in wireless sensor networks routingGiulian Dalton Luz 10 May 2007 (has links)
Neste trabalho foi realizado um estudo sobre o uso e influências do efeito small world, ou seis graus de separação, no roteamento de redes de sensores sem fio (RSSFs). Para esse objetivo, foram analisadas as características das RSSFs que influenciam no roteamento e os diferentes tipos de protocolos. Além disso, foram estudadas as características do efeito small world e suas propriedades, de um modo geral, em redes de larga escala e com alta densidade de nós, incluindo o modelo de small world para o estudo de redes ad hoc. Realizou-se um breve estudo sobre redes overlay, redes lógicas criadas sobre a rede física com o propósito de melhorar suas qualidades e seu desempenho. A conclusão neste trabalho é que small worlds pode ser empregado para melhorar o funcionamento de protocolos de roteamento em RSSFs. / In this work, has made an study about the use and influences of the small world effect, or six degrees of separation, in routing of wireless sensors network (WSNs). For this objective, was analyzed the characteristics of WSNs that influence in the routing and the different types of protocols. Moreover, was studied the characteristics of small world effect and it properties, generically, in large scale networks with a high node density, including the small world model for the study of ad hoc networks. Was accomplished a brief study about overlay networks, logical network created over physical network with the purpose of improve qualities and performance. The conclusion in this work is that small worlds can be applied to improve the operation of WSNs routing protocols.
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La colaboración científica en la psicología social y de la personalidad: Análisis bibliométrico de la revista Journal of Personality and Social PsychologyPeñaranda Ortega, Maria 30 March 2004 (has links)
En este trabajo presentamos un análisis sobre la colaboración cientifica de la psicologia social y de la personalidad, configurada desde el Journal of Personality and Social Psychology (JPSP), desde su inicio en 1965, hasta el año 2000. Lo realizamos desde una doble perspectiva: un análisis cuantitativo bibliométrico y un análisis histórico descriptivo. Además, presentamos un análisis de la colaboración institucional y los colegios invisibles desde la teoria "Small Worlds". Desde la psicologia social y de la personalidad, analizamos las teorías y los autores más significativos para su desarrollo histórico en disciplinas cientificas, y las áreas más relevantes por las que discurren. Desde una perspectiva bibliométrica, se analizan las variables habituales para un estudio bibliométrico. Para el análisis de colaboración, nos basamos en el modelo "Small Worlds". Comprobamos que puede ser un instrumento muy útil para analizar la concentración en redes sociales" y en este caso, la colaboración cientifica. / In this research we present an analysis concerning the scientific collaboration of social and personality psychology, shaped from the Journal of Personality and Social Psychology (JPSP) since its beginning in 1965 until the year 2000. We made it from a double prospective: a bibliometric cuantitative analysis and a descriptive historical analysis of social and personality psychology. Moreover, we present an analysis of the insti tutional cooperation and the invisible colleges of the "Small Worlds" theory. We analyse the most significative theories and authors to its historical development in some scientific subjects and the most important areas in which they are developed. From a bibliometric prospective, usual options to make a bibliometric research are studied.
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Fenomén Almodóvar (Prolínání "malých světů" v díle Pedra Almodóvara) / Phenomenon Almodóvar (The Interdigitation of "Small Worlds" in the Work of Pedro Almodóvar)Turčan, Jakub January 2013 (has links)
CHARLES UNIVERSITY IN PRAGUE FACULTY OF HUMANITIES Department of Electronic Culture and Semiotics Bc. Jakub Turčan Phenomenon Almodóvar (The Interdigitation of "Small Worlds" in the Work of Pedro Almodóvar) Thesis Supervisor: Mgr. Josef Fulka, Ph.D. Thesis Abstract Prague 2013 Abstract The paper focuses on the problem of authorship by means of an in-depth analysis of the film work of the Spanish director Pedro Almodóvar. The analysis is preceded by setting the author's work in the context of its origin, introduction of its so far existing content, as well as the concepts this work employs. Due to the hypertextual character of this postmodern oeuvre, the study is based on the concept of small worlds by Umberto Eco, hence the worlds of fiction with limited content in comparison to the actual world. The complete film work is perceived as a self- contained, yet within its character an ever open Text. The interdigitation of its small worlds is understood as a series of intratextual references, however the work also monitors its intertextual and, as a blend of these two, the transtextual content. Presenting the directors unique signature, combining several known approaches of the film creation with his own style- constituting elements, the analysis adduces the auteurist character - first described by the film...
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Réseaux lexicaux, métaphore, acquisition : une approche interdisciplinaire et inter-linguistique du lexique verbal / Lexical networks, Metaphor, Acquisition : an interdisciplinary and interlinguistic approach of verb lexiconDesalle, Yann 18 May 2012 (has links)
Souvent, lorsque les locuteurs d'une langue n'ont pas accès à l'item conventionnel pour étiqueter un objet ou un événement, ils étendent, consciemment ou inconsciemment, le sens d'un autre item lexical disponible. Ce phénomène se produit particulièrement au cours de la phase d'acquisition lexicale des jeunes enfants. Lorsqu'une telle sur-extension sémantique va au-delà de la catégorie d'objet ou d'événement conventionnellement dénotée par l'item lexical produit, il s'agit d'une sur-extension catégorielle et l'énoncé produit est d'allure métaphorique: par exemple, « déshabiller la pomme » pour l'action peler une pomme est un énoncé d'allure métaphorique. Tout d'abord, cette thèse a permis de développer SLAM, un système de résolution lexicale automatique des métaphores produites en situation de manque du mot. SLAM s'appuie, d'une part, sur l'analyse syntaxique de grands corpus et, d'autre part, sur la structure Petit Monde Hiérarchique des réseaux lexicaux de synonymie. Par exemple, à partir des énoncés « elle déshabille* la pomme » ou « les bras* de l'arbre », SLAM permet d'obtenir les interprétations suivantes: respectivement, « elle pèle une pomme » et « les branches de l'arbre ».Ensuite, cette thèse a permis d'étudier spécifiquement la dynamique d'acquisition du lexique des verbes qui se stabilise après celui des noms. D'une part, des outils méthodologiques pour l'étude inter-linguistique de la dynamique d'acquisition du lexique des verbes ont été élaborés: (a) un cadre méthodologique pour la construction de procédures d'identification des sur-extensions sémantiques catégorielles des verbes; (b) une méthodologie pour le repérage des stimuli visuels d'action sans biais culturel. D'autre part, les liens entre la structure des réseaux lexicaux de synonymie et la dynamique d'acquisition du lexique des verbes en français et en mandarin ont été mis au jour. Après avoir pointé des différences dans la dynamique d'acquisition du lexique des verbes par les jeunes enfants natifs du français et du mandarin, cette étude a servi à construire le score REFLEX, mesure du degré d'acquisition du lexique des verbes, qui permet de catégoriser automatiquement les jeunes enfants vs adultes en français et en mandarin. / When speakers have no access to the conventional label for an object or an event, they tend to extend, consciously or not, the meaning of another available lexical label. This phenomenon often occurs during the lexical acquisition stage of young children. When a such overextension goes beyond the conventional object or event category denoted by the produced label, it is a categorical overextension and the produced utterance is metaphorical: for instance, ``to undress an apple'' for the action to peel an apple is metaphorical.During this thesis, I developed SLAM, a computational system that automatically gives lexical solutions to metaphors filling a lexical gap. SLAM is based on a syntactic analysis of large corpora and on the Hierarchical Small World structure of synonymy networks. For instance, when the produced utterances are ``elle déshabille* une pomme'' ( ``she undresses* an apple'') or ``les bras* de l'arbr'' (``the arms* of the tree''), SLAM gives the interpretations here after: respectively, ``elle pèle une pomme'' (``she peels an apple'') and ``les branches de l'arbre'' (``the branches of the tree'').Then, I studied the dynamics of verb lexicon acquisition that is longer than noun lexicon acquisition. On the one hand, I built methodological tools for inter-linguistic studies of the dynamics of verb lexicon acquisition: (a) a methodological frame to build procedures to identify categorical overextensions of verbs; (b) a methodology to detect visual stimuli containing actions without cultural bias. On the other hand, I highlighted the links between the structure of synonymy networks and the dynamics of verbs lexicon acquisition in french and mandarin. This study has indicated differences in dynamics of verb lexicon acquisition between french and mandarin native speakers. Finally, I built REFLEX, a score that indicates the degree of verb lexicon acquisition and automatically categorizes young children vs adults in french and mandarin.
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Stability and Control in Complex Networks of Dynamical SystemsManaffam, Saeed 01 January 2015 (has links)
Stability analysis of networked dynamical systems has been of interest in many disciplines such as biology and physics and chemistry with applications such as LASER cooling and plasma stability. These large networks are often modeled to have a completely random (Erdös-Rényi) or semi-random (Small-World) topologies. The former model is often used due to mathematical tractability while the latter has been shown to be a better model for most real life networks. The recent emergence of cyber physical systems, and in particular the smart grid, has given rise to a number of engineering questions regarding the control and optimization of such networks. Some of the these questions are: How can the stability of a random network be characterized in probabilistic terms? Can the effects of network topology and system dynamics be separated? What does it take to control a large random network? Can decentralized (pinning) control be effective? If not, how large does the control network needs to be? How can decentralized or distributed controllers be designed? How the size of control network would scale with the size of networked system? Motivated by these questions, we began by studying the probability of stability of synchronization in random networks of oscillators. We developed a stability condition separating the effects of topology and node dynamics and evaluated bounds on the probability of stability for both Erdös-Rényi (ER) and Small-World (SW) network topology models. We then turned our attention to the more realistic scenario where the dynamics of the nodes and couplings are mismatched. Utilizing the concept of ε-synchronization, we have studied the probability of synchronization and showed that the synchronization error, ε, can be arbitrarily reduced using linear controllers. We have also considered the decentralized approach of pinning control to ensure stability in such complex networks. In the pinning method, decentralized controllers are used to control a fraction of the nodes in the network. This is different from traditional decentralized approaches where all the nodes have their own controllers. While the problem of selecting the minimum number of pinning nodes is known to be NP-hard and grows exponentially with the number of nodes in the network we have devised a suboptimal algorithm to select the pinning nodes which converges linearly with network size. We have also analyzed the effectiveness of the pinning approach for the synchronization of oscillators in the networks with fast switching, where the network links disconnect and reconnect quickly relative to the node dynamics. To address the scaling problem in the design of distributed control networks, we have employed a random control network to stabilize a random plant network. Our results show that for an ER plant network, the control network needs to grow linearly with the size of the plant network.
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Information Culture and Belief Formation in Religious CongregationsFreeburg, Darin S. 09 December 2013 (has links)
No description available.
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Saripod : système multi-Agent de Recherche Intelligente POssibiliste de Documents Web / Saripod : an Intelligent Possibilistic Web Information Retrieval using Multiagent systemElayeb, Bilel 26 June 2009 (has links)
La présente thèse de doctorat en informatique propose un modèle pour une recherche d'information intelligente possibiliste des documents Web et son implémentation. Ce modèle est à base de deux Réseaux Petits Mondes Hiérarchiques (RPMH) et d'un Réseau Possibiliste (RP) : Le premier RPMH consiste à structurer les documents retrouvés en zones denses de pages Web thématiquement liées les unes aux autres. Nous faisons ainsi apparaître des nuages denses de pages qui traitent d'un sujet et des sujets connexes (assez similaires sémantiquement) et qui répondent toutes fortement à une requête. Le second RPMH est celui qui consiste à ne pas prendre les mots-clés tels quels mais à considérer une requête comme multiple en ce sens qu'on ne cherche pas seulement le mot-clé dans les pages Web mais aussi les substantifs qui lui sont sémantiquement proches. Les Réseaux Possibilistes combinent les deux RPMH afin d'organiser les documents recherchés selon les préférences de l'utilisateur. En effet, l'originalité du modèle proposé se décline selon les trois volets suivants qui synthétisent nos contributions. Le premier volet s'intéresse au processus itératif de la reformulation sémantique de requêtes. Cette technique est à base de relations de dépendance entre les termes de la requête. Nous évaluons notamment les proximités des mots du dictionnaire français « Le Grand Robert » par rapport aux termes de la requête. Ces proximités sont calculées par le biais de notre approche de recherche des composantes de sens dans un RPMH de dictionnaire de mots par application d'une méthode basée sur le dénombrement des circuits dans le réseau. En fait, l'utilisateur du système proposé choisit le nombre de mots sémantiquement proches qu'il désire ajouter à chaque terme de sa requête originelle pour construire sa requête reformulée sémantiquement. Cette dernière représente la première partie de son profil qu'il propose au système. La seconde partie de son profil est constituée des choix des coefficients de pertinence possibilistes affectés aux entités logiques des documents de la collection. Ainsi, notre système tient compte des profils dynamiques des utilisateurs au fur et à mesure que ces derniers utilisent le système. Ce dernier est caractérisé par son intelligence, son adaptativité, sa flexibilité et sa dynamicité. Le second volet consiste à proposer des relations de dépendance entre les documents recherchés dans un cadre ordinal. Ces relations de dépendance entre ces documents traduisent les liens sémantiques ou statistiques évaluant les distributions des termes communs à des paires ou ensembles de documents. Afin de quantifier ces relations, nous nous sommes basés sur les calculs des proximités entres ces documents par application d'une méthode de dénombrement de circuits dans le RPMH de pages Web. En effet, les documents peuvent ainsi être regroupés dans des classes communes (groupes de documents thématiquement proches). Le troisième volet concerne la définition des relations de dépendance, entre les termes de la requête et les documents recherchés, dans un cadre qualitatif. Les valeurs affectées à ces relations traduisent des ordres partiels de préférence. En fait, la théorie des possibilités offre deux cadres de travail : le cadre qualitatif ou ordinal et le cadre quantitatif. Nous avons proposé notre modèle dans un cadre ordinal. Ainsi, des préférences entre les termes de la requête se sont ajoutées à notre modèle de base. Ces préférences permettent de restituer des documents classés par préférence de pertinence. Nous avons mesuré aussi l'apport de ces facteurs de préférence dans l'augmentation des scores de pertinence des documents contenant ces termes dans le but de pénaliser les scores de pertinence des documents ne les contenant pas. Pour la mise en place de ce modèle nous avons choisi les systèmes multi-agents. L'avantage de l'architecture que nous proposons est qu'elle offre un cadre pour une collaboration entre les différents acteurs et la mise en œuvre de toutes les fonctionnalités du système de recherche d'information (SRI). L'architecture s'accorde parfaitement avec le caractère intelligent possibiliste et permet de bénéficier des capacités de synergie inhérente entre les différentes composantes du modèle proposé. Dans le présent travail, nous avons donc pu mettre en exergue à travers les expérimentations effectuées l'intérêt de faire combiner les deux RPMH via un réseau possibiliste dans un SRI, ce qui permet d'enrichir le niveau d'exploration d'une collection. Ce dernier n'est pas limité aux documents mais l'étend en considérant les requêtes. En effet, la phase de reformulation sémantique de requête permet à l'utilisateur de profiter des autres documents correspondants aux termes sémantiquement proches des termes de la requête originelle. Ces documents peuvent exister dans d'autres classes des thèmes. En conséquence, une reclassification proposée par le système s'avère pertinente afin d'adapter les résultats d'une requête aux nouveaux besoins des utilisateurs. / This Ph.D. thesis proposes a new model for a multiagent possibilistic Web information retrieval and its implementation. This model is based on two Hierarchical Small-Worlds (HSW) Networks and a Possibilistic Networks (PN): The first HSW consists in structuring the founded documents in dense zones of Web pages which strongly depend on each other. We thus reveal dense clouds of pages which "speak" more or less about the same subject and related subjects (semantically similar) and which all strongly answer user's query. The second HSW consists in considering the query as multiple in the sense that we don't seek only the keyword in the Web pages but also its semantically close substantives. The PN generates the mixing of these two HSW in order to organize the searched documents according to user's preferences. Indeed, the originality of the suggested model is declined according to three following shutters' which synthesize our contributions. The first shutter is interested in the iterative process of query semantic reformulation. This technique is based on relationship dependence between query's terms. We evaluate in particular the semantics proximities between the words of the French dictionary "Le Grand Robert" and query's terms. These proximities are calculated via our approach of research of the semantics components in the HSW of dictionary of words by application of our method of enumeration of circuits in the HSW of dictionary. In fact, the user of the suggested system chooses the number of close words that he desire to add to each word of his initial query to build his semantically reformulated query. This one represents the first part of user's profile which he proposes to the system. The second part of its profile makes up of its choices of the coefficients of relevance possibilistic of the logical entities of the documents of the collection. Thus, our system takes account of the dynamic profiles of its users progressively they use the system, which proves its intelligence, its adaptability, its flexibility and its dynamicity. The second shutter consists in proposing relationship dependence between documents of the collection within an ordinal framework. These relationships dependence between these documents represent the semantic or statistical links evaluating the distributions of the general terms to pairs or sets of documents. In order to quantify these relationships, we are based on the calculations of the proximities between these documents by application of a method enumerating of circuits in the HSW of Web pages. Indeed, the documents can thus be clustered in common classes (groups of close documents). The third shutter is related to the definition of the relationships dependence between query's terms and documents of the collection, within a qualitative framework. The assigned values to these relations translate preferably partial orders. In fact, possibilistic theory offers two working frameworks: the qualitative or ordinal framework and the numerical framework. We proposed our model within an ordinal framework. Thus, we add to our basic model preferences between query's terms. These preferences make it possible to restore documents classified by relevance's preference. We also measured the contribution of these preferably factors in the increase of the relevance's scores of documents containing these terms with an aim of penalizing the relevance's scores of the documents not containing them. For the installation of this model we chose multiagent systems. The advantage of the proposed architecture is that it offers a framework for collaboration between the various actors and the implementation of all the functionalities of the information retrieval system. Architecture agrees perfectly with the possibilistic intelligent character and makes it possible to profit from the capacities of inherent synergy in the suggested model. We thus could put forward, through the carried out experiments, the goal of combining the two HSW via a possibilistic network in an information retrieval system, which makes it possible to enrich the exploration level of a collection. This exploration is not only limited to the documents but it extends by considering also the query. Indeed, the semantic query reformulation phase makes it possible to benefit user from other documents which contain some close terms of the initial query. These documents can exist in other topics classes. Consequently, a reclassification suggested by the system proves its relevance in order to adapt query's results to new user's needs.
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Ensaios em board interlockingBarros, Thiago de Sousa 19 December 2017 (has links)
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Previous issue date: 2017-12-19 / Nos últimos anos, o tema da governança ganhou relevância no contexto corporativo, muito em função da proliferação de empresas multinacionais, do desenvolvimento dos mercados de capitais e do crescente número de investidores. Neste cenário, os Conselhos de Administração das firmas, figuras centrais para o cumprimento das funções de monitoramento, exercício das boas práticas de governança e proteção dos acionistas, vêm sendo estudados tanto no meio empresarial, quanto na esfera acadêmica. Tendo em consideração que a forma, o perfil e a independência do Conselho de Administração podem afetar as decisões tomadas pelas companhias, especialmente quanto as questões financeiras de investimento, além de impactar no desempenho das firmas e possibilitar a elas maior ou menor acesso a informações e recursos, esta tese almejou investigar o board interlocking – que é quando um conselheiro ocupa assento em mais de uma empresa –, característica usualmente notada nos mercados globais. Todavia, na literatura financeira contemporânea tem havido evidências empíricas antagônicas quanto aos reais benefícios e prejuízos advindos do uso dessa estratégia de deter Conselhos de Administração interligados, seja através de conselheiros compartilhados ou via interlocking político. Em face desses resultados discrepantes observados e para cumprir com os objetivos de pesquisa delineados, três ensaios foram desenvolvidos e integram este trabalho. O primeiro, utilizando uma amostra com 153 empresas brasileiras para a série 2000-2015, associa a temática do board interlocking com as operações de fusões e aquisições, uma vez que este pode ser um meio utilizado para reduzir assimetria informacional e custos de coleta, afetando a participação em M&As. Em adição e por meio de uma amostra de 174 firmas brasileiras, o segundo ensaio – observando que dentro de uma rede de empresas podem ocorrer formações de mundos pequenos (Small Worlds), grupos estes em que a informação circularia ainda de forma mais célere entre seus membros – investigou a existência desses Small Worlds na rede de firmas brasileiras, considerando o período 2000-2015, e sua influência nos processos de fusões e aquisições. Por fim, o terceiro ensaio, tendo por base uma amostra de companhias brasileiras e contemplando na análise os quatro últimos pleitos eleitorais ocorridos no Brasil (2002, 2006, 2010 e 2014), focalizou a relação entre interlocking político, medido através de doações de campanhas eleitorais e conselheiros com background político, e as previsões dos analistas, utilizando como proxy o custo de capital implícito. Os resultados do primeiro ensaio sugerem que firmas com maior degree, isto é, companhias que mantêm maior número de laços com outras, por meio de conselhos interligados, têm maior probabilidade de realizar fusões e aquisições. O segundo ensaio possibilita inferir que há formação de Small World nas redes anuais de empresas, dado o alto coeficiente de agrupamento e a baixa distância média entre as firmas. Contudo, os resultados sinalizam que o mundo pequeno não afeta significativamente a concretização de M&As, levando em consideração as fusões e aquisições no âmbito nacional e internacional. Por último, o terceiro ensaio evidencia que as doações para campanhas eleitorais, no cenário brasileiro, podem gerar efeitos negativos e os analistas de mercado avaliarem esse tipo de interlocking político como algo de maior risco, o que ocasiona, por conseguinte, maior custo de capital implícito para as empresas. Em contrapartida, deter no board conselheiros com background político não demonstrou relação significante, com exceção do período de Crise Fiscal (medido pela dummy PIB negativo e que compreendeu o hiato temporal 2014- 2015), quando os analistas precificaram o background político como algo negativo, elevando, portanto, o custo de capital implícito. / Governance has become a relevant topic within the corporate context in recent years, largely because of the proliferation of multinational companies, the development of capital markets and the growing number of investors. In this scenario, company Boards of Directors, which are central figures when it comes to complying with monitoring functions, exercising good governance practices and protecting shareholders, have been the object of study in both the business environment and the academic sphere. The shape, profile and independence of the Board of Directors can affect the decisions that companies take, especially with regard to financial investment issues. Such aspects can also have an impact on company performance and enable firms to have greater or lesser access to information and resources. The aim of this thesis, therefore, is to investigate board interlocking, a situation in which a director has a seat on the boards of more than one company, a characteristic normally seen in global markets. Some of the empirical evidence in contemporary financial literature, however, is antagonistic as far as concerns the real benefits and losses arising from the use of this strategy of having interconnected Boards of Directors, either by way of shared directors, or political interlocking. In view of these discrepant results and to comply with the research objectives that were outlined, three tests were developed and form part of this work. The first one, using a sample of 153 Brazilian companies for the 2000-2015 series, associates board interlocking with mergers and acquisitions, since this can be a way of reducing information asymmetry and collection costs, thus affecting participation in M&As. Small World formations may occur within a network of companies; these are groups in which information circulates even faster among members. The second test, therefore, involved a sample of 174 Brazilian firms and investigated the existence of these Small Worlds in the network of Brazilian firms, considering the period 2000-2015, and the influence of these Small Worlds on merger and acquisition processes. Finally, the third test, based on a sample of Brazilian companies and considering the last four presidential elections in Brazil (2002, 2006, 2010 and 2014), focused on the relationship between political interlocking, as measured by election campaign donations and directors with a political background, and the forecasts of analysts, using as a proxy the implicit cost of capital. The results of the first test suggest that firms with a higher degree, in other words, companies that have a greater number of ties with others by way of interconnected boards are more likely to become involved in mergers and acquisitions. The second test makes it possible to infer that Small Worlds are formed in annual company networks, given the high clustering coefficient and small average distance between firms. Taking into consideration both Brazilian and international mergers and acquisitions, the results, however, indicate that a Small World does not have a significant effect on the carrying out of M&As. Finally, the third test shows that donations to electoral campaigns in the Brazilian context can generate negative effects. Market analysts consider that there is greater risk with this type of political interlocking, which consequently leads to a higher implied cost of capital for the companies. On the other hand, having board members with a political background did not prove to have a significant relationship, except during the fiscal crisis period (as measured by the negative GDP dummy and which included the 2014-2015 hiatus) when analysts "priced" political background as being a negative factor, thus raising the implicit cost of capital.
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