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En undersökning av faktorer som styr valet mellan XP och RUPFlisberg, Magnus January 2005 (has links)
<p>För att genomföra ett lyckat systemutvecklingsprojekt kan ett flertal utvecklingsmetoder användas. Utvecklingsmetoder hjälper till att undvika fallgropar under utvecklingsprocessen. De två typer av utvecklingsprocesser som arbetet baseras på är eXtreme Programming (XP) och Rational Unified Process (RUP).</p><p>Genom att identifiera skillnader samt hur XP och RUP kan kombineras, presenteras olika faktorer. En faktor är projektstorlek som enligt litteratur är den viktigaste faktorn vid valet mellan XP och RUP. Med hjälp av en enkätundersökning hos ett antal utvecklingsföretag har data samlats in för att ta reda på om projektstorlek är en huvudsaklig faktor för valet mellan XP och RUP. Undersökningen resulterar i att verifiera eller falsifiera om projektstorlek är en huvudsaklig faktor vid valet mellan XP och RUP. Undersökningen visar med hjälp av ett poängsystem att projektstorlek inte är den huvudsakliga faktorn, det vill säga att hypotesen om att projektstorlek är huvudsaklig, falsifieras</p>
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Essays on discrete choice under social interaction methodology and applications /Li, Ji, January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 95-99).
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A Ritual in Perspective: An Ethnographic Analysis of a Lakota Sundance At Hoosier National ForestHardy, Gabor 01 May 2012 (has links)
AN ABSTRACT OF THE DISSERTATION OF Gabor Hardy, for the Doctor of Philosophy degree in Speech Communication, presented on 8 March, 2012, at Southern Illinois University Carbondale TITLE: A RITUAL IN PERSPECTIVE: AN ETHNOGRAPHIC ANALYSIS OF A LAKOTA SUNDANCE AT HOOSIER NATIONAL FOREST MAJOR PROFESSOR: Dr. Jonathan Gray Using ethnographic methods, interviews, observations, and participation of and in indigenous rituals, I discuss the ways in which Western and American Indian notions of spirit, human beings and their place in the world, and the practice of spirituality differ in action, thought, and word. Since the time of the Renaissance the supremacy of "rational" or "reasonable" modes of thinking has influenced the modern world. Many American Indian writers, shamans, and Sundance chiefs believe that an understanding of their approach to the Divine may never be apprehended without some sort of actual experience. This indigenous perspective differs in substantial ways from hegemonic, Christian and Western linear modes of thinking. I draw on my attendance at numerous Sundance rituals, readings by American Indian spiritual leaders, and ethnographic work done at the Salt Creek Sundance ritual to articulate and streamline major differences and similarities that exist in both approaches. Through participation and dialogue, a distinct indigenous spiritual approach emerges that is difficult to reconcile with traditional Christian and Eurocentric world views. As I hope to demonstrate, the appearance and performance of American Indian ritual serve to not only challenge Western colonial perspectives, but also to empower indigenous approaches to spirit. In order to cultivate a more tolerant approach to the diversity and various modes of spiritual expression, a change in consciousness is needed, not necessarily for the American Indian worldview, but from the current ethnocentric worldview of the US Government which holds this form of government as the highest accomplishment of any nation thus far. This dissertation offers an approach that probes the relationship between an earth based religion and a monotheistic religion. Finally, I present a vision that allows for an understanding and/or appreciation of a spiritual approach which remains alien to Western approaches and conceptualizations of spirit. Key words: rational mind, symbolic meaning, ritual, myths, sacred, ideology, truth, indigenous worlds, cosmology, spirituality, reason, ethnography, Sundance, performance, and Native American.
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Controvérsias : persuasão racional na ciênciaOliveira, Rúbia Liz Vogt de January 2011 (has links)
Diferentemente do que alegam visões idealizadas da ciência, as controvérsias não são fenômenos marginais na história da ciência, mas o âmbito próprio do desenvolvimento crítico do saber científico. As interações polêmicas são campo de atividade da racionalidade científica. Partindo do exame da tricotomia de tipos de polêmicas de Marcelo Dascal – constituída por discussão, disputa e controvérsia – objetiva-se caracterizar as polêmicas e traçar relações entre elas, especialmente no que tange às suas respectivas racionalidades. A proposta não se restringe a apontar consensos e dissensos entre a racionalidade dura da discussão, a irracionalidade da disputa e a racionalidade branda da controvérsia; tenciona-se o “diálogo entre racionalidades”. A interação entre as racionalidades – preservando as características de cada racionalidade, pois não se projeta reduzir uma racionalidade à outra –, possibilita o alargamento do escopo de atuação das racionalidades. A tricotomia de tipos de Marcelo Dascal escapa a tendência de dicotomização do par discussão/disputa, o qual foi tradicionalmente tido por exaustivo. Sob tal perspectiva, a controvérsia se apresenta como uma via alternativa. A racionalidade branda conduz a persuasão racional – objetivo da controvérsia. A controvérsia permite, ainda, a emergência de idéias inovadoras, o que faz dessa polêmica motor da ciência. Marcello Pera opera uma volta a Aristóteles para resgatar a função cognitiva que retórica e dialética desempenham na argumentação persuasiva da ciência. Para Pera, o foco na argumentação persuasiva da ciência revela aspectos da prática científica que foram esquecidos pelas propostas tradicionais (metodologistas) e que não receberam tratamento adequado de propostas contemporâneas (anti-metodologistas). Segundo M. Pera, o desafino das opiniões sobre a descrição e a explicação dos fatos alegadamente recorrentes do desalinho entre os fatos do mundo e as descrições do mundo gera as polêmicas na ciência. A racionalidade persuasiva empregada nas interações polêmicas visa ao convencimento não apenas dos contendores, mas também da comunidade concernente ao debate. A prática de uma argumentação persuasiva da ciência é o ponto-chave para a confluência das idéias de Marcelo Dascal e Marcello Pera. Em decorrência desses novos entendimentos acerca da ciência, emerge uma nova visão da racionalidade científica: mais flexível, sensível aos papéis da audiência e do contexto e valorada no seu empenho cognitivo. Essa racionalidade, abordada desde um ponto de vista humano, permite a emersão de conclusões razoáveis ou convincentes. / Unlike idealized views of science claim, controversies are not marginal phenomena in the history of science but the proper domain of scientific knowledge’s critical development. Polemical exchange are the field of activity of scientific rationality. Based on the exam of the Marcelo Dascal’s trichotomy of polemical exchange types – consisting of discussion, dispute and controversy – the objective is to characterize the controversy and to trace the relations between them, especially in regard to their respective rationalities. The proposal is not restricted to pointing out consensus and disagreements among the hard rationality of the discussion, the irrationality of the dispute and the soft rationality of controversy. The "dialogue between rationalities” is aimed. The interaction between rationalities – preserving the characteristics of each rationality, since it is not projected to reduce one rationality into the other – makes it possible to extend the scope of work of rationalities. The trichotomy of types of M. Dascal escapes from the tendency to dichotomization of the pair discussion/dispute, which is traditionally regarded as exhaustive. Controversy is presented as an alternative way between hard rationality and irrationality. The soft rationality leads rational persuasion – the proper aim of controversy. Controversy also allows the emergence of innovative ideas, which makes this polemic the engine of science. Marcello Pera turns back to Aristotle to rescue the cognitive function that rhetoric and dialectic play in the persuasive argumentation of science. For Pera, the focus on the persuasive argumentation of science reveals aspects of scientific practice that have been overlooked by traditional proposals (methodologists) and that have not received proper treatment from contemporary proposals (anti-methodologists). According to M. Pera, polemics in science are generated by the missmatch between descriptions fail to capture the facts. The persuasive rationality employed in polemical interactions aims convincing not only the contenders, but also the community concerning the debate. The practice of a persuasive argumentation in science is the key point for the confluence of the ideas from Marcelo Dascal and Marcello Pera. Due to these new understandings about science, a new and more flexible vision of scientific rationality emerge: one, which is sensitive to the role of audience and context in cognitive appraisals. As approached from a human point of view, this new rationality allows the emergence of convincing or reasonable conclusions.
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CONSTITUTING THE POLITICAL: A PHENOMENOLOGICAL PERSPECTIVE ON POLITICAL LIBERALISMPontin, Fabricio 01 December 2013 (has links)
In this thesis I will attempt to develop a phenomenological account for Political Liberalism. My hypothesis is that a re-articulation of the main issues in transcendental phenomenology as it relates to social philosophy, first in a genetic sense (as developed by Alfred Schutz), but also in a generative context (as developed by Bernhard Waldenfels), provides us with a methodological ground that can instigate a more complex account for the questions of social choice and the way in which we establish preferences. My thesis is that such a complex account of social choice can motivate us to focus on the disordered nature of our constitution of preferences, and point at the importance of a deep comprehension of historicity, along with a defense of freedom of speech as a tool for resignification of social values.
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Strategic choices in realistic settingsWang, Rongyu January 2016 (has links)
In this thesis, we study Bayesian games with two players and two actions (2 by 2 games) in realistic settings where private information is correlated or players have scarcity of attention. The contribution of this thesis is to shed further light on strategic interactions in realistic settings. Chapter 1 gives an introduction of the research and contributions of this thesis. In Chapter 2, we study how the correlation of private information affects rational agents’ choice in a symmetric game of strategic substitutes. The game we study is a static 2 by 2 entry game. Private information is assumed to be jointly normally distributed. The game can, for some parameter values, be solved by a cutoff strategy: that is enter if the private payoff shock is above some cutoff value and do not enter otherwise. Chapter 2 shows that there is a restriction on the value of correlation coefficient such that the game can be solved by the use of cutoff strategies. In this strategic-substitutes game, there are two possibilities. When the game can be solved by cutoff strategies, either, the game exhibits a unique (symmetric) equilibrium for any value of correlation coefficient; or, there is a threshold value for the correlation coefficient such that there is a unique (symmetric) equilibrium if the correlation coefficient is below the threshold, while if the correlation coefficient is above the threshold value, there are three equilibria: a symmetric equilibrium and two asymmetric equilibria. To understand how parameter changes affect players’ equilibrium behaviour, a comparative statics analysis on symmetric equilibrium is conducted. It is found that increasing monopoly profit or duopoly profit encourages players to enter the market, while increasing information correlation or jointly increasing the variances of players’ prior distribution will make players more likely to choose entry if the equilibrium cutoff strategies are below the unconditional mean, and less likely to choose entry if the current equilibrium cutoff strategies are above the unconditional mean. In Chapter 3, we study a 2 by 2 entry game of strategic complements in which players’ private information is correlated. As in Chapter 2, the game is symmetric and private information is modelled by a joint normal distribution. We use a cutoff strategy as defined in Chapter 2 to solve the game. Given other parameters, there exists a critical value of the correlation coefficient. For correlation coefficient below this critical value, cutoff strategies cannot be used to solve the game. We explore the number of equilibria and comparative static properties of the solution with respect to the correlation coefficient and the variance of the prior distribution. As the correlation coefficient changes from the lowest feasible (such that cutoff strategies are applicable) value to one, the sequence of the number of equilibrium will be 3 to 2 to 1, or 3 to 1. Alternatively, under some parameter specifications, the game exhibits a unique equilibrium for all feasible value of the correlation coefficient. The comparative statics of equilibrium strategies depends on the sign of the equilibrium cutoff strategies and the equilibrium’s stability. We provide a necessary and sufficient condition for the existence of a unique equilibrium. This necessary and sufficient condition nests the sufficient condition for uniqueness given by Morris and Shin (2005). Finally, if the correlation coefficient is negative for the strategic-complements games or positive for the strategic-substitutes games, there exists a critical value of variance such that for a variance below this threshold, the game cannot be solved in cutoff strategies. This implies that Harsanyi’s (1973) purification rationale, supposing the perturbed games are solved by cutoff strategies and the uncertainty of perturbed games vanishes as the variances of the perturbation-error distribution converge to zero, cannot be applied for a strategic-substitutes (strategic-complements) game with dependent perturbation errors that follow a joint normal distribution if the correlation coefficient is positive (negative). However, if the correlation coefficient is positive for the strategic-complements games or negative for the strategic-substitutes games, the purification rationale is still applicable even with dependent perturbation errors. There are Bayesian games that converge to the underlying complete information game as the perturbation errors degenerate to zero, and every pure strategy Bayesian Nash equilibrium of the perturbed games will converge to the corresponding Nash equilibrium of the complete information game in the limit. In Chapter 4, we study how scarcity of attention affects strategic choice behaviour in a 2 by 2 incomplete information strategic-substitutes entry game. Scarcity of attention is a common psychological characteristic (Kahneman 1973) and it is modelled by the rational inattention approach introduced by Sims (1998). In our game, players acquire information about their own private payoff shocks (which here follows a high-low binary distribution) at a cost. We find that, given the opponent’s strategy, as the unit cost of information acquisition increases a player’s best response will switch from acquiring information to simply comparing the ex-ante expected payoff of each action (using the player’s prior). By studying symmetric Bayesian games, we find that scarcity of attention can generate multiple equilibria in games that ordinarily have a unique equilibrium. These multiple equilibria are generated by the information cost. In any Bayesian game where there are multiple equilibria, there always exists one pair of asymmetric equilibria in which at least one player plays the game without acquiring information. The number of equilibria differs with the value of the unit information cost. There can be 1, 5 or 3 equilibria. Increasing the unit information cost could encourage or discourage a player from choosing entry. It depends on whether the prior probability of a high payoff shock is greater or less than some threshold value. We compare the rational inattention Bayesian game with a Bayesian quantal response equilibrium game where the observation errors are additive and follow a Type I extreme value distribution. A necessary and sufficient condition is established such that both the rational inattention Bayesian game and quantal response game have a common equilibrium.
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A Defense of TransitivityJanuary 2015 (has links)
abstract: This thesis seeks to defend transitivity as a rational constraint on preferences against two putative counterexamples to transitivity. This thesis is divided into three sections. In the first section, I consider two famous and popular arguments in defense of transitivity and argue they are insufficient to adequately defend transitivity. I then outline a desiderata for successful arguments in defense of transitivity and identify some basic assumptions I will be making throughout the thesis. In section two, I consider the first putative counterexample to transitivity: Quinn’s Puzzle of the Self-Torturer. I offer two plausible interpretations of Quinn’s puzzle and argue that both fail. One because it does not genuinely induce intransitive preferences, and the other because the situation it requires is logically impossible. I conclude this section by defending my arguments against known objections in the literature. Finally, in the third section, I consider a counterexample to transitivity from Larry Temkin that has received little attention in the literature. I argue that while the initial counterexample is unpersuasive it can be augmented and made into a more forceful argument. I then argue that this improved counterexample fails due to some erroneous assumptions prevalent in the literature on incomparability. I conclude the thesis with a brief summary and some closing remarks. / Dissertation/Thesis / Masters Thesis Philosophy 2015
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Controvérsias : persuasão racional na ciênciaOliveira, Rúbia Liz Vogt de January 2011 (has links)
Diferentemente do que alegam visões idealizadas da ciência, as controvérsias não são fenômenos marginais na história da ciência, mas o âmbito próprio do desenvolvimento crítico do saber científico. As interações polêmicas são campo de atividade da racionalidade científica. Partindo do exame da tricotomia de tipos de polêmicas de Marcelo Dascal – constituída por discussão, disputa e controvérsia – objetiva-se caracterizar as polêmicas e traçar relações entre elas, especialmente no que tange às suas respectivas racionalidades. A proposta não se restringe a apontar consensos e dissensos entre a racionalidade dura da discussão, a irracionalidade da disputa e a racionalidade branda da controvérsia; tenciona-se o “diálogo entre racionalidades”. A interação entre as racionalidades – preservando as características de cada racionalidade, pois não se projeta reduzir uma racionalidade à outra –, possibilita o alargamento do escopo de atuação das racionalidades. A tricotomia de tipos de Marcelo Dascal escapa a tendência de dicotomização do par discussão/disputa, o qual foi tradicionalmente tido por exaustivo. Sob tal perspectiva, a controvérsia se apresenta como uma via alternativa. A racionalidade branda conduz a persuasão racional – objetivo da controvérsia. A controvérsia permite, ainda, a emergência de idéias inovadoras, o que faz dessa polêmica motor da ciência. Marcello Pera opera uma volta a Aristóteles para resgatar a função cognitiva que retórica e dialética desempenham na argumentação persuasiva da ciência. Para Pera, o foco na argumentação persuasiva da ciência revela aspectos da prática científica que foram esquecidos pelas propostas tradicionais (metodologistas) e que não receberam tratamento adequado de propostas contemporâneas (anti-metodologistas). Segundo M. Pera, o desafino das opiniões sobre a descrição e a explicação dos fatos alegadamente recorrentes do desalinho entre os fatos do mundo e as descrições do mundo gera as polêmicas na ciência. A racionalidade persuasiva empregada nas interações polêmicas visa ao convencimento não apenas dos contendores, mas também da comunidade concernente ao debate. A prática de uma argumentação persuasiva da ciência é o ponto-chave para a confluência das idéias de Marcelo Dascal e Marcello Pera. Em decorrência desses novos entendimentos acerca da ciência, emerge uma nova visão da racionalidade científica: mais flexível, sensível aos papéis da audiência e do contexto e valorada no seu empenho cognitivo. Essa racionalidade, abordada desde um ponto de vista humano, permite a emersão de conclusões razoáveis ou convincentes. / Unlike idealized views of science claim, controversies are not marginal phenomena in the history of science but the proper domain of scientific knowledge’s critical development. Polemical exchange are the field of activity of scientific rationality. Based on the exam of the Marcelo Dascal’s trichotomy of polemical exchange types – consisting of discussion, dispute and controversy – the objective is to characterize the controversy and to trace the relations between them, especially in regard to their respective rationalities. The proposal is not restricted to pointing out consensus and disagreements among the hard rationality of the discussion, the irrationality of the dispute and the soft rationality of controversy. The "dialogue between rationalities” is aimed. The interaction between rationalities – preserving the characteristics of each rationality, since it is not projected to reduce one rationality into the other – makes it possible to extend the scope of work of rationalities. The trichotomy of types of M. Dascal escapes from the tendency to dichotomization of the pair discussion/dispute, which is traditionally regarded as exhaustive. Controversy is presented as an alternative way between hard rationality and irrationality. The soft rationality leads rational persuasion – the proper aim of controversy. Controversy also allows the emergence of innovative ideas, which makes this polemic the engine of science. Marcello Pera turns back to Aristotle to rescue the cognitive function that rhetoric and dialectic play in the persuasive argumentation of science. For Pera, the focus on the persuasive argumentation of science reveals aspects of scientific practice that have been overlooked by traditional proposals (methodologists) and that have not received proper treatment from contemporary proposals (anti-methodologists). According to M. Pera, polemics in science are generated by the missmatch between descriptions fail to capture the facts. The persuasive rationality employed in polemical interactions aims convincing not only the contenders, but also the community concerning the debate. The practice of a persuasive argumentation in science is the key point for the confluence of the ideas from Marcelo Dascal and Marcello Pera. Due to these new understandings about science, a new and more flexible vision of scientific rationality emerge: one, which is sensitive to the role of audience and context in cognitive appraisals. As approached from a human point of view, this new rationality allows the emergence of convincing or reasonable conclusions.
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Controvérsias : persuasão racional na ciênciaOliveira, Rúbia Liz Vogt de January 2011 (has links)
Diferentemente do que alegam visões idealizadas da ciência, as controvérsias não são fenômenos marginais na história da ciência, mas o âmbito próprio do desenvolvimento crítico do saber científico. As interações polêmicas são campo de atividade da racionalidade científica. Partindo do exame da tricotomia de tipos de polêmicas de Marcelo Dascal – constituída por discussão, disputa e controvérsia – objetiva-se caracterizar as polêmicas e traçar relações entre elas, especialmente no que tange às suas respectivas racionalidades. A proposta não se restringe a apontar consensos e dissensos entre a racionalidade dura da discussão, a irracionalidade da disputa e a racionalidade branda da controvérsia; tenciona-se o “diálogo entre racionalidades”. A interação entre as racionalidades – preservando as características de cada racionalidade, pois não se projeta reduzir uma racionalidade à outra –, possibilita o alargamento do escopo de atuação das racionalidades. A tricotomia de tipos de Marcelo Dascal escapa a tendência de dicotomização do par discussão/disputa, o qual foi tradicionalmente tido por exaustivo. Sob tal perspectiva, a controvérsia se apresenta como uma via alternativa. A racionalidade branda conduz a persuasão racional – objetivo da controvérsia. A controvérsia permite, ainda, a emergência de idéias inovadoras, o que faz dessa polêmica motor da ciência. Marcello Pera opera uma volta a Aristóteles para resgatar a função cognitiva que retórica e dialética desempenham na argumentação persuasiva da ciência. Para Pera, o foco na argumentação persuasiva da ciência revela aspectos da prática científica que foram esquecidos pelas propostas tradicionais (metodologistas) e que não receberam tratamento adequado de propostas contemporâneas (anti-metodologistas). Segundo M. Pera, o desafino das opiniões sobre a descrição e a explicação dos fatos alegadamente recorrentes do desalinho entre os fatos do mundo e as descrições do mundo gera as polêmicas na ciência. A racionalidade persuasiva empregada nas interações polêmicas visa ao convencimento não apenas dos contendores, mas também da comunidade concernente ao debate. A prática de uma argumentação persuasiva da ciência é o ponto-chave para a confluência das idéias de Marcelo Dascal e Marcello Pera. Em decorrência desses novos entendimentos acerca da ciência, emerge uma nova visão da racionalidade científica: mais flexível, sensível aos papéis da audiência e do contexto e valorada no seu empenho cognitivo. Essa racionalidade, abordada desde um ponto de vista humano, permite a emersão de conclusões razoáveis ou convincentes. / Unlike idealized views of science claim, controversies are not marginal phenomena in the history of science but the proper domain of scientific knowledge’s critical development. Polemical exchange are the field of activity of scientific rationality. Based on the exam of the Marcelo Dascal’s trichotomy of polemical exchange types – consisting of discussion, dispute and controversy – the objective is to characterize the controversy and to trace the relations between them, especially in regard to their respective rationalities. The proposal is not restricted to pointing out consensus and disagreements among the hard rationality of the discussion, the irrationality of the dispute and the soft rationality of controversy. The "dialogue between rationalities” is aimed. The interaction between rationalities – preserving the characteristics of each rationality, since it is not projected to reduce one rationality into the other – makes it possible to extend the scope of work of rationalities. The trichotomy of types of M. Dascal escapes from the tendency to dichotomization of the pair discussion/dispute, which is traditionally regarded as exhaustive. Controversy is presented as an alternative way between hard rationality and irrationality. The soft rationality leads rational persuasion – the proper aim of controversy. Controversy also allows the emergence of innovative ideas, which makes this polemic the engine of science. Marcello Pera turns back to Aristotle to rescue the cognitive function that rhetoric and dialectic play in the persuasive argumentation of science. For Pera, the focus on the persuasive argumentation of science reveals aspects of scientific practice that have been overlooked by traditional proposals (methodologists) and that have not received proper treatment from contemporary proposals (anti-methodologists). According to M. Pera, polemics in science are generated by the missmatch between descriptions fail to capture the facts. The persuasive rationality employed in polemical interactions aims convincing not only the contenders, but also the community concerning the debate. The practice of a persuasive argumentation in science is the key point for the confluence of the ideas from Marcelo Dascal and Marcello Pera. Due to these new understandings about science, a new and more flexible vision of scientific rationality emerge: one, which is sensitive to the role of audience and context in cognitive appraisals. As approached from a human point of view, this new rationality allows the emergence of convincing or reasonable conclusions.
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Learning in DSGE macroeconomics / Aprendizado em macroeconomia DSGEIgor Velecico 22 November 2013 (has links)
In this thesis we analyze learning mechanisms applied to a variety of macroeconomic models. In the first chapter, we present and discuss the advantages and limitations of estimating Dynamic Stochastic General Equilibrium (DSGE) models added with learning, thus suppressing the central assumption of rational expectations. First, we introduce the reader on how learning can be inserted in those models, starting from the discussion of where and how the rational expectations operator is substituted by the learning mechanism. We then present several additional learning setups related to the information set available to agents considered by the literature, which affect directly the dynamics of the final model. Last, we estimate three different models to assess the advantages of learning in our artificially generated data and real data for Brazil. In the second chapter, we algebraically show the limitations of learning and propose two flexible methods to deal with the parameter instability in data. The first of these methods is closely related to the DSGE-VAR methodology, which we call Learning DSGE-VAR, and the second, which departs even further from the DSGE model, which we call Learning Minimum State Variable, or LMSV. Finally, in the third chapter we provide evidences that the supposedly moderate improvements found in the previous chapters have more to do with the nature of the model at hand than to the learning method itself. To do so, we simulate problems using a time-varying structure similar to the one presented in chapter 1 and evaluate the likelihood improvements with different learning mechanisms. We then provide empirical evidences of learning in reduced form models to forecast inflation, interest rates and output gap for the Brazilian economy, using ad-hoc reduced form models commonly used by practitioners. / Nesta tese analisamos os instrumentos de aprendizado (Learning) aplicados a uma variedade de modelos macroeconômicos. Em nosso primeiro capítulo, apresentamos e discutimos as vantagens e limitações de se estimar modelos dinâmicos e estocásticos de equilíbrio geral (DSGE) acrescidos de um mecanismo de aprendizado, ou seja, abandonando-se a hipótese de expectativas racionais, tão cara a estes modelos. Em primeiro lugar, mostramos como esse mecanismo pode ser introduzido nesses modelos, começando pela discussão de onde e como o operador de expectativas racionais é substituído pelo operador de aprendizado. Em seguida apresentamos configurações alternativas em relação ao conjunto de informações disponível aos agentes dentro do mecanismo de aprendizado, que afeta diretamente a dinâmica do modelo final a ser estimado. Por fim, estimamos três modelos usando nosso mecanismo de aprendizado, aplicando-o a dados artificiais e reais para a economia brasileira. No segundo capítulo, mostramos algebricamente as limitações do mecanismo de aprendizado em modelos DSGE e propomos dois métodos mais flexíveis para lidar com a instabilidade dos parâmetros nos dados. O primeiro desses métodos é intimamente ligado à literatura de DSGEVAR, e que chamamos de Learning DSGE-VAR, enquanto o segundo método, que se afasta ainda mais do modelo DSGE, ao qual chamamos de LMSV. No terceiro capítulo, provemos evidências de que os ganhos supostamente moderados de nosso modelo de aprendizado apresentados nos dois primeiros capítulos têm mais a ver com a natureza dos modelos estimados do que com o método de aprendizado utilizado. Para tal, simulamos dois grupos de dados usando uma estrutura econômica que varia no tempo, semelhante àquela estudada no primeiro capítulo, e estimamos os modelos utilizando diferentes mecanismos de aprendizado. Por fim, fornecemos evidências empíricas de aprendizado em modelos de forma reduzida para projetar inflação, taxas de juros e hiato do produto para a economia brasileira, através de modelos ad-hoc comumente utilizado por econometristas.
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