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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.
61

Fungerar kritisk realism i teori och praktik? : En studie om den kritiska realismens analytiska förmågor, med hjälp av en granskning av Tunnelkommissionens slutrapport

Urrutia Valdés, Erik January 2016 (has links)
Visionen med tunnelbygget i Hallandsåsen var att det skulle generera vinster på olika plan, men det kom mer att handla om snabba problemlösningar som inte alls blev tidseffektiva. Tunnelkommissionen analyserade problemen och släppte en slutrapport där lösningar föreslagits. Syftet med denna uppsats är att sammanfatta kritisk realism som en vetenskapsteori vars ontologiska och epistemologiska grunder skiljer sig från andra och som därmed behandlar teoretiska och praktiska aspekter annorlunda inom forskning. Därefter ska kritisk-realistiska angreppssätt analyseras i relation till Tunnelkommissionens slutrapport för att sedan kunna se om någon av dem reflekterar svagheter eller styrkor i olika anseenden. Resultatet av undersökningen visade att Tunnelkommissionen har svagheter i deras ställningstagande mot förståelser av grundläggande faktorer och endast finner lösningar som ur ett kritisk-realistiskt perspektiv skulle anses vara temporära. Kritisk realism däremot har svagheter i den bemärkelsen att det är svårt att komma fram med specifika tillvägagångssätt som reflekterar deras ontologiska och epistemologiska grunder i praktiken. Däremot visar denna undersökning att kritisk realism också förmedlar nya insikter inom forskning genom att förmedla nya grundläggande ställningstaganden.
62

Are Oil Prices Important to U.S. Manufacturers?

Schoff, Austin Perez 01 January 2017 (has links)
Very little has been written about the effect that oil prices have on manufacturing output in the United States. This paper aims to shed light about the effect of oil prices, oil imports, and GDP on U.S. manufacturing output through a four-variable vector autoregression and explain the timing of these shocks through impulse response functions. Empirical results find that oil prices are significant in determining manufacturing output, but manufacturing output is also significant in determining oil prices.
63

The Scharnhorst Effect: Superluminality and Causality in Effective Field Theories

de Clark, Sybil Gertrude, de Clark, Sybil Gertrude January 2016 (has links)
We present two re-derivations of the Scharnhorst effect. The latter was first obtained in 1990 by Klaus Scharnhorst, soon followed by Gabriel Barton, and consists in the theoretical prediction that the phase velocity of photons propagating in a Casimir vacuum normal to the plates would be larger than c. The first derivation given in the present work is relevant for the debates that have taken place in the physics literature regarding a possible greater-than-c value of the signal velocity. Indeed because the phase velocity result also held for the group velocity, the issue soon arose as to whether the same could be said for the signal velocity. Several arguments were presented against this notion, notably to the effect that measurement uncertainties would preclude such a measurement. These notably relied on the fact that the known phase velocity result is only valid within a certain frequency regime. Scharnhorst and Barton responded by arguing that given their previous result, the Kramers-Kronig relations imply one of two options: either the greater-than-c result holds for the signal velocity as well, or the Casimir vacuum behaves like an amplifying medium for some frequencies. Furthermore, the effect was later rederived and generalized within the framework of an effective metric approach, which has been argued to obviate the worries regarding causal paradoxes often associated with the possibility of faster-than-c signalling. However concerns related to theory errors as well as to the measurement uncertainties that had surfaced in the earlier debate have remained salient. By re-deriving the phase velocity using Soft-Collinear Effective Theory (SCET), one can address some of these concerns. Indeed, with regard to theory errors, SCET provides us with a framework where higher order corrections are known to be power-suppressed because SCET ensures that the expansion parameters are multiplied by factors of order 1. As a result, with due qualifications inherent to the nature of effective field theory, the result obtained within the SCET approach cannot be invalidated by higher order corrections. Furthermore, the theoretical description offered by SCET provides an argument relevant to the point that measurement uncertainties would prevent measuring the signal speed to be faster-than-c. Indeed, SCET implies the interaction between the Casimir vacuum and the propagating photon to be such that the latter would have the same phase velocity irrespective of its frequency. This in turn would entail that its signal velocity would be equal to this phase velocity, which is faster-than-c. The second calculation presented is concerned with the physical interpretation of the Scharnhorst effect, and constitutes an attempt at re-deriving it within source theory. Existing derivations imply that the Scharnhorst effect can be attributed to vacuum fluctuations. Other physical effects that share this feature have also been derived without any reference to the vacuum, but as due to source fields instead. We attempt a similar derivation for the Scharnhorst effect.
64

Les principaux déterminants de la dynamique du capital-risque / The main determinant of venture capital

Lounes, Malika 11 July 2012 (has links)
Cette thèse porte sur les déterminants fondamentaux du dynamisme du capital-risque. Notre démarche de recherche vise essentiellement à identifier les facteurs qui ont conduit au développement phénoménal de cette activité aux États-Unis et qui seraient susceptibles d'expliquer le retard de l'Europe en matière du capital-risque. On peut inférer de ce travail plusieurs conclusions. D'une part, l'existence d'un marché financier national dédié aux valeurs technologique ne peut être considérée comme le principal facteur expliquant l'avantage comparatif des États-Unis en termes du capital-risque. D'autre part, la demande et la performance anticipée constituent les fondements et la spécificité du capital-risque américain. Leur faiblesse dans les pays européens peut expliquer le retard de ces derniers. Nous avons également mis en évidence l'importance de l'environnement scientifique et technologique pour le dynamisme du capital-risque. Un résultat qui peut d'un coté, expliquer le retard des pays européens qui souffrent d'insuffisances en termes de dépenses en R&D. De l'autre, il peut rendre compte du succès de deux modèles de capital-risque basés sur la stratégie de recherche et développement, à savoir la Suède et Israël. / He thesis focuses on the determinants of venture capital dynamism. Our approach aims not only at identifying factors that led to the phenomenal development of this activity in the United States, but also at explaining why Europe still cannot catch up in terms of venture capital. Several conclusions can be inferred from this thesis. On the one hand, an active financial market cannot be regarded as the main factor explaining the comparative advantage of the U.S. in terms of venture capital. On the other hand, other more important factors may explain the superiority of U.S. venture capital as well as the European countries delay. Estimates conducted to highlight the importance of demand and of the expected performance for the venture capital dynamism. These two factors represent the strengths and the specificity of the U.S. venture capital. The estimates have also highlighted the role of scientific and technological environment, that can explain the delay of European countries which suffer from shortcomings in R&D spendings and, might illustrate the success of two venture capital models based on the research and development strategy: Sweden and Israel.
65

Analise de efeitos de tratamento em modelos de árvores Bayesianas / Tree-based Bayesian treatment effect analysis

Santos, Pedro Henrique Filipini dos 16 May 2019 (has links)
A inclusão do escore de propensão como uma covariável em modelos de árvores de regressão Bayesianas para inferência causal pode reduzir o viés existente nas estimações de efeitos de tratamento, o qual ocorre devido ao fenômeno de confudimento induzido por regularização. Este estudo defende o uso do escore de propensão por meio de um panorama de seleção de variáveis totalmente Bayesiano, e através do uso de Gráficos de Expectativa Individual Condicional, que se trata de um elemento que pode aprimorar a análise de efeitos de tratamento. Tal ferramental pode ser utilizado como meio de identificar grupos que possuem diferentes respostas ao tratamento aplicado e para analisar o impacto de cada variável no efeito de tratamento estimado. / The inclusion of the propensity score as a covariate in Bayesian regression trees for causal inference can reduce the bias in treatment effect estimations, which occurs due to the regularization-induced confounding phenomenon. This study advocates for the use of the propensity score by evaluating it under a full-Bayesian variable selection setting, and the use of Individual Conditional Expectation Plots as a graphical tool to improve treatment effect analysis. These tools can be used to form groups with different responses to the applied treatment, and to analyze the impact of each variable in the estimated treatment effect.
66

Stock market integration between the BRICS countries : Long-term investment opportunities / Aktiemarknadsintegration mellan BRICS länderna : Långsiktiga investeringsmöjligheter

Konradsson, Richard, Porss, Theodor January 2019 (has links)
This paper investigates the long-term diversification opportunities that exists for global investors among the BRICS nations. It analyzes how risk-averse investors can allocate funds between the countries in order to maximize the expected return in relation to the overall risk. It utilizes an empirical cointegration approach in tandem with modern portfolio theory during the time period 1999-2019. The empirical results of cointegration that is found supports the suggestion that the BRICS markets have a stable risk-premium between each other and that they all share similar systematic risk factors. The results further support the construction of a portfolio solely compromising of stocks from four out of the five BRICS markets, since then they do not share any long-run co-movements with each other. Moreover, the markets of Brazil, India, China and South Africa are strong candidates for reducing portfolio risk without sacrificing the adjusted portfolio return. The results also indicate several causal relationships between the nations, with China as the main driving force. This suggest that shocks in the Chinese market will spread and effect the rest of the BRICS markets, either directly or through one of the other markets. This is important knowledge for global policy-makers since China could be affected by markets outside the co-operation and subsequently transfer it to the rest of the BRICS markets. Since the countries accounts approximately 25 % of the global GDP, policy-makers must act with great care before implementing economic policies against China, since the consequences can have a much larger and wider effect than they anticipate.
67

The Foundations and Methods of Classical Political Science

Sebell, Dustin January 2014 (has links)
Thesis advisor: Robert C. Bartlett / This dissertation is an attempt to understand and assess the presuppositions and methods of classical political science. In the first of its two parts, the dissertation examines the meaning of the traditional view, held by authorities as far removed from one another as Cicero and Hobbes, that Socrates was the founder of political philosophy. It does so by considering the intellectual autobiography that Socrates famously delivers in Plato's Phaedo. Socrates turned to the study of pre-scientific, common-sense moral and political opinions only after he had rejected, as a very young man, both the materialist and the teleological natural science of his philosophic predecessors. It is the task of the dissertation's first part to show how the general revolution in scientific thought presented in the Phaedo, a revolution known as "the Socratic turn," laid the theoretical groundwork for classical political philosophy's characteristic focus on pre-scientific, common-sense moral distinctions. After examining "the Socratic turn," the dissertation then outlines in its second part the approach to the study of politics that Aristotle advanced on the basis of it. In particular, Aristotle's statements on the method of political science in book I of the Ethics are shown to rely on the basic insights obtained through "the turn." / Thesis (PhD) — Boston College, 2014. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Political Science.
68

O problema da liberdade na filosofia de Arthur Schopenhauer / The problem of freedom in the philosophy of Arthur Schopenhauer.

Santos, Katia Cilene da Silva 06 August 2010 (has links)
Nesta dissertação, buscamos lançar luz sobre a contradição, declarada por Schopenhauer como sendo aparente, entre a necessidade que rege a conduta humana por meio dos motivos e do caráter, e a liberdade no fenômeno, implicada na possibilidade de negação da Vontade por indivíduos singulares. Percorremos algumas obras de Schopenhauer, investigando as condições que desvendam essa contradição aparente. Assim, examinamos, por um lado, a recusa ao livre-arbítrio, e por outro, o modo como Schopenhauer explica como o indivíduo pode, através do conhecimento, subtrair-se à lei da motivação e, pela supressão da sua vontade individual, restabelecer o livre-arbítrio. / In this dissertation, we seek to shed light on the contradiction stated by Schopenhauer as apparent between the need that rules the human conduct through the motives and character, and freedom in the phenomenon, implied the possibility of denial of the will in single individuals. We have gone through some of the Schopenhauers work, investigating the conditions that reveal this apparent contradiction. Thus, we examine on the one hand, the denial of free will, and on the other hand, the way Schopenhauer explains how individuals can, through knowledge, escape the law of motivation and, through the suppression of their choice, restore free will.
69

Crédito rural e produto agropecuário municipal: uma análise de causalidade / Rural credit and agricultural output: a causality analysis

Cavalcanti, Isabel Machado 28 November 2008 (has links)
O objetivo deste trabalho é estudar a relação de causalidade entre crédito rural e produto agropecuário. Utilizando dados municipais do período 1999-2004, aplicou-se a metodologia de Granger e Huang (1997), que permite identificar o sentido da causalidade entre duas variáveis em um contexto de painel. Contrariamente à grande parte da literatura que estudou as relações de causalidade entre sistema financeiro e crescimento econômico, este trabalho não identificou a causalidade partindo da variável financeira para o produto. Em geral, os resultados apontaram causalidade unidirecional, partindo do Produto Interno Bruto da agropecuária para o crédito rural. / The main goal of this essay is to evaluate the causal relations between rural credit and agricultural output. Using municipal data for the period 1999-2004, we have implemented the Granger and Huang (1997) methodology, which allows us to identify the causality direction between two variables in a data panel context. Differently from a large part of the literature that has studied causal relations between finance and growth, this work did not find causality from the financial variable towards output. Instead, the results draw attention to unidirectional causality from agricultural output to rural credit.
70

Conscience, métacognition, inconscient : neurosciences et psychanalyse : une mise en tension dialectique / Consciousness, metacognition, unconscious : neurosciences and psychoanalysis : a dialectic exchange

Hermitte, Yann 07 January 2017 (has links)
Les neurosciences actuelles ont apporté, ces dernières décennies, des découvertes majeures sur les phénomènes d’inconscient, de la conscience et de la métacognition. En s’appuyant sur cette actualité scientifique d’une part et les connaissances accumulées depuis les premiers écrits de Freud d’autre part, il apparaît désormais possible d’entamer une articulation dialectique entre le modèle neuroscientifique et le modèle psychanalytique. Pour se faire, il convient de ne pas se contenter des définitions respectives de ces phénomènes : il faut en passer par l’analyse précise de ce sur quoi chacune des deux approches s’appuie pour les décrire.Concernant plus spécifiquement l’inconscient, quatre concepts sont inévitablement convoqués de part et d’autre : la perception, la mémoire, le temps et le langage. Néanmoins, le prolongement de la réflexion, vers la conscience et la métacognition, offre des perspectives plus larges encore : il permet d’aborder d’autres axiomes ou hypothèses comme, entre autres, l’espace de travail neuronal global, la résistance, le refoulement, l’équivoque ou l’incubation. A cela, s’ajoutent les récentes théories générales du cerveau qui, en neurosciences, supportent les questions autour de la subjectivité. Subjectivité qui, in fine, interroge sur ses dimensions conscientes et inconscientes. L’éclairage, possiblement réciproque entre neurosciences et psychanalyse, permet l’émergence de questionnements et de perspectives nouvelles. Aussi, une mise en tension dialectique de ces deux approches ouvre à l’enrichissement des connaissances sur ces phénomènes, voire à un renouvellement de ces notions fondamentales de la psychologie. / Currents neuroscience have made in recent decades, major discoveries about the unconscious, the consciousness and the metacognition. Based on this scientific news on the one hand and the knowledge accumulated since the early writings of Freud on the other hand, it now appears possible to start a dialectical link between the psychoanalytic and neuroscientific model. To do so, the respective definitions of these phenomena are insufficient: we must make an accurate analysis of the main concepts of those approaches. Concerning more specifically the unconscious, four concepts are inevitably convened on both sides: perception, memory, time and language. Nevertheless, the continuation of the reflection, toward consciousness and metacognition, offers wider prospects : it allows to address other axioms or assumptions such as, among others, the Global workspace, strength, repression, equivocation or incubation. To this are added the general theories of the brain, which approach the question of the subjectivity. But subjectivity finally asked about his conscious and unconscious aspects. Lighting, possibly reciprocal between neuroscience and psychoanalysis, allows the emergence of questions and new perspectives. Also, a dialectic exchange between both approaches open to the enrichment of knowledge about these phenomena or even a renewal of those basic concepts of psychology.

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