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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.
111

Johannese perspektiewe oor inklusiwiteit en eksklusiwiteit van verlossing / Johannine perspectives on inclusivity and exclusivity of salvation

Rousseau, Pieter Abraham 06 1900 (has links)
Die Johannese geskrifte (Evangelie en Briewe) word veralgemenend binne die Christendom gelees en die uniekheidsbeklemtoninge ten opsigte van Jesus as enige Verlosser word ook so verstaan. Hierdie hoofsaaklik sosiaal-wetenskaplike ondersoek was gefokus op Johannes se aansprake ten opsigte van Jesus en is gedoen om bewus te maak van die sosiaal-kulturele onderbou van die geskrifte. As sodanig is dit bedoe! om heuristies in te werk ten einde bestaande hermeneuse beter te dien sodat die boodskap van die Nuwe Testament effektiewer oorgedra kan word. Dit is ook gepoog om bevindinge uit die studie deur te trek na die gesekulariseerde samelewing en pluralistiese religieuse standpunt wat te Iande bestaan. Die teksgedeeltes wat eksegeties ondersoek is, bevat die aspekte van aanvaarding of verwerping van Jesus as die unieke Godsagent wat ewige /ewe meedeel. Dit het geblyk dat die begrip in Johannes nie net op oneindigheid in die hiemamaals dui nie, maar veral op kwaliteit in die hede. Johannes se postulaat is dat Jesus konstant hierdie lewe meedeel aan hulle wat in Hom glo. Die vraag na relevansie van 'n religie uit Judaistiese oorsprong in 'n AfroWesterse samelewing en kultuur is vanuit die aspekte van kulturele relatiwisme en relatiwiteit hanteer. Dit word aanvaar dat die ingrype van God deur Jesus Christus binne die Israelitiese volksmilieu en Mediterreense kultuur plaasgevind het, maar dat dit wat Johannes aan sy lesers herbevestig het, vir aile mense relevant is. Jesus is die unieke Godsagent wat ewige lewe meedeel, wat, as sodanig, nie menslike sterflikheid negeer nie, maar dit transendeer. / The social-scientific research for this treatise concentrated on John's assertion of Jesus' uniqueness. The selected Scripture portions for exegesis contain the aspects of receiving or rejecting Him as God's Agent who bestows eternal life. Eternal lifo in John does not so much denote never ending life, but rather excellent quality of life in the present. The relevancy of a religion from a Judaistic origin in an Afro-Western cultural society was treated on the aspects of cultural relativism and cultural relativity. The conclusion accedes to the fact that God's interaction with man in the person of Jesus Christ took place within an Israelite national milieu and Mediterranean culture, but what John reasserted is relevant for all time- the life that Jesus bestows does not negate mortality, but transcends it. / New Testament / M. Th. (Nuwe Testament)
112

A Christian perspective on enabling spiritual formation in relation to work

Howard, Susan January 2017 (has links)
This thesis is an action research investigation into the influence of my Christian habitus on my consultancy practice. My research question: How does my Christian faith inform the work I do? is located within the academic field of Spirit at Work. The complexity and difficulties of my professional practice are explored using the literature on Christian spirituality. My investigation uses the research method of practical theology to explore: my own Christian perspective; my role as a spiritual mentor; the nature of spiritual formation; and, faith in relation to work. The analytical methods of theological reflection, narrative inquiry, and autoethnography support the critical reflection. Five themes emerge: the evangelical basis of my Christian perspective; an understanding of the grace of God; the consideration of resistance as sin; strategies to enable spiritual formation; and complex combinations of faith in relation to work. This study has enabled me to interrogate my approach to spiritual formation in relation to work. My inquiry in a variety of contexts – with colleagues, one individual, and with a client –has developed my ability as a reflexive practitioner, and has strengthened my vocation as a spiritual mentor. I have used the Holistic Development Model (HDM) to underpin my approach to spiritual mentoring, and created a Christian interpretation of it. Spiritual formation is explored through the topics of: church, faith, purpose and mission using scripture, adventure and leadership, and difficulty and struggle. The research provides insights into my work as a professional consultant in the area of leadership development. My reflexive learning, combined with participative inquiry, provides an insider perspective on living within an evangelical Christian worldview. Difficulties over how to interpret Christian faith in work contexts are explored, particularly with regard to inclusivity. The research links spiritual formation with leadership, concluding that, in my practice, faith takes precedence.
113

Distribuição elementar e de radionuclídeos na produção e uso de fertilizantes fosfotados no Brasil

SAUEIA, CATIA H.R. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:52:02Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:56Z (GMT). No. of bitstreams: 0 / O fertilizante é considerado um componente essencial para a agricultura, pois sua utilização aumenta e repõe os nutrientes naturais do solo, perdidos por desgaste ou erosão. No processo de obtenção dos fertilizantes fosfatados, o concentrado de rocha reage com ácido sulfúrico concentrado produzindo ácido fosfórico e sulfato de cálcio (fosfogesso), como subproduto. O ácido fosfórico é utilizado para a produção do superfosfato triplo (TSP), superfosfato simples (SSP), monoamônio fosfato (MAP) e diamônio fosfato (DAP). A rocha fosfatada usada como matéria prima apresenta em sua composição radionuclídeos das séries naturais do urânio e tório. Durante o ataque químico do concentrado de rocha, as espécies presentes na reação, estáveis e radioativas, são redistribuídas entre o ácido fosfórico (matéria prima dos fertilizantes), e o fosfogesso, de acordo com sua solubilidade e características químicas. Enquanto os fertilizantes são comercializados, o fosfogesso fica estocado em pilhas podendo impactar o meio ambiente. Com a finalidade de entender a distribuição dos elementos e dos radionuclídeos no processo industrial de produção de fertilizantes fosfatados, foram analisadas amostras de concentrado de rocha, de fertilizantes (SSP, TSP, MAP e DAP) e fosfogesso de três procedências nacionais denominadas indústrias A, B e C. A técnica utilizada para a análise elementar foi a análise por ativação com nêutrons, que permitiu analisar os elementos Ba, Co, Cr, Fe, Hf, Na, Sc, Ta, Th, U, Zn e Zr, e as terras raras, La, Ce, Nd, Sm, Eu, Tb, Yb e Lu. Os resultados obtidos permitiram concluir que em geral, as terras raras se distribuem de forma homogênea em todos os fertilizantes e no fosfogesso, exceto o Lu. Os fertilizantes SSP e TSP apresentaram concentrações de todos os elementos analisados da mesma ordem de grandeza da rocha de origem. O mesmo comportamento foi observado nos fertilizantes MAP e DAP, exceto para os elementos Co, Sc e U. Os elementos pertencentes à série radioativa natural do urânio (238U, 234U, 230Th, 226Ra e 210Pb), do tório (232Th, 228Ra e 228Th) e o K-40, foram determinados por meio da espectrometria gama e alfa. As amostras de fertilizantes MAP e DAP, que são diretamente derivadas do ácido fosfórico, apresentaram baixa concentração para o 226Ra, 228Ra e 210Pb, enquanto que para o U e Th as concentrações encontradas foram da mesma ordem de grandeza da rocha de origem. Os fertilizantes SSP e TSP, que são obtidos pela mistura de ácido fosfórico com concentrado de rocha, apresentaram concentrações mais elevadas para os radionuclídeos das séries naturais. Avaliou-se a exposição devido a sucessivas aplicações de fertilizantes e fosfogesso, calculando-se a dose interna devida à aplicação por 10, 50 e 100 anos. Os valores encontrados estão abaixo do limite de 2,4 mSv a-1, mostrando que esta prática é negligenciável. / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
114

La théologie du salut selon le cycle hebdomadaire syro-antiochien : Étude historique et théologique / The theology of salvation according to the Syro-Antiochian weekly cycle : An historical and theological study.

Habil, Menzer 11 January 2014 (has links)
Le cycle hebdomadaire syro-antiochien est un cycle liturgique férial, simple et non eucharistique. Le livre de prières dont on sert pendant ces jours fériaux est appelé en syriaque Shehimo, ce que signifie « simple » ou « banal ». La valeur théologique des offices du Shehimo réside dans leur fonction actualisante qui transforme les événements salvifiques du passé en réalité vécue constamment par les fidèles à travers la mémoire. L’étude du livre, de sa structure liturgique, de son contenu et de ses sources révèle la grande richesse du cycle hebdomadaire qui a su assimiler plusieurs textes bibliques, apocryphes, patristiques et historiques afin de les présenter aux fidèles d’une manière simple pour les accompagner dans leur voyage hebdomadaire entre le premier et le huitième jour de la semaine. D’autre part, l’économie du salut réalisée par le Verbe de Dieu constitue la base solide sur laquelle se fondent les textes du Shehimo. Dieu a crée l’homme motivé par son amour et lorsque l’homme est tombé dans le péché, Dieu l’a sauvé par le même amour divin invraisemblable. L’incarnation du Fils, sa vie, son enseignement, ses miracles, sa crucifixion, sa mort et sa résurrection visaient toujours le salut de l’homme. D’une manière poétique, imaginative et mélodique, le chrétien se souvient de toute cette œuvre salvifique et divine que le Christ a réalisée en sa faveur, il affirme son attachement à cette œuvre, il chante la gloire de son Sauveur et il exprime ardemment son désir d’être digne de lui chanter éternellement sa gloire dans son Royaume céleste. / The Syro-Antiochian weekly cycle is an ordinary, simple and non-eucharistic liturgical cycle. The prayer book which we use during the ordinary days, is called Shehimo in Syriac, which means “simple” or “trivial”. The theological value of the services of the Shehimo lies in their actualizing function which transforms the salvational events of the past into a reality that is constantly lived by the faithful through their memory. The study of the book, of its liturgical structure, its content and its sources, reveals the great richness of the weekly cycle which was able to assimilate many biblical, apocryphal, patristic and historical texts in order to present them to the faithful in a simple manner so as to accompany them in their weekly journey from the first to the eighth day of the week. On the other hand, the economy of salvation that was realized by the Word of God constitutes the solid base on which the texts of the Shehimo are founded. When God created man He was motivated by His love; when man fell in sin, God has saved him with the same inconceivable divine love. The incarnation of the Son, His life, His teachings, His miracles, His crucifixion, His death and His resurrection always aimed at the salvation of man. In a poetic, imaginative and melodic way, the Christian believer remembers all this salvational and divine work that Christ has accomplished for his sake, and thus the Christian believer affirms his attachment to this work. He chants the glory of his Savior and expresses passionately his desire to be worthy of eternally chanting to Him His glory in His heavenly kingdom.
115

Minimizing Overhead for Fault Tolerance in Event Stream Processing Systems

Martin, André 20 September 2016 (has links) (PDF)
Event Stream Processing (ESP) is a well-established approach for low-latency data processing enabling users to quickly react to relevant situations in soft real-time. In order to cope with the sheer amount of data being generated each day and to cope with fluctuating workloads originating from data sources such as Twitter and Facebook, such systems must be highly scalable and elastic. Hence, ESP systems are typically long running applications deployed on several hundreds of nodes in either dedicated data-centers or cloud environments such as Amazon EC2. In such environments, nodes are likely to fail due to software aging, process or hardware errors whereas the unbounded stream of data asks for continuous processing. In order to cope with node failures, several fault tolerance approaches have been proposed in literature. Active replication and rollback recovery-based on checkpointing and in-memory logging (upstream backup) are two commonly used approaches in order to cope with such failures in the context of ESP systems. However, these approaches suffer either from a high resource footprint, low throughput or unresponsiveness due to long recovery times. Moreover, in order to recover applications in a precise manner using exactly once semantics, the use of deterministic execution is required which adds another layer of complexity and overhead. The goal of this thesis is to lower the overhead for fault tolerance in ESP systems. We first present StreamMine3G, our ESP system we built entirely from scratch in order to study and evaluate novel approaches for fault tolerance and elasticity. We then present an approach to reduce the overhead of deterministic execution by using a weak, epoch-based rather than strict ordering scheme for commutative and tumbling windowed operators that allows applications to recover precisely using active or passive replication. Since most applications are running in cloud environments nowadays, we furthermore propose an approach to increase the system availability by efficiently utilizing spare but paid resources for fault tolerance. Finally, in order to free users from the burden of choosing the correct fault tolerance scheme for their applications that guarantees the desired recovery time while still saving resources, we present a controller-based approach that adapts fault tolerance at runtime. We furthermore showcase the applicability of our StreamMine3G approach using real world applications and examples.
116

Wie wirken Unternehmensberichte auf den Aktienkurs? - Eine statistische Untersuchung mittels Event Coincidence Analysis und Superposed Epoch Analysis

Rimatzki, Florian 14 November 2016 (has links) (PDF)
Several times a year companies publish business reports to openly account for their business activities. This thesis examines the effect of those business reports on stock prices of businesses in the German automotive industry. Different statistical methods such as Event Coincidence Analysis and Superposed Epoch Analysis are used to examine possible negative and positive reactions of stock prices before and after the disclosure of business reports. It shows that there seems to be a stronger influence of a negative business report on the daily abnormal rate of return than of a positive business report. Furthermore the thesis confirms the hypothesis of Roeder that the information from a business report is processed not only on the day of publication but also on the day after.
117

L'impact des changements climatiques sur l'application de l'article 234 de la Convention des Nations Unies sur le droit de la mer de 1982

Renaud-Moyneur, Sarah 08 1900 (has links)
L’Arctique est victime de bouleversements majeurs en raison des changements climatiques. Contrairement au régime général pour la zone économique exclusive, l'article 234 de la Convention des Nations unies sur le droit de la mer de 1982 autorise les États côtiers à adopter et à imposer des standards nationaux (plutôt qu'internationaux) pour prévenir et maîtriser la pollution du milieu marin par les navires mais seulement dans les zones de leur zone économique exclusive recouvertes par les glaces « pendant la majeure partie de l'année ». Or, les données et rapports scientifiques prévoient qu'en raison du réchauffement climatique exacerbé dans la région, l'océan Arctique sera libre de glace pendant plusieurs mois chaque année, et ce, à compter de 2050. Une telle transformation physique semblerait remettre en cause l'applicabilité de l'article 234 et les droits qui en découlent pour les États côtiers. Le mémoire propose donc d'aborder cet enjeu en analysant le contexte et les motivations des États au moment où l'article 234 a été adopté. Une attention particulière sera portée à l’étude du développement du droit de la mer moderne ainsi qu’aux négociations entourant l’article 234, en vue de formuler des arguments en faveur de son applicabilité future, basés sur les méthodes d’interprétation des traités. / The Arctic region is the victim of major upheavals due to climate change. Unlike the general regime for the exclusive economic zone, Article 234 of the 1982 United Nations Convention on the Law of the Sea allows coastal states to adopt and impose national (rather than international) standards to prevent and control the pollution of the marine environment by ships, but only in areas of their exclusive economic zone covered by ice "for most of the year". However, the data and scientific reports predict that due to exacerbated global warming in the region, the Arctic Ocean will be free of ice for several months each year, starting in 2050. Such a physical transformation would seem to call into question the applicability of Article 234 and the resulting rights of coastal States. This thesis therefore proposes to address this issue by analyzing the context and the motivations of the States at the time when Article 234 was adopted. Particular attention will be paid to the study of the development of the modern law of the sea as well as to the negotiations around Article 234, in order to formulate arguments in favor of its future applicability, based on treaty interpretation methods.
118

Flexible Regression for Different Types of Multivariate Functional Data

Volkmann, Alexander 14 October 2024 (has links)
In dieser Dissertation werden neue Regressionsansätze für multivariate longitudinale oder funktionale Daten entwickelt, die eine flexible Modellierung von interessierenden Kovariableneffekten ermöglichen. Die Abhängigkeit innerhalb und zwischen den verschiedenen Zielgrößen wird über latente multivariate Gauss-Prozesse modelliert. Die Regressionsansätze folgen einem zweistufigen Verfahren, in dem in einem vorgelagerten Schritt multivariate funktionale Hauptkomponentenanalysen eingesetzt werden, um sparsame empirische Basen für die Gauss-Prozesse zu konstruieren. Drei verschiedene Regressionsmodelle werden für verschiedene Arten multivariater longitudinaler oder funktionaler Daten entwickelt. Das erste Projekt führt das zweistufige Verfahren für multivariate normalverteilte funktionale Daten ein, die eine gekreutzte oder genestete Datenstruktur aufweisen können. Das Regressionsmodell ist im frequentistischen Rahmenmodell der funktionalen additiven gemischten Modelle eingebettet und wird durch Anwendungen auf Bewegungsdaten und Sprachdaten illustriert. Das zweite Projekt entwickelt ein bayesianisches Regressionsgerüst für multilevel multivariate funktionale Daten, die verschiedenen punktweisen Verteilungen folgen. Das erlaubt es, verschiedene Datentypen, wie etwa binäre, Zähl- oder kontinuierliche funktionale Daten gleichzeitig zu modellieren, was durch eine Anwendung auf Berliner Verkehrsdaten veranschaulicht wird. Das dritte Projekt vereint multivariate longitudinale normalverteilte Daten mit einer Ereigniszeit-Zielgröße in einem gemeinsamen bayesianischen Modellierungsansatz. Solche Modelle werden oft im medizinischen Bereich verwendet, beispielsweise wenn der Fokus der Analyse auf der Schätzung der Assoziation zwischen longitudinalen Messungen von Biomarkern und dem Überleben von Patienten mit chronischen Lebererkrankung liegt. / In this thesis, novel regression approaches for multivariate longitudinal or functional data are developed, which allow to flexibly model the covariate effects of interest. The dependency within and between the different outcomes is modeled using latent multivariate Gaussian processes. The regression approaches adopt a two-step procedure where, in a preliminary step, multivariate functional principal component analyses are employed to generate parsimonious empirical bases for the Gaussian processes. Three different regression models are developed for different types of longitudinal or multivariate functional data. The first project establishes the two-step procedure for multivariate Gaussian functional data which can exhibit a crossed or nested multilevel structure. The regression model is embedded in the frequentist functional additive mixed model framework and is demonstrated by applications in movement data and speech production data. The second project develops a Bayesian regression framework for multilevel multivariate functional data that follow different pointwise distributions. This allows to simultaneously model data of different types such as binary, count, or continuous functional data, which is illustrated by an application to Berlin traffic data. The third project combines multivariate longitudinal Gaussian data with a time-to-event outcome in a Bayesian joint modelling approach. Such models are often used in medical contexts where the main point of interest lies in estimating the association between longitudinal measurements of biomarkers and e.g. the survival of patients as in the presented application to a chronic liver disease. All projects are accompanied by simulation studies to assess the estimation accuracy and the models' limitations.
119

Quantile regression in risk calibration

Chao, Shih-Kang 05 June 2015 (has links)
Die Quantilsregression untersucht die Quantilfunktion QY |X (τ ), sodass ∀τ ∈ (0, 1), FY |X [QY |X (τ )] = τ erfu ̈llt ist, wobei FY |X die bedingte Verteilungsfunktion von Y gegeben X ist. Die Quantilsregression ermo ̈glicht eine genauere Betrachtung der bedingten Verteilung u ̈ber die bedingten Momente hinaus. Diese Technik ist in vielerlei Hinsicht nu ̈tzlich: beispielsweise fu ̈r das Risikomaß Value-at-Risk (VaR), welches nach dem Basler Akkord (2011) von allen Banken angegeben werden muss, fu ̈r ”Quantil treatment-effects” und die ”bedingte stochastische Dominanz (CSD)”, welches wirtschaftliche Konzepte zur Messung der Effektivit ̈at einer Regierungspoli- tik oder einer medizinischen Behandlung sind. Die Entwicklung eines Verfahrens zur Quantilsregression stellt jedoch eine gro ̈ßere Herausforderung dar, als die Regression zur Mitte. Allgemeine Regressionsprobleme und M-Scha ̈tzer erfordern einen versierten Umgang und es muss sich mit nicht- glatten Verlustfunktionen besch ̈aftigt werden. Kapitel 2 behandelt den Einsatz der Quantilsregression im empirischen Risikomanagement w ̈ahrend einer Finanzkrise. Kapitel 3 und 4 befassen sich mit dem Problem der h ̈oheren Dimensionalit ̈at und nichtparametrischen Techniken der Quantilsregression. / Quantile regression studies the conditional quantile function QY|X(τ) on X at level τ which satisfies FY |X QY |X (τ ) = τ , where FY |X is the conditional CDF of Y given X, ∀τ ∈ (0,1). Quantile regression allows for a closer inspection of the conditional distribution beyond the conditional moments. This technique is par- ticularly useful in, for example, the Value-at-Risk (VaR) which the Basel accords (2011) require all banks to report, or the ”quantile treatment effect” and ”condi- tional stochastic dominance (CSD)” which are economic concepts in measuring the effectiveness of a government policy or a medical treatment. Given its value of applicability, to develop the technique of quantile regression is, however, more challenging than mean regression. It is necessary to be adept with general regression problems and M-estimators; additionally one needs to deal with non-smooth loss functions. In this dissertation, chapter 2 is devoted to empirical risk management during financial crises using quantile regression. Chapter 3 and 4 address the issue of high-dimensionality and the nonparametric technique of quantile regression.
120

Testing for causality with Wald tests under nonregular conditions

Burda, Maike M. 04 December 2001 (has links)
Das Kausalitaetskonzept von Granger und die Impuls-Antwort-Analyse sind zwei Konzepte, die haeufig verwendet werden, um kausale Beziehungen zwischen zwei Variablen in vektorautoregressiven (VAR) Modellen zu untersuchen. Wenn das VAR Modell mehr als zwei Variablen umfasst, besteht eine Erweiterung des Standard Granger Kausalitaetskonzepts darin, Kausalitaet an hoeheren Prognosehorizonten zu messen. Die Kausalitaetsbeziehungen unter diesem erweiterten Granger Kausalitaetskonzept werden mit denen bei Standard Granger Kausalitaet (Ein-Schritt-Prognose) und mit Kausalitaet im Sinne der Impuls-Antwort-Analyse verglichen. Es wird insbesondere dargestellt, inwiefern das erweiterte Granger Kausalitaetskonzept als Verallgemeinerung der letztgenannten Konzepte aufgefasst werden kann. Wenn Kausalitaet an Prognosehorizonten groesser als eins gemessen wird und das VAR Modell mehr als zwei Variablen umfasst, impliziert die Nullhypothese, dass eine Variable nicht kausal fuer eine andere Variable sei, nichtlineare Restriktionen auf die VAR Koeffizienten. (In nichtstationaeren VAR Modellen treten nichtlineare Restriktionen sogar schon unter dem Standard Granger Kausalitaetskonzept auf.) Aufgrund der speziellen Form der Restriktionen kann es vorkommen, dass die Standard Wald Statistik nicht mehr die uebliche, asymptotische Chiquadrat-Verteilung hat. Dieses Problem wird im allgemeinen in der Praxis ignoriert. Beispiel 4.1, Proposition 4.1 und Korollar 4.1 zeigen jedoch, dass dieses Problem nicht irrelevant ist. Zwei Loesungen werden in Proposition 5.1 und Proposition 5.2 in Form eines randomisierten Wald Tests sowie eines Wald Tests mit verallgemeinerter Inverse angeboten. In einer anschliessenden kleinen Simulationsstudie werden Groesse und Macht dieser modifizierten Wald Tests relativ zu der des Standard Wald Tests untersucht fuer verschiedene stationaere trivariate VAR(1)-Modelle. In einem kurzen Ueberblick werden zudem Vor- und Nachteile alternativer Testverfahren (Bootstrap, sequentielle Tests) zusammengefasst. / The concepts of standard Granger causality and impulse response analysis are often used to investigate causal relationships between variables in vector autoregressive (VAR) models. In VAR models with more than two variables, the concept of standard Granger causality can be extended by studying prediction improvement at forecast horizons greater than one. The causal relationships which arise under this extended Granger causality concept are compared to those arising under the standard Granger causality concept (one-step forecasts) and those arising with impulse-response-analysis. In particular, it is illustrated inhowfar the extended Granger causality concept can be understood as a generalization of the standard Granger causality concept and even of impulse-response-analysis. If causality is measured at forecast horizons greater than one, and if there are more than two variables in the VAR system, the null hypothesis that one variable is not causal for another variable implies restrictions which are a nonlinear function of the VAR coefficients. (In nonstationary VAR models, nonlinear restrictions already arise under the standard Granger causality concept.) Due to the special form of the restrictions, the standard Wald test may no longer have the usual asymptotic chisquare-distribution under the null hypothesis. This problem is commonly neglected in practice. However, Example 4.1, Corollary 4.1 and Proposition 4.1 of this thesis illustrate that this problem is not irrelevant. Furthermore, Propositions 5.1 and 5.2 show that this problem may be overcome, at least in stationary VAR models, by using either a randomized Wald test or a Wald test with generalized inverse. Size and Power of these modified Wald tests relative to the standard Wald test are investigated in a small simulation study for different stationary, trivariate VAR(1) models. Moreover, the pros and cons of alternative testing strategies (bootstrap, sequential tests) are summarized in a brief overview.

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