1,720,987 research outputs found
Numerical solution of dynamic equilibrium models under Poisson uncertainty
No full textWe propose a simple and powerful numerical algorithm to compute the transition process in continuous-time dynamic equilibrium models with rare events. In this paper we transform the dynamic system of stochastic differential equations into a system of functional differential equations of the retarded type. We apply the Waveform Relaxation algorithm, i.e., we provide a guess of the policy function and solve the resulting system of (deterministic) ordinary differential equations by standard techniques. For parametric restrictions, analytical solutions to the stochastic growth model and a novel solution to Lucas' endogenous growth model under Poisson uncertainty are used to compute the exact numerical error. We show how (potential) catastrophic events such as rare natural disasters substantially affect the economic decisions of households. (C) 2013 Elsevier B.V. All rights reserved
Am Anfang war der Fluch, und der Fluch war das Öl: Ein erneuter Blick auf die Ökonomie des Rohstoff-Fluchs
No full textThe seminal papers of Sachs and Warner (1995, 2001) put forward as a stylized fact that “economies with abundant natural resources have tended to grow less rapidly than natural-resource-scarce economies” and gave a rise to what is known as “The Resource Curse”. More empirical evidence has then followed showing that point resources, espicially oil, have weakened countries' development courses particularly in Africa, Middle East and Latin America. This dissertation revisits key questions of the oil resource curse literature in four studies. The main aim is to shed the light on the underlying conditioning context, when evaluating the final impact of natural resource abundance on a country's political stability, tax revenues and economic activity. In particular, it shows that the existence of sizable shadow economies can mitigate the effect of negative oil price shocks on political instability and tax mobilization efforts. It also stresses on the importance of within-country disaggregation of resource boom effects among oil-producing sub-nationals and their neighbors. Finally, it reconsiders the role of oil rents in prolonging autocratic regime survival after taking into account the type of posed mass threat, the dictator's time horizon (short run vs. long run) and the size of oil wealth.Die bahnbrechenden Arbeiten von Sachs und Warner (1995, 2001) stellten als stilisierte Tatsache fest, dass "Volkswirtschaften mit reichlich natürlichen Ressourcen dazu neigen, weniger schnell zu wachsen als rohstoffarme Volkswirtschaften", und gaben Anlass zu dem, was als "Ressourcenfluch" bekannt ist. Es folgten weitere empirische Belege, die zeigen, dass Ressourcen, insbesondere Erdöl, den Entwicklungskurs von Ländern, insbesondere in Afrika, dem Nahen Osten und Lateinamerika, beeinträchtigen. In dieser Dissertation werden die Schlüsselfragen der Literatur über den Fluch der Ölressourcen in vier Studien aufgegriffen. Das Hauptziel besteht darin, den zugrunde liegenden Kontext zu beleuchten, wenn es darum geht, die endgültigen Auswirkungen des Reichtums an natürlichen Ressourcen auf die politische Stabilität, die Steuereinnahmen und die Wirtschaftstätigkeit eines Landes zu bewerten. Insbesondere wird gezeigt, dass das Vorhandensein umfangreicher Schattenwirtschaften die Auswirkungen negativer Ölpreisschocks auf die politische Instabilität und die Bemühungen um die Mobilisierung von Steuern abschwächen kann. Ferner wird betont, wie wichtig es ist, die Auswirkungen des Ressourcenbooms innerhalb eines Landes zwischen den ölproduzierenden Ländern und ihren Nachbarn aufzuschlüsseln. Schließlich wird die Rolle der Öleinkünfte bei der Verlängerung des Überlebens autokratischer Regime unter Berücksichtigung der Art der Massenbedrohung, des Zeithorizonts des Diktators (kurzfristig vs. langfristig) und des Umfangs des Ölreichtums erneut untersucht
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Fiskalpolitik in Allgemeinen Gleichgewichtsmodellen
No full textDas erste Kapitel meiner Dissertation hinterfragt den konventionellen keynesianischen
Standpunkt, dass antizyklische Fiskalpolitik reale Variablen über den Konjunkturzyklus
stabilisiert. Ich präsentiere empirische Ergebnisse eines strukturellen
VECM Modells die zeigen, dass Staatsschulden in den Vereinigten Staaten prozyklisch
mit dem Produktionsniveau verlaufen. Dieses Ergebnis mag wenig überraschend
sein, wenn man Korrelationen betrachtet, allerdings zeigt die Analyse einen kausalen
Zusammenhang auf. Anschließend modelliere ich Fiskalpolitik als Regeln, die durch
endogene Modellvariablen beeinflusst werden. Die Koeffizienten dieser Regeln werden
so kalibriert, dass sie mit dem prozyklischen Verhalten der Staatsschulden übereinstimmen.
Das Ergebnis ist, dass die Standardabweichung wichtiger makroökonomischer
Variablen deutlich niedriger ist, verglichen mit Regeln kalibriert auf antizyklischer
Staatsverschuldung. Der Grund ist ein Vermögenseffekt, der in diesem Modell
aufgrund der „perpetual-youth“ Struktur der Agenten entsteht. Daher hält die Ricardianische
Äquivalenz nicht mehr und Veränderungen der Staatsschulden haben
einen Effekt auf das Vermögen der Haushalte und, folgerichtig, auf ihre Konsum-
Freizeit Entscheidung. Dieser Vermögenskanal war insbesondere in der Great Recession
bedeutend. Meine Analyse zeigt einen neuen Weg für fiskalpolitische Entscheidungsträger
auf, Vermögenseffekte zu erzeugen und zwar dadurch, das Staatsschulden
als automatischer Stabilisator wirken.
Das zweite Kapitel der Dissertation beschäftigt sich mit den Interaktionen von
Geld- und Fiskalpolitik. Eine empirische Analyse zeigt, dass die Politik der FED
von dem gegenwärtigen Stand der Fiskalpolitik beeinflusst wird. Zunächst schätze
ich die Parameter einer Taylor-Zinsregel. Der Schwerpunkt der empirischen Analyse
ist allerdings die Schätzung zweier Markov-switching Modelle mit zeitvariablen Übergangswahrscheinlichkeiten.
Die Analyse zeigt, dass die Interaktion zwischen Geld und Fiskalpolitik sich über die Zeit verändert und zwischen unterstützenden und nicht-unterstützenden Regimen wechselt.
Kapitel drei, ein gemeinsames Projekt mit Olaf Posch von der Universität Hamburg
und Santanu Chatterjee von der University of Georgia, beschäftigt sich mit den
Wachstumseffekten von Verzögerungen in der Umsetzung von staatlichen Investitionsprojekten.
Staatsausgaben, die den öffentlichen Kapitalstock erhöhen werden als
überlegen zu puren staatlichen Konsumausgaben angesehen, da sie Effekte entlang
der Angebotsseite erzeugen. Während entwickelte Länder diese Ausgaben nutzen um
die negativen Effekte von Rezession abzumildern und um ihr Wachstum zu stärken,
nutzen Entwicklungsländer diese Ausgaben um die Voraussetzungen für Wachstum
zu schaffen. Staatliche Investitionsprojekte sind insbesondere durch lange Umsetzungsverzögerungen gekennzeichnet durch die erforderliche Planung, Ausschreibung, Vertrags- und Bauphase.In the first of the three chapters of my dissertation I challenge the conventional
Keynesian view that countercyclical fiscal policy stabilizes real variables over
the business cycle. I present empirical evidence that government debt moves procyclical
with output in the United States using a structural vector error correction
model.
Then, I model fiscal policy via fiscal rules with feedback to endogenous variables.
Calibrating those rules with coefficients in line with procyclical debt gives us sizably
lower standard deviations compared to a model with coefficients that would generate
countercyclical debt. The reason for this finding is a wealth channel that emerges
in my model because of the introduction of a perpetual-youth structure. Hence, the
Ricardian equivalence is broken and movements in debt affect household’s wealth
and, therefore, the consumption-leisure decision. This wealth channel proofed to be
particularly important in the Great Recession and my analysis suggests a new way
governments can generate wealth effects, by using government debt as an automatic
stabilizer.
The striking and provocative consequence is that classical (countercyclical) Keynesian fiscal policy destabilizes the business cycle in this basic framework. Remarkably, this
channel plays a role for the propagation of all shocks that affect output and, hence,
is important even in the absence of exogenous fiscal policy innovations.
The second chapter addresses the interactions between monetary and fiscal policy.
Empirically, I show that the FED’s policy is affected by the stance of fiscal
policy. I do so by estimating a state-of-the art Taylor-type interest rate rule. Then,
I estimate Markov-switching models allowing for time-varying transition probabilities
showing that those interactions vary over time between accommodative and
non-accommodative regimes. Along the theoretical dimension, I use a cheap talk
game between central bank and government to microfound policy interactions and
regime switches. Exogenous (or, potentially, endogenous) changes in the expectation
of agents trigger policy shifts. For example, if a Ricardian government increase government
spending this might trigger the expectation that the government becomes
Non-Ricardian. Since debt matters for the conduct of monetary policy, the central
bank reacts by changing its responsiveness to debt in the Taylor rule. Put differently,
changes in the prior beliefs within this game, the pendant to the estimated Markovswitching
probabilities, can trigger different outcomes and, hence, different weights
in the Taylor-rule. This will have effects on the transmission of shocks and, hence,
on the quantitative and qualitative results.
Chapter three, joint work with Olaf Posch from the University of Hamburg and
Santanu Chatterjee from the University of Georgia, discusses the (growth) effects of
implementation delays in the accumulation of the public capital stock. Government
expenditures into public capital is considered superior to wasteful government consumption
expenditures as they trigger supply-side effects. While developed countries
use government investment expenditures to counter adverse effects of Recessions and
to foster growth, developing countries use investment into public capital to remove
the bottlenecks for economic growth. Public infrastructure programs, in particular,
are subject to large implementation delays (or lags) due to the required planning, bidding,
contracting, and construction process. We add to the literature on fiscal policy
in endogenous growth models by building a stochastic endogenous growth model in
continuous time with public capital. In this model, implementation lags generate
uncertainty in the public capital accumulation process: the government continuously
spends but the completion of the public investment project is unknown. We provide a
numerical solution calibrated on the U.S. economy. We find that the implementation
lags in the accumulation of public capital have sizable effects on agents’ behavior.
Then, we evaluate the effects of three policy reforms
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Unvollständige Informationen in dynamischen stochastischen allgemeinen Gleichgewichtsmodellen
No full textIn dieser Dissertation konzentriere ich mich auf Modelle mit unvollständige Informationen im Sinne von partiellen und heterogenen Informationen. Modelle mit heterogenen Informationen erzeugen Erwartungen höherer Ordnung, die zu dem so genannten Problem endloser Rekursion führen
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Essays on the Interdependencies and Linkages between the Real Economy and Financial Markets - Interactions of Monetary and Fiscal Policy and Asset Prices in General Equilibrium Models
No full textDispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
