On Mitra's Sufficient Condition for Topological Chaos: Seventeen Years Later
Liuchun Deng, M. Ali Khan
Economics Letters,
March
2018
Abstract
This letter reports an easy extension of Mitra’s “easily verifiable” sufficient condition for topological chaos in unimodal maps, and offers its application to reduced-form representations of two economic models that have figured prominently in the recent literature in economic dynamics: the check- and the M-map pertaining to the 2-sector Robinson–Solow–Srinivasan (RSS) and Matsuyama models respectively. A consideration of the iterates of these maps establishes the complementarity of the useful 2001 condition with the 1982 (LMPY) theorem of Li–Misiurewicz–Pianigiani–Yorke when supplemented by a geometric construction elaborated in Khan–Piazza (2011).
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On Growing through Cycles: Matsuyama's M-map and Li-Yorke Chaos
Liuchun Deng, M. Ali Khan
Journal of Mathematical Economics,
January
2018
Abstract
Recent work of Gardini et al. (2008), building on earlier work of Mitra (2001) and Mukherji (2005), considers the so-called M-map that generates a dynamical system underlying Matsuyama’s (1999) endogenous growth model. We offer proofs of the fact that there do not exist 3- or 5-period cycles in the M-map, and an example (a numerical proof) of the existence of a 7-period cycle. We use the latter, and a construction in Khan and Piazza (2011), to identify a range of parameter values of the M-map that guarantee the existence of cycles of all periods, except 3 and 5. Our argumentation relies on, and reports, the first four iterations of the M-map that may have independent interest.
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Big Fish in Small Banking Ponds? Cost Advantages and Foreign Affiliate Presences
Michael Koetter, Rients Galema
Journal of International Money and Finance,
2018
Abstract
We distinguish cost advantage at home from cost advantage vis-à-vis incumbent banks in destination markets to explain the probability of foreign bank affiliate lending. We combine detailed affiliate lending data of all German banks with public bank micro data from 59 destination markets. The likelihood to operate foreign affiliates depends positively on both types of cost advantage. Only cost advantage at home is economically significant. Generally, risk, return, and unobservable bank traits explain a larger share of the variation in foreign affiliate operations. Less profitable, more risky, and larger banks are more likely to operate affiliates abroad.
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Mikroökonometrische Evaluation und das Selektionsproblem – Ein anwendungsorientierter Überblick über nichtparametrische Lösungsverfahren
Eva Reinowski
Zeitschrift für Evaluation 2,
Nr. 2,
2006
Abstract
Die Anwendung von Evaluationsverfahren zur Beurteilung unterschiedlicher Handlungsalternativen gewinnt in verschiedenen Forschungsfeldern zunehmend an Bedeutung. Von den zur Lösung des dabei auftretenden Selektionsproblems entwickelten Verfahren haben insbesondere die nichtparametrischen große Bedeutung in der empirischen Anwendung erlangt. In diesem Beitrag wird ein Überblick über diese Verfahren gegeben, wobei die bisher bestehende Lücke zwischen einführenden Texten und der weiterführenden, eher formalen Literatur geschlossen werden soll. Dazu werden die Vor- und Nachteile der Verfahren, die nötigen Annahmen sowie die Anforderungen an die Datenbasis erläutert. Aus der Darstellung wird ersichtlich, dass für die empirische Anwendung keine Methode zur Lösung des Selektionsproblems den anderen generell überlegen ist. Alle Ansätze beruhen auf bestimmten Grundannahmen, und jeder Schätzer ist verzerrt, wenn die zur Verfügung stehende Datenbasis nicht zu diesen Annahmen passt.
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Matching kleiner Stichproben. Ein Vergleich verschiedener Verfahren
Eva Dettmann
Südwestdeutscher Verlag fuer Hochschulschriften. Saarbrücken,
2009
Abstract
Die Anwendung moderner Evaluationsverfahren ist aus der wissenschaftlichen Politikberatung nicht mehr wegzudenken. Unabhängig davon ist die Idee dieser Methoden auf viele Gebiete der Ökonomie und der Sozialwissenschaften übertragbar. Da die konkrete Fragestellung ebenso wie die verfügbaren Informationen die Eignung eines Verfahrens für den praktischen Einsatz beeinflusst, fällt die Auswahl der “richtigen“ Methode oft schwer. Die Studie ist als Beitrag zur Entwicklung von Richtlinien für den praktischen Einsatz speziell von Matchingverfahren zu sehen, dessen Ziel darin besteht, die diskutierten Methoden einem breiten Anwenderkreis zugänglich zu machen. Charakteristisch dabei ist ein enger Bezug zur praktischen Anwendung, der auch die Rahmenbedingungen für die durchgeführte Simulation vorgibt. Die Ergebnisse zeigen, dass es sich lohnt, bei der Wahl eines Matchingansatzes „über den Tellerrand zu schauen“ und bisher nur in anderen Wissenschaftsbereichen genutzte Verfahren eventuell anzupassen und für die Bildung von Vergleichsgruppen nutzbar zu machen. Dies gilt insbesondere für die Wahl eines geeigneten Distanzmaßes.
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Microeconometric Evaluation of Selected ESF-funded ALMP-Programmes
Eva Reinowski, Birgit Schultz
IWH Discussion Papers,
Nr. 17,
2006
Abstract
The study evaluates different ESF-funded labour market programmes by comparing the labour market status at different points in time after the treatment. In order to solve the selection problem we employ a standard matching algorithm with a multi-dimensional distance measure. The effects of the analyzed programmes (wage subsidies, start-up subsidies and qualification measures for recipients of social welfare) are very heterogeneous. It can be observed that the direct integration into the regular labour market provides an advantage for the supported individuals. Its lasting effects, however, strongly depend on the group of persons being supported, the type of treatment and the employers’ financial share.
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Distance Functions for Matching in Small Samples
Eva Dettmann, Christian Schmeißer, Claudia Becker
Computational Statistics & Data Analysis,
Nr. 5,
2011
Abstract
The development of ‘standards’ for the application of matching algorithms in empirical evaluation studies is still an outstanding goal. The first step of the matching procedure is the choice of an appropriate distance function. In empirical evaluation situations often the sample sizes are small. Moreover, they consist of variables with different scale levels which have to be considered explicitly in the matching process. A simulation is performed which is directed towards these empirical challenges and supplements former studies in this respect. The choice of the analysed distance functions is determined by the results of former theoretical studies and recommendations in the empirical literature. Thus, two balancing scores (the propensity score and the index score) and the Mahalanobis distance are considered. Additionally, aggregated statistical distance functions not yet used for empirical evaluation are included. The matching outcomes are compared using non-parametric scale-specific tests for identical distributions of the characteristics in the treatment and the control groups. The simulation results show that, in small samples, aggregated statistical distance functions are the better choice for summarising similarities in differently scaled variables compared to the commonly used measures.
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Subsidized Vocational Training: Stepping Stone or Trap? – Assessing Empirical Effects using Matching Techniques
Eva Dettmann, Jutta Günther
Swiss Journal of Economics and Statistics,
Nr. 4,
2013
Abstract
Using replacement matching on the basis of a statistical distance function we try to answer the question of whether subsidized vocational training is related to a negative image effect for the graduates. The results show that young people with equal qualifications acquired during subsidized vocational training are disadvantaged solely due to the kind of education they have received. The probability of finding adequate employment is lower than in the control group. Besides the 'general effect' of support we also find less favorable job opportunities for those who attended 'external' as compared to 'workplace-related' training.
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Intellectual Property Rights Policy, Competition and Innovation
Daron Acemoglu, Ufuk Akcigit
Journal of the European Economic Association,
Nr. 1,
2012
Abstract
To what extent and in what form should the intellectual property rights (IPR) of innovators be protected? Should a company with a large technology lead over its rivals receive the same IPR protection as a company with a more limited advantage? In this paper, we develop a dynamic framework for the study of the interactions between IPR and competition, in particular to understand the impact of such policies on future incentives. The economy consists of many industries and firms engaged in cumulative (step-by-step) innovation. IPR policy regulates whether followers in an industry can copy the technology of the leader. We prove the existence of a steady-state equilibrium and characterize some of its properties. We then quantitatively investigate the implications of different types of IPR policy on the equilibrium growth rate and welfare. The most important result from this exercise is that full patent protection is not optimal; instead, optimal policy involves state-dependent IPR protection, providing greater protection to technology leaders that are further ahead than those that are close to their followers. This is because of a trickle-down effect: providing greater protection to firms that are further ahead of their followers than a certain threshold increases the R&D incentives also for all technology leaders that are less advanced than this threshold.
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The Schumpeterian Growth Paradigm
Philippe Aghion, Ufuk Akcigit, Peter Howitt
Annual Review of Economics,
2015
Abstract
In this review, we argue that the Schumpeterian growth paradigm, which models growth as resulting from innovations involving creative destruction, sheds light on several aspects of the growth process that cannot be properly addressed by alternative theories. We focus on three important aspects for which Schumpeterian growth theory delivers predictions that distinguish it from other growth models, namely, (a) the role of competition and market structure, (b) firm dynamics, and (c) the relationship between growth and development.
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