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Access to specialized care is essential for people with Parkinson´s disease (PD). Given the growing number of people with PD and the lack of general practitioners and neurologists, particularly in rural areas in Germany, specialized PD staff (PDS), such as PD nurse specialists and Parkinson Assistants (PASS), will play an increasingly important role in the care of people with PD over the coming years. PDS have several tasks, such as having a role as an educator or adviser for other health professionals or an advocate for people with PD to represent and justify their needs. PD nurse specialists have been established for a long time in the Netherlands, England, the USA, and Scandinavia. In contrast, in Germany, distinct PDS models and projects have been established. However, these projects and models show substantial heterogeneity in terms of access requirements, education, theoretical and practical skills, principal workplace (inpatient vs. outpatient), and reimbursement. This review provides an overview of the existing forms and regional models for PDS in Germany. PDS reimbursement concepts must be established that will foster an implementation throughout Germany. Additionally, development of professional roles in nursing and more specialized care in Germany is needed.
Access to loans and other financial services is extremely valuable for micro-, small- and medium-sized enterprises in developing and transition countries as it enables their owners as well as their employees to exploit their economic potential and to increase their income. Although this insight has lead development aid institutions to undertake many attempts to create sustainable microfinance institutions, only a small fraction of these has been successful so far. This article analyses what determines the success of attempts to provide financial services in general, and credit in particular, to low income target groups in these countries. We argue that it is crucial to understand, and to mitigate or even eliminate in practice, the serious and numerous incentive problems at the level of the lending operations as well as those at the levels of the human resource management and the governance of microfinance institutions. We attempt to show moreover, that unsolved incentive problems at only one level will ultimately undermine any potential success at the other levels. In our paper, we first analyse information and incentive problems from a theoretical perspective, using and extending the well-known Stiglitz-Weiss model of credit rationing, and derive theoretical requirements for solutions of these problems. In the light of these considerations, we then discuss how problems are solved in practice. Section 3 deals with the credit relationship. Section 4 extends the argument by showing how incentive problems within the institution can be handled, and section 5 analyses corporate governance-related problems of development finance institutions as incentive problems. In section 6 it is demonstrated why, and how, the incentive problems at the different levels, as well as their solutions, are interrelated. From this we derive the proposition that, as the institutional devices for dealing with these problems constitute a complementary system, any sustainable solution requires consistent arrangements of all elements and at all levels of the system. In the last section we will show the potential of strategic networks to set up institutions which we consider to be consistent systems for successfully solving the problems at all three levels simultaneously.
We develop a dynamic network model with heterogenous banks which undertake optimizing portfolio decisions subject to liquidity and capital constraints and trade in the interbank market whose equilibrium is governed by a tatonnement process. Due to the micro-funded structure of the decisional process as well as the iterative dynamic adjustment taking place in the market, the links in the network structures are endogenous and evolve dynamically. We use the model to assess the diffusion of systemic risk, the contribution of each bank to it as well as the evolution of the network in response to financial shocks and across different prudential policy regimes.
We develop a dynamic network model with heterogenous banks which undertake optimizing portfolio decisions subject to liquidity and capital constraints and trade in the interbank market whose equilibrium is governed by a tatonnement process. Due to the micro-funded structure of the decisional process as well as the iterative dynamic adjustment taking place in the market, the links in the network structures are endogenous and evolve dynamically. We use the model to assess the diffusion of systemic risk (measured as default probability), the contribution of each bank to it as well as the evolution of the network in response to financial shocks and across different prudential policy regimes.
The analyses of intersectoral linkages of Leontief (1941) and Hirschman (1958) provide a natural way to study the transmission of risk among interconnected banks and to measure their systemic importance. In this paper we show how classic input-output analysis can be applied to banking and how to derive six indicators that capture different aspects of systemic importance, using a simple numerical example for illustration. We also discuss the relationship with other approaches, most notably network centrality measures, both formally and by means of a simulated network.
Dynamics of chaotic strings
(2011)
The main topic of this thesis is the investigation of dynamical properties of coupled Tchebycheff map networks. At every node of the network the dynamics is given by the iteration of a Tchebycheff map, which shows strongest possible chaotic behaviour. By applying a coupling between the various individual dynamics along the links of the network, a rich structure of complex dynamical patterns emerges. Accordingly, coupled chaotic map networks provide prototypical models for studying the interplay between local dynamics, network structure, and the emergent global dynamics. An exciting application of coupled Tchebycheff map lattices in quantum field theory has been proposed Beck in Spatio-temporal chaos and vacuum fluctuations of quantized fields' (2002). In this so-called chaotic string model, the coupled map lattice dynamics generates the noise needed for the Parisi-Wu approach of stochastic quantization. The remarkable obversation is that the respective dynamics seems to reproduce distinguished numerical values of coupling constants that coincide with those observed in the standard model of particle physic. The results of this thesis give insights into the chaotic string model and its network generalization from a dynamical point of view. This leads to a deeper understanding of the dynamics, which is essential for a critical discussion of possible physical embeddings. Apart from this specific application to particle physics, the investigated concepts like synchronization or a most random behaviour of the dynamics are of general interest for dynamical system theory and the science of complex networks. As a first approach, discrete symmetry transformations of the model are studied. These transformations are formulated in a general way in order to be also applicable to similar dynamics on bipartite network structures. An observable of main interest in the chaotic string model is the interaction energy. In Spatio-temporal chaos and vacuum fluctuations of quantized fields' (2002) it has been observed that certain chaotic string couplings, corresponding to a vanishing interaction energy, coincide with coupling constants of the standard model of elementary particle physics. Since the interaction energy is basically a spatial correlation measure, an interpretation of the respective dynamical states in terms of a most random behaviour is tempting. In order to distinguish certain states as most random', or evoke another dynamical principle, a deeper understanding of the dynamics essential. In the present thesis the dynamics is studied numerically via Lyapunov measures, spatial correlations, and ergodic properties. It is shown that the zeros of the interaction energy are distinguished only with respect to this specific observable, but not by a more general dynamical principle. The original chaotic string model is defined on a one-dimensional lattice (ring-network) as the underlying network topology. This thesis studies a modification of the model based on the introduction of tunable disorder. The effects of inhomogeneous coupling weights as well as small-world perturbations of the ring-network structure on the interaction energy are discussed. Synchronization properties of the chaotic string model and its network generalization are studied in later chapters of this thesis. The analysis is based on the master stability formalism, which relates the stability of the synchronized state to the spectral properties of the network. Apart from complete synchronization, where the dynamics at all nodes of the network coincide, also two-cluster synchronization on bipartite networks is studied. For both types of synchronization it is shown that depending on the type of coupling the synchronized dynamics can display chaotic as well as periodic or quasi-periodic behaviour. The semi-analytical calculations reveal that the respective synchronized states are often stable for a wide range of coupling values even for the ring-network, although the respective basins of attraction may inhabit only a small fraction of the phase space. To provide analytical results in closed form, for complete synchronization the stability of all fixed points and period-2 orbits of all chaotic string networks are determined analytically. The master stability formalism allows to treat the ring-network of the chaotic string model as a special case, but the results are valid for coupled Tchebycheff maps on arbitrary networks. For two-cluster synchronization on bipartite networks, selected fixed points and period-2 orbits are analyzed.
The paper is a follow-up to an article published in Technique Financière et Developpement in 2000 (see the appendix to the hardcopy version), which portrayed the first results of a new strategy in the field of development finance implemented in South-East Europe. This strategy consists in creating microfinance banks as greenfield investments, that is, of building up new banks which specialise in providing credit and other financial services to micro and small enterprises, instead of transforming existing credit-granting NGOs into formal banks, which had been the dominant approach in the 1990s. The present paper shows that this strategy has, in the course of the last five years, led to the emergence of a network of microfinance banks operating in several parts of the world. After discussing why financial sector development is a crucial determinant of general social and economic development and contrasting the new strategy to former approaches in the area of development finance, the paper provides information about the shareholder composition and the investment portfolio of what is at present the world's largest and most successful network of microfinance banks. This network is a good example of a well-functioning "private public partnership". The paper then provides performance figures and discusses why the creation of such a network seems to be a particularly promising approach to the creation of financially self-sustaining financial institutions with a clear developmental objective.
The paper is a follow-up to an article published in Technique Financière et Developpement in 2000 (see the appendix to the hardcopy version), which portrayed the first results of a new strategy in the field of development finance implemented in South-East Europe. This strategy consists in creating microfinance banks as greenfield investments, that is, of building up new banks which specialise in providing credit and other financial services to micro and small enterprises, instead of transforming existing credit-granting NGOs into formal banks, which had been the dominant approach in the 1990s. The present paper shows that this strategy has, in the course of the last five years, led to the emergence of a network of microfinance banks operating in several parts of the world. After discussing why financial sector development is a crucial determinant of general social and economic development and contrasting the new strategy to former approaches in the area of development finance, the paper provides information about the shareholder composition and the investment portfolio of what is at present the world's largest and most successful network of microfinance banks. This network is a good example of a well-functioning "private public partnership". The paper then provides performance figures and discusses why the creation of such a network seems to be a particularly promising approach to the creation of financially self-sustaining financial institutions with a clear developmental objective.
Während sich die Entwicklungsfinanzierung in Theorie und Praxis generell mit dem Finanzwesen in Entwicklungs- und Transformationsländern befasst, steht im Teilgebiet der Microfinance die Frage im Vordergrund, wie in diesen Ländern der Zugang ärmerer Bevölkerungsgruppen und speziell von Klein- und Kleinstunternehmer(innen), Kleinbauern und sonstigen wirtschaftlich Selbständigen aus eher niedrigen sozialen Schichten zu Kredit und anderen Finanzdiensleistungen verbessert werden kann. Obwohl es einige Vorläufer gibt, die schon früh die allgemeine Politik der Entwicklungsländer bezüglich ihrer Finanzsektoren und ebenso die dazu passende Entwicklungshilfe-Politik der Industrieländer der 60er und 70er Jahre mit ökonomisch-theoretischen Argumenten scharf kritisiert haben,1 waren in der Vergangenheit weder Entwicklungsfinanzierung im allgemeinen noch Microfinance im besonderen ein wirklich ernst genommener Gegenstand der ökonomischen Literatur, die man zum mainstream rechnen kann. Dem entspricht es, dass sich auch die Praxis der Entwicklungsfinanzierung sehr lange weitgehend unabhängig von ökonomisch- theoretischen Überlegungen vollzogen hat. Diese Situation hat sich seit mehr als einem Jahrzehnt grundlegend verändert. Dies hat einen wesentlichen Grund darin, dass sich in der entwicklungspolitischen Praxis auf dem Gebiet der Finanzierung von Klein- und Kleinstbetrieben, eben Microfinance, Erfolge erzielen ließen, die vorher unvorstellbar waren. Mit einer deutlichen commercial orientation und einer Ausrichtung auf die genuinen Probleme des financial institution building konnte erreicht werden, dass es inzwischen einige Dutzend Finanzinstitutionen in Entwicklungs- und Transformationsländern gibt, die ökonomisch stabil und sogar profitabel sind und mit ihrem Leistungsangebot eine große Anzahl von "armen" Kunden erreichen, die bei den Kreditabteilungen der herkömmlichen Banken kaum über die Schwelle gelassen würden.2 Dies hat die Aufmerksamkeit von Forschern aus dem mainstream erweckt. Mindestens ebenso wichtig sind aber die immanenten Entwicklungen innerhalb der ökonomischen Theorie. Mit ihrer Hinwendung zum institutionalistischen Denkansatz hat die Wirtschaftstheorie auf einmal eine neue Aufmerksamkeit für die Phänomene entwickelt, die für die Praktiker der Entwicklungsfinanzierung seit langem von zentraler Bedeutung sind: Inzwischen kann man theoretisch nachweisen, dass es in der Tat Zugangsprobleme zu Kredit für "kleine Leute" gibt, dass das Angebot von Kredit für sie beschränkt ist und dass es nicht genügt, einfach nur staatlich auferlegte Restriktionen – die so genannte financial repression – zu beseitigen, um ....