A network experiment in continuous time: The influence of link costs

In recent work on non-cooperative network formation star-shaped networks play an important role. In a particular theoretical model of Bala and Goyal (2000) center-sponsored stars are the only strict Nash networks. In testing this theoretical model, Falk and Kosfeld (2003) do not find experimental evidence that players select the center-sponsored star. Based on a slight modification of Bala and Goyal’s model, we design a network formation experiment in which, depending on link costs, periphery-sponsored stars and the empty network are the only strict Nash networks. We observe that almost all groups not only reach a strict Nash network once but also switch the center player in periphery-sponsored stars several times. The main innovation in our experiment is to use a continuous time framework which we believe to be a more realistic setting to study behavior in network formation situations and which makes coordination on stars much easier than simultaneous strategy adaptation in discrete time. Electronic Supplementary Material Supplementary material is available in the online version of this article at http://dx.doi.org/10.1007/s10683-006-9125-1. JEL Classification C72 · C92 · D81     

Post Bretton Woods deviations from purchasing power parity in G7 exchange rates—an empirical exploration

Exchange rates have deviated substantially and idiosyncratically from purchasing power parity (PPP) since the breakdown of Bretton Woods. In this paper, a model incorporating both traditional PPP and financial market variables is constructed and tested on the US dollar's six G7 exchange rates during the floating rate era. Empirical tests show that the model's common set of variables—with consistent signs—can explain the divergent behavior of G7 exchange rates during 1973.2–90.2. Idiosyncracies are reflected in different subsets of the model's variables entering significantly into each exchange rate's regression; the existence of stable relationships is demonstrated by the equations' co-integration.     

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Tax reform: Chasing the elusive dream

The paper provides a bird's-eye view of the long and arduous task of reforming the federal individual income tax. As a starting point for reviewing the major reforms, the authors evaluate Secretary Simon's criteria that underlie his contention that the tax system was badly in need of a thorough overhaul. Principles that should guide tax reforms are spelled out. Conflicts that arise with the application of these principles are highlighted. An examination of reform efforts in light of the principles and criteria set in the Treasury Department's Blue Prints for Tax Reform forms the basis for evaluating reforms enacted over the period 1978–2001. The review suggests that we are partway towards achieving the tax man's dream of equity, efficiency, and simplicity.The task of comprehensive reform is monumental in its dimension and far reaching in itspotential impact on our economic well-being.[William E. Simon, 1977, p. 11]     

Evolution of networks—an experimental analysis

It is the main aim of our paper to study network formation in experimental setups in discrete and continuous time. Our design is inspired by the theoretical model on network formation by Bala and Goyal (Econometrica, 68(5): 1181–1229, 2000) as well as the experiments by Callander and Plott (J. Public Econ., 89: 1469–1495, 2005) and Falk and Kosfeld (IEW Working Paper, University of Zürich, Zürich, Switzerland, No. 146, 2003). In particular, we analyze the role of star-shaped networks which are strict Nash-equilibria of the corresponding network formation game. Our experimental results show that strict Nash networks prove to be a good indicator for predicting network formation, particularly in continuous time. In explaining our results, it turns out that, among others, the complexity in coordinating on stars, the inequity aversion against unequal payoff distribution in the network, and the groups’ degrees of activity are the most important determinants for the formation of strict Nash networks.      

Information dissemination on intellectual capital in mergers and acquisitions: purchase price allocations,press releases and business press

In order to reduce information asymmetries in relation to a firm's current decisions and long-term strategy, firms must consistently provide information to stakeholders. This paper investigates intellectual capital (IC) information disclosed in mergers and acquisitions (M&A) provided through three different disclosure channels (voluntary press releases, related newspaper articles and subsequent mandatory corporate disclosures in the notes to the financial statements). For a sample of 215 randomly selected US and European M&As, we analyse 215 press releases, 1025 newspaper articles and 215 purchase price allocations. Our findings suggest that IC disclosure in press releases is not perceived as informative and qualitative forward-looking IC information in voluntary corporate disclosures appears to lack credibility. Moreover, we empirically demonstrate interdependencies across the three disclosure channels. The business press seems to filter IC information provided in press releases. The amount of IC disclosure in the notes to the financial statements is positively associated with prior IC disclosure in newspaper articles, but negatively associated with IC disclosure in press releases. The managements of acquirer firms appear to pay attention to news coverage and public opinion. However, both voluntary and mandatory corporate disclosures appear to substitute rather than complement each other.     

Débridement mit topischer Therapie kombinieren

Bew?hrte und neue Therapieans?tze zur Behandlung chronischer Wunden – Unter chronischen, schlecht heilenden Wunden leiden in Deutschland etwa 800.000 Menschen. Weil die Erkrankung für den Patienten schwerwiegende Einschr?nkungen im Alltag mit sich bringt, steht eine effektive Wundbehandlung im Zentrum des Interesses.     

Messung und Klassifikation destechnischen Fortschritts Eine Antwort an A. Heertje

Ohne ZusammenfassungA. Heertje: Zur Ottschen Klassifikation des technischen Fortschritts. In dieser Zeitschrift, S. 227 f.     

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