Winner-relaxing and winner-enhancing Kohonen maps: Maximal mutual information from enhancing the winner

The magnification behaviour of a generalized family of self-organizing feature maps, the Winner Relaxing and Winner Enhancing Kohonen algorithms is analyzed by the magnification law in the one-dimensional case, which can be obtained analytically. The Winner-Enhancing case allows to acheive a magnification exponent of one and therefore provides optimal mapping in the sense of information theory. A numerical verification of the magnification law is included, and the ordering behaviour is analyzed. Compared to the original Self-Organizing Map and some other approaches, the generalized Winner Enforcing Algorithm requires minimal extra computations per learning step and is conveniently easy to implement.Comment: 6 pages, 5 figures. For an extended version refer to cond-mat/0208414 (Neural Computation 17, 996-1009

The Politics of Institutional Learning and Creation: Bank Crises and Supervision in East Central Europe

This article examines the political conditions shaping the creation of new institutional capabilities. It analyzes bank sector reforms in the 1990s in three leading postcommunist democracies – Hungary, Poland, and the Czech Republic. It shows how different political approaches to economic transformation can facilitate or hinder the ability of relevant public and private actors to experiment and learn their new roles. With its emphasis on insulating power and rapidly implementing self-enforcing economic incentives, the “depoliticization” approach creates few changes in bank behavior and, indeed impedes investment in new capabilities at the bank and supervisory levels. The “deliberative restructuring” approach fostered innovative, costeffective monitoring structures for recapitalization, a strong supervisory system, and a stable, expanding banking sector.http://deepblue.lib.umich.edu/bitstream/2027.42/40112/3/wp726.pd

Winner-Relaxing Self-Organizing Maps

A new family of self-organizing maps, the Winner-Relaxing Kohonen Algorithm, is introduced as a generalization of a variant given by Kohonen in 1991. The magnification behaviour is calculated analytically. For the original variant a magnification exponent of 4/7 is derived; the generalized version allows to steer the magnification in the wide range from exponent 1/2 to 1 in the one-dimensional case, thus provides optimal mapping in the sense of information theory. The Winner Relaxing Algorithm requires minimal extra computations per learning step and is conveniently easy to implement.Comment: 14 pages (6 figs included). To appear in Neural Computatio

Firms, Courts, and Reputation Mechanisms: Towards a Positive Theory of Private Ordering

This Essay formulates a positive model that predicts when commercial parties will employ private ordering to enforce their agreements. The typical enforcement mechanism associated with private ordering is the reputation mechanism, in which a merchant community punishes parties in breach of contract by denying them future business. The growing private ordering literature argues that these private enforcement mechanisms can be superior to the traditional, less efficient enforcement measures provided by public courts. However, previous comparisons between public and private contractual enforcement have presented a misleading dichotomy by failing to consider a third enforcement mechanim: the vertically integrated firm. This Essay develops a model that comprehensively addresses three distinct types of enforcement mechanisms--firms, courts, and reputation-based private ordering. The model rests on a synthesis of transaction cost economics, which compares the efficiencies of firms versus markets, and the private ordering literature, which compares the efficiencies of public courts versus private ordering. It hypothesizes that private ordering will arise when agreements present enforcement difficulties, high-powered market incentives are important, and the costs of entry barriers are low. The Essay then conducts an illustrative test by comparing the model\u27s predictions to documented instances of private ordering

Using Artificial Intelligence in Wireless Sensor Routing Protocols

This paper represents a dissertation about how an artificial intelligence technique can be applied to wireless sensor networks. Due to the constraints on data processing and power consumption, the use of artificial intelligence has been historically discarded in these kind of networks. However, in some special scenarios the features of neural networks are appropriate to develop complex tasks such as path discovery. In this paper, we explore the performance of two very well known routing paradigms, directed diffusion and Energy-Aware Routing, and our routing algorithm, named SIR, which has the novelty of being based on the introduction of neural networks in every sensor node. Extensive simulations over our wireless sensor network simulator, OLIMPO, have been carried out to study the efficiency of the introduction of neural networks. A comparison of the results obtained with every routing protocol is analyzed

The Politics of Institutional Learning and Creation: Bank Crises and Supervision in East Central Europe

This article examines the political conditions shaping the creation of new institutional capabilities. It analyzes bank sector reforms in the 1990s in three leading postcommunist democracies – Hungary, Poland, and the Czech Republic. It shows how different political approaches to economic transformation can facilitate or hinder the ability of relevant public and private actors to experiment and learn their new roles. With its emphasis on insulating power and rapidly implementing self-enforcing economic incentives, the “depoliticization” approach creates few changes in bank behavior and, indeed impedes investment in new capabilities at the bank and supervisory levels. The “deliberative restructuring” approach fostered innovative, costeffective monitoring structures for recapitalization, a strong supervisory system, and a stable, expanding banking sector.Institutional change, transition economies, bank crises, bank supervision, learn

Why explicit performance bonds are absent from employment contracts

Contains bibliographical references (p. 19-20)