Purely infinite crossed products by endomorphisms

We study the crossed product $C^*$-algebra associated to injective endomorphisms, which turns out to be equivalent to study the crossed product by the dilated autormorphism. We prove that the dilation of the Bernoulli $p$-shift endomorphism is topologically free. As a consequence, we have a way to twist any endomorphism of a \D-absorbing $C^*$-algebra into one whose dilated automorphism is essentially free and have the same $K$-theory map than the original one. This allows us to construct purely infinite crossed products $C^*$-algebras with diverse ideal structures.Comment: Corrected misprints. Clarified some points in Section 3. Added a reference. Re-submitted to JMA

An analysis of the impact of implementing Revenue Management Systems on hotel operational performance

The aim of this paper was to analyse the degree to which hotels whose managers employ a Revenue Management System (RMS) as a strategy to increase demand outperform other non-RMS-user establishments. This analysis was based on the assumption that increased demand due to us-ing an RMS will either increase a hotel's room occupancy (RO) or increase its achieved room rate (ARR), and eventually increase its revenue per available room (RevPAR), efficiency rate (ER) and average labour produc-tivity. The study used a sample of 106 chain hotels with a rating of three or more stars located in Andalusia (Spain). The econometric estimations show that the effectiveness of an RMS as a tool for improving perform-ance was generally achieved in these hotels through better management of occupancy, especially in the low season

Power and the economics of organizations

I discuss the main theories on the role of power in organizations, emphasizing two questions: how should power be divided among employees? and: what mechanisms should the organization choose to ensure that those with power use it efficiently

On the Informativeness of the DNA Promoter Sequences Domain Theory

The DNA promoter sequences domain theory and database have become popular for testing systems that integrate empirical and analytical learning. This note reports a simple change and reinterpretation of the domain theory in terms of M-of-N concepts, involving no learning, that results in an accuracy of 93.4% on the 106 items of the database. Moreover, an exhaustive search of the space of M-of-N domain theory interpretations indicates that the expected accuracy of a randomly chosen interpretation is 76.5%, and that a maximum accuracy of 97.2% is achieved in 12 cases. This demonstrates the informativeness of the domain theory, without the complications of understanding the interactions between various learning algorithms and the theory. In addition, our results help characterize the difficulty of learning using the DNA promoters theory.Comment: See http://www.jair.org/ for any accompanying file