Characterization of hyperbolicity and generalized shadowing lemma

J. Mather characterized uniform hyperbolicity of a discrete dynamical system as equivalent to invertibility of an operator on the set of all sequences bounded in norm in the tangent bundle of an orbit. We develop a similar characterization of nonuniform hyperbolicity and show that it is equivalent to invertibility of the same operator on a larger, Fr\'echet space. We apply it to obtain a condition for a diffeomorphism on the boundary of the set of Anosov diffeomorphisms to be nonuniformly hyperbolic. Finally we generalise the Shadowing lemma in the same context

Assessing the Effect of Visualizations on Bayesian Reasoning through Crowdsourcing

People have difficulty understanding statistical information and are unaware of their wrong judgments, particularly in Bayesian reasoning. Psychology studies suggest that the way Bayesian problems are represented can impact comprehension, but few visual designs have been evaluated and only populations with a specific background have been involved. In this study, a textual and six visual representations for three classic problems were compared using a diverse subject pool through crowdsourcing. Visualizations included area-proportional Euler diagrams, glyph representations, and hybrid diagrams combining both. Our study failed to replicate previous findings in that subjects' accuracy was remarkably lower and visualizations exhibited no measurable benefit. A second experiment confirmed that simply adding a visualization to a textual Bayesian problem is of little help, even when the text refers to the visualization, but suggests that visualizations are more effective when the text is given without numerical values. We discuss our findings and the need for more such experiments to be carried out on heterogeneous populations of non-experts

Improving the Service Quality as a Socially Responsible Activity of Hotel Companies

In this article, the results of the survey examining quality of service in spa hotels are interpreted. Research was conducted in five spas in West Morava region during August and September 2008. Service quality was measured with a model based on SERVQUAL model. Collected data were analyzed using statistical methods of descriptive statistical analysis and analysis of variables ANOVA, which were useful in defining whether there is statistically significant connection between dependant variables (questions on expectations and perception) and independent variables (structure of respondents regarding their occupation). The results indicate negative SERVQUAL gap in total (-0.21). The largest negative SERVQUAL gap was noted at the first determinant related to the tangible elements of service, which further points to conclusion that main problems in providing high-quality services in the spa hotels are inappropriate arrangement of facilities and equipment, time worn of facilities in general, lack of understanding of contemporary demand trends, unaccomplished process of hotel privatization, uniformity of tourism offer and lack of market research related to hotel services consumers. In the authors’ opinion, the aforementioned problems could be overcome with creation and implementation of development strategies with short and long term development plans, as well as with investment incentives in spa tourism development. The organization with strategy based on the principles of social responsibility has the potential to built and sustain successful relationships with present and potential customers, as well as with all interested stakeholders.service quality, SERVQUAL, spa hotels, corporate social responsibility

Periodic approximation of exceptional Lyapunov exponents for semi-invertible operator cocycles

We prove that for semi-invertible and H\"older continuous linear cocycles $A$ acting on an arbitrary Banach space and defined over a base space that satisfies the Anosov Closing Property, all exceptional Lyapunov exponents of $A$ with respect to an ergodic invariant measure for base dynamics can be approximated with Lyapunov exponents of $A$ with respect to ergodic measures supported on periodic orbits. Our result is applicable to a wide class of infinite-dimensional dynamical systems.Comment: Revised version following the suggestions of referees. Accepted for publication in Annales Academiae Scientiarum Fennica

Almost sure invariance principle for random piecewise expanding maps

We prove a fiberwise almost sure invariance principle for random piecewise expanding transformations in one and higher dimensions using recent developments on martingale techniques

The study of social space - ethnoarchaeological perspective

El espacio social es un concepto ambiguo cuyo componente “material” está determinado por el carácter del componente “social”, puesto que la organización de los objetos en el espacio y el espacio mismo, responden a las normas sociales del comportamiento humano. Por lo tanto, planteamos estudiar la organización y la producción del espacio social de una sociedad cazadora-recolectora concreta – la sociedad yámana - a través del análisis de las actividades cotidianas que figuran en las fuentes etnográficas. El trabajo interdisciplinario desde un enfoque etnoarqueológico nos ayudará a descubrir cuáles son las posibilidades de reconocer arqueológicamente esta regularidad y a resolver algunas preguntas acerca del estudio de la organización social en prehistoria

Private Valuation of a Public Good in Three Auction Mechanisms.

We evaluate the impact of three auction mechanisms – the Becker–DeGroot–Marschak (BDM) mechanism, the second-price auction (SPA), and the random nth-price auction (NPA) – in the measurement of private willingness-to-pay and willingness-to-accept for a pure public good. Our results show that the endowment effect is lower with the BDM mechanism. In this market mechanism, the effect disappears after a few repetitions. Yet, on a logarithmic scale, the random nth-price auction yields the highest speed of convergence towards equality of welfare indices. We also observe that subjects value public goods in reference to their private subjective benefit derived from their public good funding.auction mechanisms; WTP-WTA disparity; private provisions; public goods;