The surrounding of a vertex in a network can be more or less symmetric. We derive measures of a specific kind of symmetry of a vertex which we call degree symmetry--the property that many paths going out from a vertex have overlapping degree sequences. These measures are evaluated on artificial and real networks. Specifically we consider vertices in the human metabolic network. We also measure ...

In this work, we explore the relations between sales growth and a set of innovation indicators that capture the different sources, modes and results of the innovative activity undertaken within firms. We exploit a rich panel on innovation activity of Spanish manufacturing firms, reporting detailed CIS-type information continuously over the period 2004-2011. Standard GMMpanel estimates of the av...

OBJECTIVES. Responsiveness has been identified as one of the intrinsic goals of health care systems. Little is known, however, about its determinants. Our objective is to investigate the potential country-level drivers of health system responsiveness. DATA SOURCE. Data on responsiveness are taken from the World Health Survey. Information on country-level characteristics is obtained from a varie...

We show that, for any rotationally symmetric projection with a single virtual viewpoint, it is possible to design a two-mirror rotationally symmetric system that realizes the projection exactly. These mirror pairs are derived from two coupled differential equations. We give examples in which the projections from the sphere at infinity are stereographic, perspective, and equiresolution.

The authors conducted a meta-analysis of the relationship between turnover rates and organizational performance to (a) determine the magnitude of the relationship; (b) test organization-, context-, and methods-related moderators of the relationship; and (c) suggest future directions for the turnover literature on the basis of the findings. The results from 300 total correlations (N = 309,245) a...

PURPOSE To investigate the dynamics of volunteering in the population aged 50 years or older across 11 Continental European countries. DESIGN AND METHODS Using longitudinal data from the first 2 waves of the Survey of Health, Ageing and Retirement in Europe, we run multivariate regressions on a set of binary-dependent variables indicating transitions from active volunteering to inactivity and...

Let Γ = G1 ∗G2 ∗ ... ∗Gn ∗ ... be a free product of at least two but at most countably many cyclic groups. With each such group Γ we associate a family of C*-algebras, denoted C∗ r (Γ,PΛ) and generated by the reduced group C*-algebra C∗ r Γ and a collection PΛ of projections onto the `2-spaces over certain subsets of Γ. We determine W ∗(Γ,PΛ), the weak closure of C∗ r (Γ,PΛ) in L(`2(Γ)), and us...

We examine the internal geometry of a Kleinian surface group and its relations to the asymptotic geometry of its ends, using the combinatorial structure of the complex of curves on the surface. Our main results give necessary conditions for the Kleinian group to have ‘bounded geometry’ (lower bounds on injectivity radius) in terms of a sequence of coefficients (subsurface projections) computed ...

We describe a method for discretizing C continuous surface(s) in R immersed in a non-conforming tetrahedralization. The method consists of constructing a homeomorphic mapping from the tetrahedrons in a background mesh to ones conforming to the immersed geometry. Such a map relies on the way we parametrize the surface(s) of the immersed geometry over a collection of a nearby triangular faces wit...

The main goal of the court system is to differentiatebetween those who obeyed the law and those who did not. We describe a mechanism design framework that facilitates the characterization of a set of procedural mechanisms that would minimize the resources used to achieve this goal. This framework can also help to formulate and evaluate procedural rules, and to identify necessary and sufficient ...