'Core' values safe at BGS

In answer to Culshaw and Lee’s criticism of BGS policy (Geoscientist 21.10 p11), we invite readers to review our fouryear strategy (links on website) which is unchanged since publication in spring 2009. It highlights the change from ‘systematic’ to ‘responsive’ survey. BGS will complete this by the end of the strategy period, while at the same time ensuring that the 2D UK survey is refreshed and, where necessary, newly surveyed. The strategy also introduces a strong focus on remapping the UK shelf

Actualizing Organizational Core Values: Putting Theory into Practice

The literature on organizational culture and leading by shared values suggests a prescriptive model for use by leaders in actualizing stated organizational core values. Utilizing a qualitative case study approach, this study sought to examine the efficacy of this theoretical model in representing actual efforts by practitioners to embed diversity as a new organizational core value. Leadership actions to embed and actualize diversity as an institutional core value at two private universities were examined and compared. Findings suggest the theoretical model inadequately addresses the critical role of contextual assessment and under represents the dynamic cyclical nature of value embedding and actualization processes, particularly with respect organizations with high stakeholder turnover such as institutions of higher education

Polarization of the fermionic vacuum by a global monopole with finite core

We study the vacuum polarization effects associated with a massive fermionic field in a spacetime produced by a global monopole considering a nontrivial inner structure for it. In the general case of the spherically symmetric static core with finite support we evaluate the vacuum expectation values of the energy-momentum tensor and the fermionic condensate in the region outside the core. These quantities are presented as the sum of point-like global monopole and core-induced contributions. The asymptotic behavior of the core-induced vacuum densities are investigated at large distances from the core, near the core and for small values of the solid angle corresponding to strong gravitational fields. As an application of general results the flower-pot model for the monopole's core is considered and the expectation values inside the core are evaluated.Comment: 22 pages, 4 figure

Vacuum polarization by a global monopole with finite core

We investigate the effects of a $(D+1)$-dimensional global monopole core on the behavior of a quantum massive scalar field with general curvature coupling parameter. In the general case of the spherically symmetric static core, formulae are derived for the Wightman function, for the vacuum expectation values of the field square and the energy-momentum tensor in the exterior region. These expectation values are presented as the sum of point-like global monopole part and the core induced one. The asymptotic behavior of the core induced vacuum densities is investigated at large distances from the core, near the core and for small values of the solid angle corresponding to strong gravitational fields. In particular, in the latter case we show that the behavior of the vacuum densities is drastically different for minimally and non-minimally coupled fields. As an application of general results the flower-pot model for the monopole's core is considered and the expectation values inside the core are evaluated.Comment: 22 pages, 4 figures, misprint is corrected, discussion is added, figures are change

Core-stable Rings in Auctions with Independent Private Values

We propose a semi-cooperative game theoretic approach to check whether a given coalition is stable in a Bayesian game with independent private values. The ex ante expected utilities of coalitions, at an incentive compatible (noncooperative) coalitional equilibrium, describe a (cooperative) partition form game. A coalition is core-stable if the core of a suitable characteristic function, derived from the partition form game, is not empty. As an application, we study collusion in auctions in which the bidders’ final utility possibly depends on the winner’s identity. We show that such direct externalities offer a possible explanation for cartels’ structures (not) observed in practice.auctions, Bayesian game, collusion, core, partition function game

Core-stable rings in auctions with independent private values.

We propose a semi-cooperative game theoretic approach to check whether a given coalition is stable in a Bayesian game with independent private values. The ex ante expected utilities of coalitions, at an incentive compatible (noncooperative) coalitional equilibrium, describe a (cooperative) partition form game. A coalition is core-stable if the core of a suitable characteristic function, derived from the partition form game, is not empty. As an application, we study collusion in auctions in which the bidders' final utility possibly depends on the winner's identity. We show that such direct externalities offer a possible explanation for cartels'structures (not) observed in practice.Core; partition function game; Collusion; Auctions; Bayesian game;

Core-stable rings in second price auctions with common values.

In a commonvalueauction in which the information partitions of the bidders are connected, all rings are core-stable. More precisely, the ex ante expected utilities of rings, at the (noncooperative) sophisticated equilibrium proposed by Einy et al. [Einy, E., Haimanko, O., Orzach, R., Sela, A., 2002. Dominance solvability of second-pricesauctions with differential information. Journal of Mathematical Economics 37, 247–258], describe a cooperative games in characteristic function form, in spite of the underlying strategic externalities. A ring is core-stable if the core of this characteristic function is not empty. Furthermore, every ring can implement its sophisticated equilibrium strategy by means of an incentive compatible mechanism. An example shows that, if the bidders’ information partitions are not connected, rings may no longer be core-stable.Characteristic function; Partition form game; Core; Collusion; Bayesian game; Auctions;

Core-stable Rings in Second Price Auctions with Common Values

In a common value auction in which the information partitions of the bidders are connected, all rings are core-stable. More precisely, the ex ante expected utilities of rings, at the (noncooperative) sophisticated equilibrium proposed by Einy, Haimanko, Orzach and Sela (Journal of Mathematical Economics, 2002), describe a cooperative game, in characteristic function form, in spite of the underlying strategic externalities. A ring is core-stable if the core of this characteristic function is not empty. Furthermore, every ring can implement its sophisticated equilibrium strategy by means of an incentive compatible mechanism.Auctions, Bayesian Game, Collusion, Core, Partition Form Game, Characteristic Function