Search results for " Reciprocity"
showing 10 items of 35 documents
Does Theorizing on Reciprocal Altruism Apply to the Relationships of Individuals with a Spinal Cord Injury?
2012
From the perspective of reciprocal altruism, we examined the role of reciprocity in the close relationships of people inflicted with a spinal cord injury (SCI) ( n = 70). We focused on the help receiver rather than on the help giver. Participants perceived more reciprocity in relationships with friends than in relationships with the partner and with family members. In these last relationships, perceptions of indebtedness were more prevalent than perceptions of deprivation. However, most negative feelings were evoked by a lack of reciprocity in partner relationships, followed by family relationships, and next by friendships. Moreover, depression was especially associated with a lack of perc…
Athènes et les « Philaïdes » Formes de réciprocité entre les aristocrates et la polis
2009
This article aims at exploring the relationship between Athens and the members of the Miltiades and Cimon family, the so-called Philaids. The history of this lineage significantly marked the development of Athens in the archaic period. In spite of the contradictory traditions regarding these historical figures, a lexical analysis of the sources allows an interpretation of their relationship with the polis in terms of reciprocity. I will argue that this is a special form of reciprocity, generated by the unequal and asymmetric relationship that this family seems to have had with Athens.
The legal balance between liberty and equality
2021
The paper explores the specific legal balance between liberty and equality, distinguishing it from political theories and constitutional settings, where they are often considered in opposition. In order to find the specific legal balance between liberty and equality, and after identifying some of their relevant meanings for the purpose, it becomes necessary to focus on the rule of law, and to examine the relationship between liberty and equality in its different versions. Once the core meaning of the rule of law in terms of liberty and equality is enucleated, it is possible to consider extending it to the international field.
Selection and Gratitude: Anonymity and gratitude
2018
What kind of candidate is selected into a job when the principal has to appoint a committee to measure the candidate's ability and select a winner through a call specifying a wage for the job? In a model where the principal fixes the wage anticipating the committee's choice, under a rather natural assumption about the committee's objective we find that if the committee takes into account the candidate's gratitude a candidate with less than first best ability will be selected in equilibrium. First best selection is achieved if the committee is anonymous to the candidates. If the committee could also set the wage the first best candidate would be selected, but the principal would be worse off…
Parabolic Subgroups of Artin Groups
1997
Abstract Let ( A , Σ) be an Artin system. For X ⊆ Σ, we denote by A X the subgroup of A generated by X . Such a group is called a parabolic subgroup of A . We reprove Van der Lek's theorem: “a parabolic subgroup of an Artin group is an Artin group.” We give an algorithm which decides whether two parabolic subgroups of an Artin group are conjugate. Let A be a finite type Artin group, and let A X be a parabolic subgroup with connected associated Coxeter graph. The quasi-centralizer of A X in A is the set of β in A such that β X β −1 = X . We prove that the commensurator of A X in A is equal to the normalizer of A X in A , and that this group is generated by A X and the quasi-centralizer of…
Gaussian Groups and Garside Groups, Two Generalisations of Artin Groups
1999
It is known that a number of algebraic properties of the braid groups extend to arbitrary finite Coxeter-type Artin groups. Here we show how to extend the results to more general groups that we call Garside groups. Define a Gaussian monoid to be a finitely generated cancellative monoid where the expressions of a given element have bounded lengths, and where left and right lowest common multiples exist. A Garside monoid is a Gaussian monoid in which the left and right lowest common multiples satisfy an additional symmetry condition. A Gaussian group is the group of fractions of a Gaussian monoid, and a Garside group is the group of fractions of a Garside monoid. Braid groups and, more genera…
A Strain Sensing Structural Health Monitoring System for Delaminated Composite Structures
2012
Structural Health Monitoring (SHM) for composite materials is becoming a primary task due to their extended use in safety critical applications. Different methods, based on the use of piezoelectric transducers as well as of fiber optics, has been successfully proposed to detect and monitor damage in composite structural components with particular attention focused on delamination cracks.In the present paper a Structural Health Monitoring model, based on the use of piezoelectric sensors, already proposed by the authors for isotropic damaged components, is extended to delaminated composite structures. The dynamic behavior of the host damaged structure and the bonded piezoelectric sensors is m…
On the Toeplitz algebras of right-angled and finite-type Artin groups
1999
The graph product of a family of groups lies somewhere between their direct and free products, with the graph determining which pairs of groups commute and which do not. We show that the graph product of quasi-lattice ordered groups is quasi-lattice ordered, and, when the underlying groups are amenable, that it satisfies Nica's amenability condition for quasi-lattice orders. As a consequence the Toeplitz algebras of these groups are universal for covariant isometric representations on Hilbert space, and their representations are faithful if the isometries satisfy a properness condition given by Laca and Raeburn. An application of this to right-angled Artin groups gives a uniqueness theorem …
Selection by committee: Anonymity and gratitude
2018
Abstract What kind of candidate is selected into a job when the principal has to appoint a committee to measure the candidates’ ability and select a winner? We find that if the committee takes into account the candidate’s gratitude towards them, a candidate with less than first best ability will be selected. A relevant exception may occur if the first best is the overall best candidate. First best selection is always achieved if the committee is anonymous to the candidates. If the committee is not detached enough from the candidates then delegation fares even worse than random selection.
On the dynamic behavior of piezoelectric active repair by the boundary element method
2011
The dynamic behavior of piezoelectric active repair bonded on cracked structures is analyzed in this article. The boundary element code used to perform the simulations is implemented in the framework of piezoelectricity in order to model the coupling between the elastic and the electric fields, which represents the most important feature of piezoelectric media. The fracture mechanics problem, i.e. the crack, as well as the bonding layer between the host structure and the active patch is modeled by means of the multidomain technique provided with an interface spring model. More particularly, the spring interface model allows considering the bonding layer as a zero-thickness elastic ply char…