Bargaining with reasonable aspirations

Consider bargaining situations with two persons, where both have a specific idea of what would be an equitable outcome. In case these ideas differ, a procedure is needed which leads to a compromise between the different views. In the present paper the axioms of restricted homogeneity and of relative monotonicity are introduced, each of which, together with other standard conditions, allows one to determine a solution for this class of bargaining problems. An extension of this solution to bargaining problems with more than two persons is formulated.     

Separability tests for high-dimensional,low-sample size multivariate repeated measures data

Longitudinal imaging studies have moved to the forefront of medical research due to their ability to characterize spatio-temporal features of biological structures across the lifespan. Valid inference in longitudinal imaging requires enough flexibility of the covariance model to allow reasonable fidelity to the true pattern. On the other hand, the existence of computable estimates demands a parsimonious parameterization of the covariance structure. Separable (Kronecker product) covariance models provide one such parameterization in which the spatial and temporal covariances are modeled separately. However, evaluating the validity of this parameterization in high dimensions remains a challenge. Here we provide a scientifically informed approach to assessing the adequacy of separable (Kronecker product) covariance models when the number of observations is large relative to the number of independent sampling units (sample size). We address both the general case, in which unstructured matrices are considered for each covariance model, and the structured case, which assumes a particular structure for each model. For the structured case, we focus on the situation where the within-subject correlation is believed to decrease exponentially in time and space as is common in longitudinal imaging studies. However, the provided framework equally applies to all covariance patterns used within the more general multivariate repeated measures context. Our approach provides useful guidance for high dimension, low-sample size data that preclude using standard likelihood-based tests. Longitudinal medical imaging data of caudate morphology in schizophrenia illustrate the approaches appeal.     

Psychopathology of transvestism and transsexualism

Vaginismus being a reaction of avoidance of an anxiety‐producing situation, is readily amenable to treatment by systematic desensitization. This may proceed in two main ways: “in vitro” or “in vivo”. In order to strengthen and speed‐up the desensitization process, we used hypnotic techniques in a dynamic approach.

The first session of both methods is dedicated to building an adequate doctor‐couple relationship, careful history‐taking and dissipation of myths and fallacies regarding sexuality or hypnosis. Any attempts at sexual intercourse are forbidden at this stage.

The “in vitro” treatment proceeds with the imagery, under hypnosis, of an “anxiety hierarchy” of increasingly erotic and sexually intimate situations, which will be reproduced at home with the partner, until sexual intercourse is achieved. In the “in vivo” method the patient learns self‐hypnosis and then inserts into her vagina first her finger, then Hegar dilators of gradually increasing size. The partner, the patient and the physician will then successively proceed to the insertion, forming a team work situation. This continues until the “female superior position”, practiced first with the largest dilator, is reproduced at home by intercourse.     

Probabilities for separating sets of order statistics

Consider a set of order statistics that arise from sorting samples from two different populations, each with their own, possibly different distribution functions. The probability that these order statistics fall in disjoint, ordered intervals and that of the smallest statistics, a certain number come from the first populations is given in terms of the two distribution functions. The result is applied to computing the joint probability of the number of rejections and the number of false rejections for the Benjamini-Hochberg false discovery rate procedure.     

Tenancy,Marriage, and the Boll Weevil Infestation, 1892–1930

In the early twentieth century, the cotton-growing regions of the U.S. South were dominated by families of tenant farmers. Tenant farming created opportunities and incentives for prospective tenants to marry at young ages. These opportunities and incentives especially affected African Americans, who had few alternatives to working as tenants. Using complete-count Census of Population data from 1900–1930 and Census of Agriculture data from 1889–1929, we find that increases in tenancy over time increased the prevalence of marriage among young African Americans. We then study how marriage was affected by one of the most notorious disruptions to southern agriculture at the turn of the century: the boll weevil infestation of 1892–1922. Using historical Department of Agriculture maps, we show that the boll weevil’s arrival reduced the share of farms worked by tenants as well as the share of African Americans who married at young ages. When the boll weevil infestation altered African Americans’ opportunities and incentives to marry, the share of African Americans who married young fell accordingly. Our results provide new evidence about the effect of economic and political institutions on demographic transformations.     

Introduction: Globalisation and identity

Abstract

This paper examines the identities of early leaders of the African National Congress (ANC) at a time when British influences still prevailed in South Africa. African attitudes to the “British World” reveal complex identities that also reflected political and cultural variations according to race, class and region. Relations between ANC leaders and the African “elite” and between the elite and subaltern strata were not straightforward. A careful reading of the discourses in and around Congress points to contradictory attitudes to things British and to ambiguous identities that lingered and contributed to the mix of social and national ideas and identities that influence contemporary South Africa.     

Body mass index, academic achievement, and school context: examining the educational experiences of adolescents at risk of obesity

Reflected self-appraisal suggests that individual functioning is related to the fit between individual characteristics and the norms of their primary contexts. To apply this social psychological concept to the study of obesity, we hypothesized that adolescents at risk of obesity would have lower academic achievement overall than other students, especially in schools in which their weight status was most likely to elicit negative evaluations. Multi-level modeling of nationally representative data revealed that the negative longitudinal association between risk of obesity and achievement was stronger in schools with higher rates of romantic activity and lower average body size among students, two school contexts in which obesity was likely to be stigmatized, but weaker in schools with higher rates of athletic participation, a school context in which such stigmatization was also likely. Additional analyses suggested that this last, unexpected finding reflected a process of niche-picking.     

Reputation, trust and the dynamics of leadership in communities of practice

The aim of this article is to propose a theoretical framework describing the internal organization of communities of practice in a dynamic perspective. More precisely, we argue that communities of practice adopt some specific patterns of internal organization where some of their members obtain a leadership status. Leaders contribute to cognitive advance of the community of practice by providing members with a consistent and coherent vision of its objectives. We identify two of their attributes as important for allowing them to fulfil their task: informational mimesis and mediation. Finally, we propose a simulation model describing the emergence of leadership as the outcome of a self-organizing process. We find that leaders correspond to members who are characterized by higher levels of activity in the community.This work has greatly benefited from comments by participants at the 3^rd ETE Workshop held in Sophia-Antipolis. Comments by Markus Becker, Antoine Bureth, Patrick Cohendet, Robin Cowan, Christophe Lerch, Julien Pénin are gratefully acknowledged. Remarks by two anonymous reviewers and the editor contributed to improve significantly the quality of the article. The usual disclaimer applies.     

A theorem on utilitarian redistribution

A theorem is presented which characterizes regions where the marginal utilities of most goods decrease with increasing utility, given non-inferiority of one good and a strictly concave utility function. An analysis of the optimum utilitarian tax rests on this result.I am grateful to Josef Falkinger and Bengt-Arne Wickström for helpful comments. A previous version of the paper was written when the author visited Oxford University, Wolfson College.