From susceptibility to frailty in social networks: The case of obesity

The obesity pandemic is represented by a discrete-time Hopfield Boolean network embedded in continuous-time population dynamics. The influence of the social environment passes through a system of differential equations, whereby obesity spreads by imitation of the most influential neighbors, those who have the highest centrality indices in the network. This property is called “homophily.” Susceptibility and frailty are redefined using network properties. Projections of the spread of obesity are validated on data collected in a French high school.     

Promoting responsible gambling via prevention messages: insights from the evaluation of actual European messages

Prevention messages are short sentences supposed to broadcast preventive intentions. Three types of messages are noticeable: messages correcting erroneous beliefs, messages informing about the risks and messages promoting responsible gambling. While the results in the literature about messages promoting results are alerting, they are frequently used in European prevention campaigns. The present study relied on language and semantics models to evaluate the communicative and preventive values of 14 messages: 7 were actual European prevention messages and 7 messages were created for the study. Overall, 339 participants answered an online questionnaire in which they evaluated the communicative value of one of the messages and then ranked all the messages according to their preventive level. Results showed that messages informing about the risks and messages correcting erroneous beliefs have a higher level of communicative value than messages promoting responsible gambling. Indeed, the latter are judged as more ambiguous and as less preventive than the two other types of messages. As models of conversational pragmatics suggest that ambiguous messages convey at least two interpretations, the article discusses the possibility that individuals comprehend these messages as incentives to control their impulses (prevention) and incentives to control the game (promotion).     

Equilibrium,affinity, dissociation constants,IC5O: Facts and fantasies

The interaction between ligands and receptors is often described in terms of 50% inhibitory concentrations (IC50). However, IC50 values do not accurately reflect the dissociation constants (Kd), and the domain of application and precision of proposed approximations for Kd estimation are unclear. The effect of affinity and of experimental conditions on the differences between IC50 and Kd has been assessed from exact mass action law calculations and from computer simulations. Competitions between [¹¹¹In]DTPA‐indium and a few metal‐DTPA complexes for binding to a specific antibody are discussed as a practical example. Exact calculations of competition assays have been implemented in Microsoft Excel and performed for a variety of concentrations of receptor, tracer, and competitor. The results are identical to those of software packages. IC50 is found larger than Kd by less than 20% only when tracer concentration is small compared with Kd and to the receptor concentration and when this receptor concentration is small compared with Kd. Otherwise, Kd and IC50 may be very different and approximations proposed in the literature to obtain Kd values from graphically derived IC50 are not acceptable as soon as the concentrations of tracer or of receptor approach Kd. Under most experimental conditions, IC50 values do not reflect Kd values. Using available software packages to determine and report Kd values would allow for more meaningful comparisons of results obtained under different experimental conditions.     

Integration of immigrants in France: a historical perspective

This article seeks to identify the different factors that have facilitated or impeded the integration of immigrants in France from a historical perspective. Its aim is to shed light on the contemporary debates on the alleged failure of the republican integration model. First, we will show that – with the formation of the nation state – the integration of migrants was a constitutive element of the social cohesion of French society. Later, and during periods of xenophobia in particular, immigrants were classified according to their ability to assimilate into the French society. Since the 1970s, the double-barrelled integration question – concerning migrants and social cohesion – has reappeared. Within this context, the ‘colour-blind’ French republican model has been challenged, primarily from an economic perspective, not only by persistent social inequalities, but also, in its quintessence, by demands for cultural recognition. These factors have reinforced racial discrimination, the success of the populist extreme right and recurrent assimilation pressure.     

On distributional change,pro-poor growth and convergence

This paper proposes a unified approach to the measurement of distributional change. The framework is used to define indices of inequality in proportional growth rates, convergence, and pro-poorness of growth and associated equivalent growth rates. A distinction is made between non-anonymous and anonymous measures. The analysis is extended by using the notion of generalized Gini index. This unified approach is then implemented to study the link between income and other non-income characteristics, such as education and health. Empirical illustrations based on Indian data on individual educational achievements and on state wide infant survival levels highlight the usefulness of the proposed measures.     

Solution of problem 5/SP08: a birth–death process with polynomial transitions Proposed by Randall J. Swift, California State Polytechnic University, Pomona, USA

Problem Section

Solution of problem 5/SP08: a birth–death process with polynomial transitions Proposed by Randall J. Swift, California State Polytechnic University, Pomona, USA     

The cross-border portability of social security benefits: Status and progress?

The importance of the cross-border portability of social benefits is increasing in parallel with the rise in the absolute number of international migrants and their share of the world population, and perhaps more importantly with the much higher and rising share of the world population that for some part of their life is working and/or retiring abroad. This article estimates how the rising stock of migrants is distributed over four key portability regimes ranging from portability through bilateral social security arrangements to undocumented workers with no access to any scheme. The comparison of estimates for 2000 and 2013 indicate a modest but noticeable increase in the share of migrants under regime I (full portability) by 1.4 per cent, but the biggest change occurred under regime III (no access to social security but also no contributions required), which almost doubled to 9.4 per cent. Regime II (potential exportability without totalization) reduced by 3.0 percentage points but remains the dominant scheme (at 53.2 per cent). The estimates suggest that the scope of regime IV (informality) reduced by 2.9 percentage points, accounting for 14.0 per cent of all migrants in 2013. This trend is positive, but more will need to be done to progress on benefit portability and various potential solutions lie outside bilateral agreements that are difficult to establish.     

“A Run-in with the Cops Is Really Few and Far Between”: Negative Evidence and Ethnographic Understanding of Racial Discrimination by Police

ABSTRACT

Statistics show that blacks are subjected to disproportionately more policing than whites, and more often interpret their encounters with police as affected by racial discrimination. The ethnographic evidence supports the numbers, but this body of work, I suggest, has been too focused on blacks’ experiences with prejudicial policing. A fruitful but largely unexplored way to advance the ethnographic study of police discrimination is to collect and analyze data from the group receiving preferential treatment from officers: whites. In practice, this often involves collecting and analyzing nonevents, such as not being stopped by police. This article’s purpose is to outline and illustrate the benefits and difficulties of such research by drawing on Lewis and Lewis’s 1980 typology of “negative evidence” and findings from my study of 30 white drug dealers.     

“Wrong place to get help”: A field experiment on luxury stores and helping behavior

Three experiments were conducted in field settings. It was hypothesized that luxury stores may act as environmental reminders of materialism and that helpfulness would vary according to the presence or absence of such cues. Study 1 (N = 80) indicated that consumers coming out of famous brand stores displayed less helpfulness, as compared to mere passersby. Study 2 (N = 112) showed passersby were less helpful near a luxury brand store than in an ordinary street with no shops. In Study 3 (N = 360), passersby were less helpful when walking down a street lined with highly exclusive stores, as compared to streets with ordinary stores or no stores. Results, limitations, and directions for future research are discussed.