Tribute to Jean-Yves Jaffray

Tribute to Jean-Yves Jaffray by the French Group of Decision Theory.     

Measuring socioeconomic status in health research in developing countries: Should we be focusing on households,communities or both?

Research on the effects of socioeconomic well-being on health is important for policy makers in developing countries, where limited resources make it crucial to use existing health care resources to the best advantage. This paper develops and tests a set of measures of socioeconomic status indicators for predicting health status in developing countries. We construct socioeconomic indexes that capture both household and community attributes so as to allow us to separate the social from the purely economic dimensions of the socioeconomic status within a cross-national perspective, with applications to data from Demographic and Health Surveys (DHS) fielded in five African countries in the 1990s. This study demonstrates the distinctive contributions of socioeconomic indexes measured at the household vs. community level in understanding inequalities in health and survival and underlines the importance of going beyond the purely economic view of socioeconomic status to cover the multidimensional as well as multilevel concept of economic and social inequality.     

Information and capacities

Most economists consider that the cases of negative information value that non-Bayesian decision makers seem to exhibit, clearly show that these models are not models representing rational behaviour. We consider this issue for Choquet Expected Utility maximizers in a simple framework, that is the problem of choosing on which event to bet. First, we find a necessary condition to prevent negative information vlaue that we call Separative Monotonicity. This is a weaker condition than Savage Sure thing Principle and it appears that necessity and possibility measures satisfy it and that we cand find conditioning rules such that the information value is always positive. In a second part, we question the way information value is usually measured and suggest that negative information values are merely resulting from an inadequate formula. Yet, we suggest to impose what appears as a weaker requirement, that is, the betting strategy should not be Statistically Dominated. We show for classical updating rules applied to belief functions that this requirement is violated. We consider a class of conditioning rules and exhibit a necessary and sufficient condition in order to satisfy the Statistical Dominance criterion in the case of belief functions. Received: November 2000; revised version: July 2001     

Decisions with conflicting and imprecise information

When facing situations involving uncertainty, experts might provide imprecise and conflicting opinions. Recent experiments have shown that decision makers display aversion towards both disagreement among experts and imprecision of information. We provide an axiomatic foundation for a decision criterion that allows one to distinguish on a behavioral basis the decision maker’s attitude towards imprecision and disagreement. This criterion accommodates patterns of preferences observed in experiments that are precluded by two-steps procedures, where information is first aggregated, and then used by the decision maker. This might be seen as an argument for having experts transmitting a more detailed information to the decision maker.     

Validity evidence of the Portuguese adaptation of the Ambivalent Sexism Inventory / Evidencias de validez de la adaptación portuguesa de la Escala de Sexismo Ambivalente

Abstract

Modern forms of sexism have promoted the development of new scales and evaluation tools. The Ambivalent Sexism Inventory (ASI) (Glick & Fiske, 1996) aims to assess sexism along two dimensions: hostile sexism and benevolent sexism. The aim of this study is to present evidence of the validity of the factor structure of the Portuguese version of the ASI by analysing its structure and its relationships with neosexism and social dominance. The sample consisted of 446 Portuguese participants (68.6% female) between 17 and 77 years old. Results confirmed the two-factor structure; however, the best fit was registered with a four-factor structure: one hostile factor and three benevolent factors. Both hostile and benevolent sexism were correlated with neosexism and social dominance orientation. Future research should explore the dimensionality of the scale based on a four-dimension structure and its relationship to others sexism issues.     

Defining the Creole City by Walking: The Case of La Réunion

ABSTRACT

This paper presents exploratory work to understand the characterisation of the ‘Creole city’ inLa Réunion, through an analysis of three renovated districts. The purpose is to inform urbanrenewal programmes so that they take better account of local lifestyles and needs. Theresearch on representations and symbols involves a method to collect and analyse data thatcombines in situ situations and a strong day-to-day approach, namely, walking. This method,that may be used elsewhere, reveals the functioning qualities of traditional Creole cities as anurbanity that is adapted to its environment, and based on proximity and soft transport modes.     

Street trees in Paris are sensitive to spring and autumn precipitation and recent climate changes

Urban Ecosystems - Determining the main factors causing urban tree decline is becoming essential for sustaining their health and survival. Understanding responses of tree growth to urban...     

An experimental investigation of imprecision attitude and its relation with risk attitude and impatience

We report in this article the result of three experiments on risk, ambiguity, and time attitude. The first two differed by the population considered (students vs. general population) while the third one used a different protocol and concerned students and portfolio managers. We find quite a lot of heterogeneity at the individual level. Of principal interest was the elicitation of risk, time, and ambiguity attitudes and the relationship among these (model free) measures. We find that on the student population, there is essentially no correlation. A non-negligible fraction of the population behaves in an extremely cautious manner in the risk and ambiguity domain. When we drop this population from the sample, the correlation between our measures is also non-significant. We also raise three questions linked to measurement of ambiguity attitudes that come out from our data sets.