French Representations of Citizenship and Immigrants: The Political Dimension of the Civic Link

Representations of, and attitudes towards, foreigners take place within the complex system of values and meaning that constitutes what we call a national identity. In the French case, different conceptions of citizenship give rise to different attitudes towards immigrants. These conceptions, even if they could be related to antagonistic theories of democracy, blend together within the citizens' representations, giving the opportunity to combine advantages from each model, namely cohesion and inclusion. But the mix of citizenship representations occurs successfully only when the political dimension of citizenship is accepted. Where this is not the case, the antagonistic potential of both understanding of citizenship and immigrants develops and endangers the coherence of the civic and political national culture.     

Modeling Uncertainties in Mining Pillar Stability Analysis

Many countries are now facing problems related to their past mining activities. One of the greatest problems concerns the potential surface instability. In areas where a room-and-pillar extraction method was used, deterministic methodologies are generally used to assess the hazard of surface collapses. However, those methodologies suffer from not being able to take into account all the uncertainties inherent in any hazard analysis. Through the practical example of the assessment of a single pillar stability in a very simple mining layout, this article introduces a logical framework that can be used to incorporate the different kinds of uncertainties related to data and models, as well as to specific expert's choices in the hazard or risk analysis process. Practical recommendations and efficient tools are also provided to help engineers and experts in their daily work.     

A History of Threat in Europe and Belgium (1920–1993)

A general index of social, economic, and political threat in Europe and Belgium was developed for the years 1920 to 1993. We asked 91 Belgian historians, experts in contemporary history, to rate, on 7-point intensity scales, the extent to which each year, between 1920 to 1993, the security and existence of either Europe or Belgium was threatened. In making their judgments, the historians must integrate most of the information contained in objective data known to them as causes of fear (crime, unemployment, apprehension at starting a family, buying a car, or starting a new business, etc.). The present threat index rests on a synthetic judgment because many official objective data available to historians either are incomplete or lack conceptual coherence. The index obtained has then been compared to known objective indicators of social, economic, or political threat. We obtained Cronbach's coefficients of 0.99 for Belgian historians. Corrected for serial dependency, the threat index for Belgium is found to depend on a 5-variable subset composed of: suicide, unemployment, and balance of trade, for the positive associations; and GNP and car registrations, for the negative associations. The Pearson correlation between the threat index for Europe and Belgium is 0.95 (N = 74, p < 0.001). Just as McCann and Stewin (1990) had developed a similar tool for North America, the aim of this multi-purpose tool was to monitor the mood of Europe and Belgium over time based on evaluations made by professional historians. McCann and Stewin's (1990) threat index for the US has a Pearson correlation of 0.65 (N = 67, p < 0.001) with the European threat index. The article concludes with a discussion first on the question of the role of threat producing discourses in the perception of threat, and second, on the question of Europe as a concept.     

Panel Binary Variables and Sufficiency: Generalizing Conditional Logit

This paper extends the conditional logit approach (Rasch, Andersen, Chamberlain) used in panel data models of binary variables with correlated fixed effects and strictly exogenous regressors. In a two‐period two‐state model, necessary and sufficient conditions on the joint distribution function of the individual‐and‐period specific shocks are given such that the sum of individual binary variables across time is a sufficient statistic for the individual effect. By extending a result of Chamberlain, it is shown that root‐n consistent regular estimators can be constructed in panel binary models if and only if the property of sufficiency holds. In applied work, the estimation method amounts to quasi‐differencing the binary variables as if they were continuous variables and transforming a panel data model into a cross‐section model. Semiparametric approaches can then be readily applied.     

Formal and Informal Risk Sharing in LDCs: Theory and Empirical Evidence

We develop and estimate a model of dynamic interactions in which commitment is limited and contracts are incomplete to explain the patterns of income and consumption growth in village economies of less developed countries. Households can insure each other through both formal contracts and informal agreements, that is, self‐enforcing agreements specifying voluntary transfers. This theoretical setting nests the case of complete markets and the case where only informal agreements are available. We derive a system of nonlinear equations for income and consumption growth. A key prediction of our model is that both variables are affected by lagged consumption as a consequence of the interplay of formal and informal contracting possibilities. In a semiparametric setting, we prove identification, derive testable restrictions, and estimate the model with the use of data from Pakistani villages. Empirical results are consistent with the economic arguments. Incentive constraints due to self‐enforcement bind with positive probability and formal contracts are used to reduce this probability.     

Capturing the re-admission process: focus on time window

In the majority of studies on patient re-admissions, a re-admission is deemed to have occurred if a patient is admitted within a time window of the previous discharge date. However, these time windows have rarely been objectively justified. We capture the re-admission process from the community using a special case of a Coxian phase-type distribution, expressed as a mixture of two generalized Erlang distributions. Using the Bayes theorem, we compute the optimal time windows in defining re-admission. From the national data set in England, we defined re-admission for chronic obstructive pulmonary disease (COPD), stroke, congestive heart failure, and hip- and thigh-fractured patients as 41, 9, 37, and 8 days, respectively. These time windows could be used to classify patients into two groups (binary response), namely those patients who are at high risk (e.g. within 41 days for COPD) and low risk of re-admission group (respectively, greater than 41 days). The generality of the modelling framework and the capability of supporting a broad class of distributions enables the applicability into other domains, to capture the process within the field of interest and to determine an appropriate time window (a cut-off value) based on evidence objectively derived from operational data.     

Random walk Green kernels in the neutral Moran model conditioned on survivors at a random time to origin

In the theory of finite discrete-time birth and death chains with absorbing endpoint boundaries, the evaluation of both additive and multiplicative path functionals is made possible by their Green and λ–potential kernels. These computations are addressed in the context of such Markov chains. The application to the neutral Moran model of population genetics yields first hitting and return times. A neutral Moran bridge model, forward and backward in time, for a given total number x of survivors of a single common ancestor at some random time T to the origin of times, yields the age of a mutant allele currently observed to have x copies of itself. This forward theory of age, made possible by Green kernels, is comparable to Watterson’s backward theory of age, which makes use of the reversibility of the Moran chain.