Maximum likelihood approach to vote aggregation with variable probabilities

The Condorcet-Kemeny-Young statistical approach to vote aggregation is based on the assumption that voters have the same probability of comparing correctly two alternatives and that this probability is the same for any pair of alternatives. We relax the second part of this assumption by letting the probability of comparing correctly two alternatives be increasing with the distance between two alternatives in the allegedly true ranking. This leads to a rule in which the majority in favor of one alternative against another one is given a larger weight the larger the distance between the two alternatives in the true ranking, i.e., the larger the probability that the voters compare them correctly. This rule is not Condorcet consistent and does not satisfy local independence of irrelevant alternatives. Yet, it is anonymous, neutral, and paretian. It also appears that its performance in selecting the alternative most likely to be the best improves with the rate at which the probability increases.We would like to thank Michel Le Breton for his encouragement to examine this question and for his comments, as well as Philippe De Donder, Jean-Yves Duclos, Stephen Gordon, Cyril Téjédo and an anonymous referee for their comments.     

A limit theorem on the dual core of a distributive social system

I consider abstract social systems where the distribution of wealth is an object of common concern. I study, in particular, the systems where liberal distributive social contracts consist of the Pareto-efficient distributions that are unanimously preferred to the initial distribution. I define a Dual Distributive Core from a process of decentralized auction on the budget shares of Lindahl associated with net transfers, operated by coalitions aiming at increasing the value of the public good for their members while maintaining their utility levels. I establish that the dual distributive core converges, as the number of distributive agents becomes large relative to the number of agent types, to a typically finite number of distributive liberal social contracts, which correspond to the Lindahl equilibria that are unanimously preferred to the initial distribution. This process of decentralized auction provides a theoretical foundation for contractual policies of redistribution. The comparison with the usual notion of core with public goods (Foley 1970) yields the following results in this context: the Foley-core is a subset, generally proper, of the set of liberal distributive social contracts; it does not contain, in general, distributive Lindahl equilibria.     

Awareness Promotion About Excessive Gambling Among Video Lottery Retailers

This paper describes and evaluates “As luck would have it,” an awareness program completed by retailers in Quebec Province. This program, which is presented as a two-hour awareness promotion workshop, aimed to inform retailers about excessive gambling. More specifically, it provided answers to the following questions: (1) What is chance and randomness? (2) Is there a link between misunderstanding the concept of chance and excessive gambling? (3) How does one recognise the symptoms of this disorder? (4) How should retailers intervene if they decide to do so? Results showed that retailers developed a better understanding of problem gambling, could recognise its main symptoms, felt more capable of coping with excessive gamblers, and of choosing the most appropriate moment to do so. In the follow-up phase, retailers who had attended the workshop reported that they approached a problem gambler significantly more often than the retailers who had not attended the workshop, and had discussed how to help problem gamblers significantly more often. The practical implications of these results are briefly discussed.     

The role of teacher relationships in the lives of students

This chapter examines positive teacher-student relationships, as seen through a variety of psychological models and provides recommendations for schools and teachers.     

The critical ingredient: caring youth-staff relationships in after-school settings

After-school settings are interpersonal in nature, and the quality of the relationships that are forged can directly influence youths' attendance decisions and the developmental benefits they derive. Programs should more effectively capitalize on this potential for caring adult-staff relationships.     

Strategic management of public and non-market corporations

The author has developed a strategic framework for the management of ‘non-market corporations’ which he thinks better meets their peculiarities and specific needs by framing them in a relatively tight and rigorous socio-economic system relating to their internal logic. He believes that the proposed approach should provide the basis for a more constructive relationship between such corporations and the community at large and for better levels of performance     

The dynamics of the population sex ratio in India, 1971-96

This paper reconstructs the trend in the population sex ratio in India between 1971 ad 1996 from available information on changes in sex differentials in mortality in the country since the beginning of the century. It is estimated that, although the mortality of females relative to that of males in India has improved since 1968, the population sex ratio increased between 1971 and 1981, stayed constant between 1981 and 1991, and started to decrease only after 1991. This implies that the recorded decrease and increase in the periods 1971-81 and 1981-91 respectively were both spurious and were the results of undercounts of females in 1971 and 1991. Another implication of this finding is that, owing to the lagged effect of past mortality on current trends in the population sex ratio, this ratio is a bad proxy for use in the study of changes in differential mortality by sex.     

Upper Bounds for the SPOT 5 Daily Photograph Scheduling Problem

This paper introduces tight upper bounds for the daily photograph scheduling problem of earth observation satellites. These bounds, which were unavailable until now, allow us to assess the quality of the heuristic solutions obtained previously. These bounds are obtained with a partition-based approach following the divide and pas conquer principle. Dynamic programming and tabu search are conjointly used in this approach. We present also simplex-based linear programming relaxation and a relaxed knapsack approach for the problem.     

The Economic Efficiency of Sampling Size: The Case of Beef Trim

The economically optimal sample size in a food safety test balances the marginal costs and marginal benefits of increasing the sample size. We provide a method for selecting the sample size when testing beef trim for Escherichia coli O157:H7 that equates the averted costs of recalls and health damages from contaminated meats sold to consumers with the increased costs of testing while allowing for uncertainty about the underlying prevalence rates of contamination. Using simulations, we show that, in most cases, the optimal sample size is larger than the current sample size of 60 and, in some cases, it exceeds 120. Moreover, lots with a lower prevalence rate have a higher expected damage because contamination is more difficult to detect. Our simulations indicate that these lots have a higher optimal sampling rate.