A derivation of the money Rawlsian solution

We study the set of envy-free allocations for economies with indivisible objects and quasi-linear utility functions. We characterize the minimal amount of money necessary for its nonemptiness when negative distributions of money are not allowed. We also find that, when this is precisely the available amount of money, there is a unique way to combine objects and money such that these bundles may form an envy-free allocation. Based on this property, we describe a solution to the envy-free selection problem following a pseudo-egalitarian criterion. This solution coincides with the Money Rawlsian Solution proposed by Alkan et al. (1991).I am indebted to I. Gilboa for his valuable suggestions and his patience during the elaboration of the final version. I also wish to thank S. Barbera for his guidance in an earlier version and M. Boldrin, H. Moulin, Z. Neeman, W. Thomson and the referees for their comments. Financial support from FPU-MEC (Spain) is gratefully acknowledged.Northwestern University.     

POLITICAL REPUTATIONS AND CAMPAIGN PROMISES

We analyze conditions under which candidates' reputations may affect voters' beliefs over what policy will be implemented by the winning candidate of an election. We develop a model of repeated elections with complete information in which candidates are purely ideological. We analyze an equilibrium in which voters' strategies involve a credible threat to punish candidates who renege on their campaign promises and in which all campaign promises are believed by voters and honored by candidates. We characterize the maximal credible campaign promises and find that the degree to which promises are credible in equilibrium is an increasing function of the value of a candidate's reputation. (JEL: D8)     

Risk Perception Among Smokers: A Qualitative Study

The aim of this qualitative study is to identify the dimensions people used to assess the risk of smoking and then compare them with those used by health professionals in primary healthcare. Five discussion groups were conducted. The field work was carried out in Barcelona (Spain), from February 2005 to January 2006. Data were analyzed following a semantic‐thematic categorical content analysis (ACC‐ts). Results showed that people tend to employ stereotypical discourses when evaluating the risk of smoking. Similarly, they reassess the risk in the context of their life experience and incorporate new nuances to the arguments sustaining their behavior. Once this reassessment takes place, the decision to continue smoking emerges, and smokers come up with additional arguments justifying their habit (i.e., age, benefits related to costs). Professionals are aware of this process and its multidimensional nature. Nevertheless, their discourse loses this multidimensional feature when discussing the strategies they use at smoking cessation interventions. This qualitative study increases the understanding of various meanings that people attribute to their life experience. These assumptions may be useful for developing health practices that are closer to people. As a practical utility of these results, it would be interesting to apply a preliminary assessment of the different meanings that people attribute to smoking from their life context in risk communication.     

Making statements and approval voting

We assume that people have a need to make statements, and construct a model in which this need is the sole determinant of voting behavior. In this model, an individual selects a ballot that makes as close a statement as possible to her ideal point, where abstaining from voting is a possible (null) statement. We show that in such a model, a political system that adopts approval voting may be expected to enjoy a significantly higher rate of participation in elections than a comparable system with plurality rule.     

The Challenge of Activist Coalition Governance: Accommodating Diversity to Create Institutions—An Approach Via the Inter-Relationships Between Action,Project and Instrument

This paper addresses the governance of hybrid forms of organisation arising in new social movements, characterised by diverse institutional logics and democratic decision making. Our theoretical framework encompasses the governance theory of Kooiman with insights from new developments in institutional theory. This framework allows us to examine governance as the capacity to link together disparate institutions from the perspective of interactions between action, project and instrument, and to explore the institutional work that results from these interactions. By studying a French activist coalition, we explore the micro-processes that make it possible to accommodate diversity in an organisation intended to produce solid institutions. Our results show that the three elements of governance—action, project and instrument—have an impact on the cohesion of diversity-based organisations and on building and consolidating institutions. When these elements are flexible and versatile enough, and when they mutually nurture each other, a plurality of logics is possible, the coalition goes forward, and true institutional work can be accomplished. When one of these elements of governance—instruments in particular—becomes autonomous and rigid, diversity is more difficult to achieve and one logic is likely to prevail over the others, compromising the very survival of the coalition and impeding the emergence of a new institution.     

Holt-Winters Forecasting: An Alternative Formulation Applied to UK Air Passenger Data

This paper provides a formulation for the additive Holt-Winters forecasting procedure that simplifies both obtaining maximum likelihood estimates of all unknowns, smoothing parameters and initial conditions, and the computation of point forecasts and reliable predictive intervals. The stochastic component of the model is introduced by means of additive, uncorrelated, homoscedastic and Normal errors, and then the joint distribution of the data vector, a multivariate Normal distribution, is obtained. In the case where a data transformation was used to improve the fit of the model, cumulative forecasts are obtained here using a Monte-Carlo approximation. This paper describes the method by applying it to the series of monthly total UK air passengers collected by the Civil Aviation Authority, a long time series from 1949 to the present day, and compares the resulting forecasts with those obtained in previous studies.     

Forecasting time series with missing data using Holt's model

This paper deals with the prediction of time series with missing data using an alternative formulation for Holt's model with additive errors. This formulation simplifies both the calculus of maximum likelihood estimators of all the unknowns in the model and the calculus of point forecasts. In the presence of missing data, the EM algorithm is used to obtain maximum likelihood estimates and point forecasts. Based on this application we propose a leave-one-out algorithm for the data transformation selection problem which allows us to analyse Holt's model with multiplicative errors. Some numerical results show the performance of these procedures for obtaining robust forecasts.