Linear programming and financial cost models for industrial enterprises

Linear programming models of complex interrelated manufacturing enterprises have improved production planning decisions. With a linear programming formulation, the planning engineer concerned with specifying levels of production activity need not be concerned with cost accounting formulations of product costs to make his production decisions. He is only concerned with examining alternative production activities in terms of the added production costs the activity incurs, and the amount of product that is fed or consumed. The financial analyst, however, is concerned with development of budgetted average product costs. He must roll the costs of feed and intermediate products down to the final stage products. This paper bridges these two interests by demonstrating a methodology for the direct translation of the solution of the linear programming model to the development of rolled product standard costs.     

Les poubelles du Québec: d'un enjeu de groupe de pression à un enjeu de mouvement social

How has the problem of solid waste and its management become a major socio-political issue in Quebec? Our research identifies the main dimensions of this social question. It presents, on the one hand, quantitative data concerning this subject and, on the other, an analysis of certain recent collective actions that have taken place in Montreal and elsewhere in Quebec. Our study shows how such collective actions characterize social conflict and become part of a socio-political issue—that surrounding solid waste and its management. Our research demonstrates that the socio-political issue of waste management is not only a question revolving around the actions of pressure groups, but that it extends to collective action characteristic of social movements. That is why Quebec's garbage cans represent a socio-political issue capable of profoundly influencing society in the near future. Comment le problème des déchets solides et celui de leur gestion sociale sont-ils devenus un enjeu sociopolitique d'envergure au Québec? Notre recherche précise les principales dimensions de cette question sociale en présentant d'une part les données quantitatives sur le sujet et, d'autre part, une analyse de certaines actions collectives récentes, à Montréal et ailleurs au Québec, qui constituent en luttes sociales, puis en enjeu sociopolitique, le problème des déchets solides et de leur gestion. La recherche démontre que l'enjeu sociopolitique que constituent les déchets n'est alors plus une question relevant uniquement de différents groupes de pression, mais qu'il s'étend plutôt à des pratiques caractéristiques d'un mouvement social. C'est pourquoi les poubelles du Québec représentent, à plu-sieurs égards, un enjeu sociopolitique capable de marquer profondé-ment le devenir de notre société.     

La « perruque » en usine : approche d’une pratique marginale, illégale et fuyante

A “homer” is an artifact that a worker produces using company tools and materials outside normal production plans but at the workplace and during workhours. Despite legal, artistic and ethnographic evidence of their existence, silence surrounds homers. Along with this evidence, interviews conducted mostly with retirees from a French aeronautics plant are used to show that this silence is not linked just to the marginal and illegal quality of these artifacts. Homers shed light on a high degree of “complicity” between employees regardless of their position in the hierarchy. Since the factory’s institutional framework has little room for this complicity, the silence surrounding homers is a sign probably of an inability to talk about them rather than of their marginality or illegality.     

Confrontation des Statistiques de migrations intra-européennes: Vers plus d'harmonisation?

Each international migration stream can be enumerated twice: at the time of departure from the country of emigration and at the time of arrival in the country of immigration. In practice, errors in international migration statistics are a major obstacle to the accurate analysis of migration flows. In connection with the process of harmonization set in train by Eurostat several years ago, a method of correcting defective migration data is proposed here, which makes use of this double enumeration. The method is applied to available data in a preliminary analysis. The correction factors presented here through this mathematical approach should turn out to be useful in more than one respect: to illuminate substantial problems of incompatibility of migration data and to follow the progress of the harmonization of those data.     

Road trafficking description and short term travel time forecasting,with a classification method

The purpose of this work is, on the one hand, to study how to forecast road trafficking on highway networks and, on the other hand, to describe future traffic events. Here, road trafficking is measured by vehicle velocities. The authors propose two methodologies. The first is based on an empirical classification method, and the second on a probability mixture model. They use an SAEM‐type algorithm (a stochastic approximation of the EM algorithm) to select the densities of the mixture model. Then, they test the validity of their methodologies by forecasting short term travel times.     

Private and public pension schemes: Elements of a comparative approach

The comparative approach offers improved understanding of what is at stake for enterprises, workers and States in developing private pension schemes to fill the gap left by public schemes. The features that distinguish private schemes result from the freedom with which they were designed — by enterprises themselves or through collective bargaining — and the limits imposed by growing state intervention in granting fiscal concessions or stipulating social guarantees. Depending on how these various components are combined, private schemes may offers workers added protection or form a source of insecurity.     

Time preference and labour migration in an OLG model with land and capital

This paper constructs a two-country migration model in the lines of Galor (1986), in which the world population consists of individuals of two types who have different time preferences. Production uses three inputs: mobile labour, immobile capital and land. It is shown that both countries are necessarily inhabited by agents of both types and exhibit equal density of population and equal interest rate at the steady state equilibrium of the integrated economy. The steady state welfare implications of international labour migration are studied.This paper has been written during Philippe Michel's visit at CORE, September 1994. Earlier drafts of this paper have been presented at the meeting Journées d'étude générations imbriquées (Marseille, November 24–26, 1994), at the ESPE conference (Lisbon, June 1–3, 1995) and at the EEA annual meeting (Prag, September 1–3, 1995). Comments by participants are gratefully acknowledged. We are also grateful to Stéphane Déo, Kamhon Kan, Pierre Pestieau, Christoph Schmidt and two anonymous referees for helpful comments. The usual disclaimer applies.Responsible editor: Alessandro Cigno     

An Exponential-Family Multidimensional Scaling Mixture Methodology

A multidimensional scaling methodology (STUNMIX) for the analysis of subjects' preference/choice of stimuli that sets out to integrate the previous work in this area into a single framework, as well as to provide a variety of new options and models, is presented. Locations of the stimuli and the ideal points of derived segments of subjects on latent dimensions are estimated simultaneously. The methodology is formulated in the framework of the exponential family of distributions, whereby a wide range of different data types can be analyzed. Possible reparameterizations of stimulus coordinates by stimulus characteristics, as well as of probabilities of segment membership by subject background variables, are permitted. The models are estimated in a maximum likelihood framework. The performance of the models is demonstrated on synthetic data, and robustness is investigated. An empirical application is provided, concerning intentions to buy portable telephones.