Showing papers by "School for Advanced Studies in the Social Sciences published in 1985"

Planning Under Incomplete Information and the Ratchet Effect.

Abstract: : Central Planning of production is usually performed under asymmetric information. The firm in general has more information about its productive possibilities than the Central Planner (from now on for short CP). This justifies the use of incentives schemes in which the CP does not directly fix activity levels. Casual observation of such existing schemes suggests that the time dimensions is crucial for their working. Typically the CP revises the incentive scheme over time to take into account the information provided by the firm's performance. Managers of centrally planned economies as well as economists have long recognized that this revision induces firms to underproduce in order to avoid demanding schemes in the future. This is the ratchet effect. It is purpose of the present paper to study the ratchet effect under the non-commitment assumption, which we believe to be more realistic, The inadequacy of conceptual tools made if difficult in the past to consider such an assumption. Now basic research on dynamic games with incomplete information recently resulted in new ideas which look particularly relevant for a theoretical analysis of the problem.

A characterization of planar graphs by trémaux orders

Abstract: A new characterization of planar graphs is stated in terms of an order relation on the vertices, called the Tremaux order, associated with any Tremaux spanning tree or Depth-First-Search Tree. The proof relies on the work of W. T. Tutte on the theory of crossings and the Tremaux algebraic theory of planarity developed by P. Rosenstiehl.

From visual-motor anticipation to conceptualization: Reaction to solid and hollow objects and knowledge of the function of containment

Abstract: This research investigates the development of visual-manual coordination during infancy with respect to the spatial property of concavity and the development of the capacity to expect or understand that a hollow object affords specific manual behaviors. Tumblers closed at the top by a plexiglas plate were used: They seemed to be open but resisted introduction of the hand. Infants' behavior towards these deceptive objects was compared with their behavior towards identical objects that looked and felt closed or open. The results show that from the 8th month infants exhibit to the deceptive objects an anticipatory visuomotor behavior and from ninth month they exhibit exploratory behavior that suggests that they are trying to understand the discrepancy between the objects' visual and tactile properties. It can therefore be concluded that a rudimentary conceptualization of containment appears to be elaborated by infants from ninth month.

Signification et fonctionnement du concept de variable informatique chez des eleves debutants

Abstract: Dans le cadre d'une problematique d'ensemble sur les difficultes cognitive posees par l'acquisition des concepts informatiques, nous avons etudie chez des eleves debutants, la resolution de problemes relatifs a la representation et au traitement des variables informatiques, dans une tâche de completion de lignes manquantes dans un programme. Les resultats permettent de discuter les relations entre d'une part la nature des solutions apportees par les eleves, d'autre part les proprietes du champs conceptuel en jeu et la maniere dont les concepts ont ete introduits.