De la cellule biologique à la cellule urbaine : retour sur trois expériences de modélisation multi-échelles à base d'agents

Simulating complex natural or social systems often implies to consider entitites at several levels of organisation, and take into account the way they influence each other. The choice of scales is driven by both methodological and thematic constraints which among others include the objects of significiance for the specialists, availability of relevant data for comparison, question of interest and algorithmic considerations. These multi-scale structures and the inter-levels influences can be modeled in several ways. Firstly we present three existing examples of multi-scale modeling, addressing the growth of a tumor cell, the evolution of a urban system over a long period, and the spatial repartition of urban population in Bogotá. Then we generalize the underlying agent-based architectures in order to illustrate the possibility of application on other modeling questions.