------------------------------------------------------ URA 2055 ---------------- Author(s) : THIOULOUSE J.,CHESSEL D. Les analyses multitableaux en ecologie factorielle . I : de la typologie d'etat a la typologie de fonctionnement par l'analyse triadique Acta Oecologica - Oecologia Generalis Serial Number : 8, 1987, pp. 463-480 ISSN : 0243-766X Key-Words : PHYSICO-CHEMICAL VARIABLES,SPATIAL-TEMPORAL STRUCTURES,MULTI-TABLE ANALYSIS,TRIADIC ANALYSIS,PRINCIPAL COMPONENT ANALYSIS Abstract Triadic analysis is well adapted to the statistical study of multivariate surveys that are collected more than once. Triadic analysis is a particular case of the so-called "multi-table analyses", and therefore benefits from the descriptive power of the underlying theoretical tools of these methods. The interstructure proposes an ordination of the sampling dates and an overall typology of spatial processes. The compromise expresses the structures common to each date, from both the viewpoints of variables and sampling sites. The infrastructure offers a detailed description of deviations from the common model of the compromise for each date. The method proposed here leads to many generalizations concerning this kind of analysis. We present a simple computational procedure, using only principal components analysis. E-Mail : thioulou@biomserv.univ-lyon1.fr Laboratoire de Biometrie, Genetique et Biologie des Populations (URA 2055) - Univ. C. Bernard LYON I - 69622 VILLEURBANNE CEDEX