Canonical non-symmetrical correspondence analysis is developed as an alternative method for constrained ordination, relating external information (e.g., environmental variables) with ecological data, considering species abundance as dependant on sites. Ordination axes are restricted to be linear
combinations of the environmental variables, based on the information of the most abundant species. This extension and its associated unconstrained ordination method are terms of a global model that permits an empirical evaluation of the impact that the environmental variables have on the community
composition. Scores, contributions, qualities of representation, interpretation of dispersion graphs and an application to real vegetation data are presented.
CitacióWillems, P. M.; Galindo Villardon, Ma. Purificación. Canonical non-symmetrical correspondence analysis: an alternative in constrained ordination. "SORT", 2008, vol. 32, núm. 1, p. 93-112.