Alessandro Ferrarini Computational Ecology and Software 2220-721X 2012 2 213-219 12/2012 International Academy of Ecology and Environmental Sciences competing alternatives decision making sensitivity analysis TOPSIS-like algorithm user-defined decision function what-if analysis Ecological ranking and environmental decision making require that a set of objects (e.g., competing sites for species introduction, or alternative sites for the allocation of man-made features) are listed from the best to the worst one. The resulting ranking is then used to choose which actions to implement; worse and intermediate solutions are immediately excluded, while optimal and sub-optimal solutions are taken into account, discussed and then applied. In this paper, WORTHY is presented as a new model for ecological ranking and evaluation of competing alternatives based on a set of weighted criteria. I have developed WORTHY model with the goal of employing a TOPSIS-like algorithm for worthy solutions in situations of environmental and ecological conflict management. Compared to TOPSIS algorithm, WORTHY allows to: a) decide the type of normalization, b) build an user-defined decision function, c) perform what-if analysis and d) sensitivity analysis. DOI 10.0000/issn-2220-721x-compuecol-2012-v2-0016 http://www.iaees.org/publications/journals/ces/articles/2012-2(4)/a-new-model-for-ecological-ranking-and-evaluation.pdf