This paper addresses an extension of an hierarchical covering location problem, in which the covers for the two levels of service are maximized independently. We present the mathematical model and seek an approximation for the efficient frontier of the corresponding bi-objective problem. The bi-objective model is solved by the weighting method, through a lagrangean heuristic. The computational results show that the solutions generated by this heuristic provide an approximation of the efficient frontier, including supported and non-supported efficient solutions.
multi-objective hierarchical location; lagrangean heuristic; efficient frontier
