A double-frontier approach for measuring market imperfection

This paper proposes a new methodology for evaluating the market imperfection and the bargaining power of each agent acting on a given market. The new methodology is an extension of DEA to the two frontiers case with respect to a privileged direction. A particular attention is paid to the treatment of bidirectional free disposability. This model is motivated by the analysis of survey data consisting of a set of contracts described in the space of price and attributes.