The Role of Ambiguity in the Evaluation of the Net Benefits of the MOSE System in the Venice Lagoon

In this paper we apply the NEO-capacity framework to assess the role of ambiguity in a specific decision making problem. We first describe the framework and propose a graphical representation of the decision making functional. Then we apply it to a specific problem, namely, the role of ambiguity in the evaluation of the net benefits of the MOSE, the mobile barriers aimed to protect the Venice Lagoon from the periodic flooding (acqua alta). We show that the estimated impacts crucially depend on the level of optimism and pessimism of the decision maker and they substantially differ from the one calculated on the basis of the expected value. We also calculate the implicit ambiguity attitude of the decision maker.