Instead of computing the parameters using a mathematical program, as is often done, aiming to minimize the discrepancies between the answers to the precise questions and the values of the function k, we opted, following the insight that models and theories rest in part on intuition, for a manual approach where the decision theorists and the expert discussed the values and the reasoning behind them. As an illustration of the value of this approach, we asked again some of the questions where we suspected that the expert had given an answer that was not in line with his own reasoning, and indeed this permitted the expert to correct some of his previous answers (Supplementary Section 1). Another important guide to our approach was to reduce the number of parameters. That is due to the limitation on the number of questions that an expert can answer, and because of the limitation that should realistically be considered about expert knowledge, especially in zones of scales that he is not familiar with.