Summary: We introduce a new notion of logic equivalence based on a parametric family of fuzzy operators. This equivalence operator has helped us to define a new dissimilarity index for fuzzy sets. Our index is the fuzzy counterpart of a series of distances commonly used in data analysis and in particular the cardinal distance of the symmetric difference. From what follows, we use this dissimilarity to define a new efficiency indicator for a transport system. This has been made possible with the use of fuzzy uncoupling and its interpretation in terms of fuzzy logic connectives. We use these new tools on the data from an investigation that we carried out concerning the transportation of food stuff in Cameroon.