In the ROC algorithm, instead of a number z which designs the threshold above which a cell characterized by continuous variable Z (for example its mean Rn potential RP) belongs into U0, otherwise into U1, we now use the index b, which is the value of the binary sequence (g(k), …, g(1)). By varying b from 0 to 2k 1, all possibilities of sorting of the classes into U0 and U1, are included.