Measuring the extension of the F.T.P.
It is obvious that, for a given subject, the number of his future periods depends on his age (see Fig. 2). Our problem, now, is to measure the distance between the subject's present time and the time periods in which his motivational objects are localized. These distances are the basic for measuring the extension of his F. T.P. as a whole. Several methods will be proposed successively: the F. T.P. profile, the F.T.P. index, the median rank of F.T.P., and the mean F.T.p.-extension score. For the meaning of some symbols used in this chapter see the Manual of F. T.P. analysis.