“…What researchers in fuzzy nonlinear regression were concerned with was data of the form with crisp inputs and fuzzy output. 3 Some papers, for example [1,2,5], were concerned with the data set with fuzzy inputs and fuzzy output. However, we think those fuzzy nonlinear regression methods look somewhat unrealistic and 5 treat the estimation procedures of some particular models such as linear, polynomial, exponential and logarithmic.…”