where wp is a weight coefficient that characterizes the relative contribution of the
information of the original function at the point p, p=1,...,P.
The construction of response surface models is an iterative process. Once an
approximate model is obtained, the goodness-of-fit determines if the solution is
satisfactory. If this is not the case, the approximation process is restarted and further
experiments are made or the GP model is evolved with different parameters, as
explained in Chapter 4.