1. A method, comprising: providing for establishing a model W for emulating a physical quantity P which depends on at least one input parameter x, defining a set X comprising N distinct parameter values x_i for said at least one input parameter x, N being an integer greater than or equal to 1, first measuring the physical quantity Pm 1 for each of the N distinct parameter values x_i of the at least one input parameter x, while keeping all other input parameters fixed, constructing a Vandermonde matrix VM using said set of N parameter values x_i of said at least one input parameter x, and computing the model W for emulating the physical quantity PE based on the Vandermonde matrix and the first measured physical quantity according to the equation W=(VM T *VM) −1 *VM T *Pm 1 .