Minpack includes software for solving nonlinear equations and nonlinear least squares problems.

MINPACK includes software for solving nonlinear equations and nonlinear least squares problems.

Non-linear least squares Non-linear least squares is the form of least squares analysis used to fit a set of "m" observations with a model that is non-linear in "n" unknown parameters ("m" > "n").

The Gauss–Newton algorithm is a method used to solve non-linear least squares problems.

Non-linear least squares problems arise, for instance, in non-linear regression, where parameters in a model are sought such that the model is in good agreement with available observations.

The STATGRAPHICS Nonlinear Least Squares procedure uses an algorithm due to Marquardt to fit any function entered by the user.

In that case we have to use nonlinear minimization techniques (see Appendix).

I was then able to graph the data, take numerical derivatives, and calculate nonlinear least-square curve fits to obtain the desired results.

The parameters are initialized using estimates from 10-year rolling regressions using nonlinear least squares, subject to the same constraints described above and with the NAIRU assumed to be fixed in each rolling window.