Interactive browser for Tracing Minimization

DESCRIPTION:

A tracing function that can be used while fitting a nonliniar model by minimum sums (the ms function).

USAGE:

browser.ms(info, theta, grad, scale, flags, fit.pars) 

This function can be supplied as the value of the trace= argument to function ms. The effect will be to put you into an interactive browser in a frame containing all the information available about the current stage of the iteration. The first argument is split out into the following variables: niter, nfun, fvalue, tracelevel, deltaf, pred.deltaf, rel.detatheta, step.scale, d*step.scale. The last two arguments are the integer and numeric working arrays of the Fortran algorithm underlying ms.
Use of the interactive browser on every iteration is only advisable in cases where very detailed convergence behavior has to be understood. In other circumstances, the trace option is the better choice.

NOTE:

By a historical slip (that is, it got into the book that way), this function has the name of a method for browser for ms objects. It detects this case and acts appropriately, but it really ought to have a different name, say trace.ms.browser.

SEE ALSO:

, .

EXAMPLES:

ms(~myobj(x, theta), data = my.pframe, trace = browser.ms)