Strange behavior with Nonlinear regress
- To: mathgroup at smc.vnet.net
- Subject: [mg40876] Strange behavior with Nonlinear regress
- From: "Nathan Moore" <nmoore at physics.umn.edu>
- Date: Tue, 22 Apr 2003 06:50:20 -0400 (EDT)
- Organization: University of Minnesota, Physics
- References: <b70npo$9gd$1@smc.vnet.net> <200304100736.DAA24158@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Having trouble with nonlinear regress function tonight. I have a data set
that I'd like to fit an exapansion to. When I use nonlinear regress to fit
the parameters they all diverge to non-physical quantities. The help menu
seems to infer that it is possible to specif bounds for the fitting
parameters, but when I do so the program seems to find a fit with solution
outside the interval I've specified.. An example of this,
have data set of {x,y} points.
correctedtr;
then try to fit the data,
NonlinearRegress[correctedtr, n^(2 nu)/a, n, {{a, 10, 0, 20}, {nu,
0.4, 0.3, 0.5}}]
assuming here that a should be found on the interval [0,20], nu on the
interval [0.3,0.5]
output in real life is,
BestFitParameters{a->29.2876,nu->0.583367},
what's going on?????? what are the parametrs outside the bounds I specify?
I'd love to know
NT Moore
- References:
- Re: sum with lists
- From: bobhanlon@aol.com (Bob Hanlon)
- Re: sum with lists