summary.nlmrt {nlmrt} | R Documentation |
Summary output for nlmrt object.
Description
Provide a summary output (but involving some serious computations!) of
an object of class nlmrt from nlxb
or nlfb
from package
nlmrt
.
Usage
## S3 method for class 'nlmrt'
summary(object, ...)
Arguments
object |
An object of class 'nlmrt' |
... |
Any data needed for the function. We do not know of any! |
Details
summary.nlmrt
performs a summary method for an object of class 'nlmrt' that
has been created by a routine such as nlfb
or nlxb
for nonlinear
least squares problems.
Issue: When there are bounded parameters, nls
returns a Standard Error for each of
the parameters. However, this summary does NOT have a Jacobian value (it is set to 0)
for columns where a parameter is masked or at (or very close to) a bound. See the
R
code for the determination of whether we are at a bound. In this case,
users may wish to look in the inst/dev-codes
directory of this package,
where there is a script seboundsnlmrtx.R
that computes the nls()
standard errors for comparison on a simple problem.
Issue: The printsum() of this object includes the singular values of the Jacobian. These are displayed, one per coefficient row, with the coefficients. However, the Jacobian singular values do NOT have a direct correspondence to the coefficients on whose display row they appear. It simply happens that there are as many Jacobian singular values as coefficients, and this is a convenient place to display them. The same issue applies to the gradient components.
Value
returns an invisible copy of the nlmrt object.
Note
Special notes, if any, will appear here.
Author(s)
John C Nash <nashjc@uottawa.ca>
See Also
Function nls()
, packages optim
and optimx
.