wald.nls2(nls2.object, file, pbispsi=c(nls2.object$model$gamf, nls2.object$model$gamv), varpsi=NULL)
VALUE:
a list with the following components:
"psi": the values of the functions.
A vector of length equal either to the number of values
of the argument `varpsi', or to the number of functions.
"d.psi": the derivatives of the functions with respect to the
active parameters introduced by
the `ppsi' declaration in the formal description-file.
A matrix whose number of rows is equal to the length of the "psi" component
and number of columns is equal to the length of the
`ppsi' declaration of the formal description-file.
"std.error": the standard error of the functions values.
"var.psi": the variance of the functions.
"statistic": the value of the Wald statistic.
CONSTRAINTS:
In the input argument `nls2.object', component `as.var' should exist.
The function `loadnls2', argument `psi' not NULL,
should have been previously called.
SIDE EFFECTS:
If no program has been previously loaded to calculate the functions
(see `loadnls2'),
an operating-system file is created which contains the C-program
that corresponds to the formal description of the functions.
If this file already exists, it is replaced.
DETAILS:
This function is a method for the generic function `wald'
for class `nls2'.
It can be invoked by calling `wald' for an object of the appropriate
class, or directly by calling `wald.nls2' regardless of the
class of the object.
NOTE:
The Wald statistic is calculated by inverting a matrix that may be
singular; in that case, a warning is issued.
SEE ALSO:
Example1 CORTISOL: The description-file, named "modelpsi", is the following: psi f1; ppsi g; aux a1; subroutine; begin a1=exp(2*log(g)); f1=if a1 < 0.00001 then 100 else 1/g fi; end
The commands of the S-session are: loadnls2(psi="") wald.out_ wald(nls2.out, "modelpsi")
Example2 CORTISOL: For testing "g=1, h=0", the description-file, named "mod", is: psi fg, fh; ppsi g, h; subroutine; begin fg = g -1; fh = h; end
The commands of the S-session are: loadnls2(psi="") wald.out_wald(nls2.out, "mod")