curve
curve
Description
Curvature calculations and summary statistics as in Bates and Watts.
Usage
curve(func, x, signif = 0.05, show.details = F, track=F)
curve(Dlist, signif = 0.05, show.details = F, track=F)
Required Arguments
The function is generic. It can be called with a function and parameter matrix,
in which case the Bates and Watts D matrix is calculated, or with a previously
calculated D matrix.
- func, x,
-
func is a function which returns a sample space vector at the parameter value x.
- Dlist
-
Dlist is a list as generated by genD,
with the 3 elements as follows:
$D is a matrix of first(gradients) and second order partial
derivatives organized in the same manner as Bates and
Watts. (first p columns are the gradients and the
next p(p-1)/2 columns are the lower triangle of the Hessian).
$p is the dimension of the parameter space=dim of the tangent space.
$f0 is the function value at the point where the matrix D
was calculated. (The calculation should not/does not? depend on
this value - but it should be the right dimension and 0's do
not work.
Optional Arguments
- signif
-
The significance level to
- show.details
-
If show.details=T then intermediate calculations are printed.
- track
-
If track=T then the progress of the calculations is printed.
Value
A list is returned (with invisible). Curvature summary statistics as in Bates and Watts are in the element $stat. A representation of the Bates and Watts D matrix is in the element $Dlist. The curvature array C as in Batts and Watts defn. (7.16) p242 and examples p244 & p245 is in the elements $C.parameter and
$C.intrinsic.
Side Effects
Curvature summary statistics as in Bates and Watts are printed.
REFERENCES
See Bates and Watts(1983), 'Nonlinear Regression Analysis and Its Applications.'
See Also
Examples
curve(genD(estmodel)) # find a better example !!
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