existsPIC-methods: Methods for Function existsPIC in Package `distrMod'
Description
existsPIC-methods to check whether in a given L2 differentiable model at parameter value theta there exist
(partial) influence curves to Trafo $D_theta$.Usage
existsPIC(object, ...)
"existsPIC"(object, warning = TRUE, tol = .Machine$double.eps)
Arguments
...
further arguments used by specific methods.
warning
logical: should a warning be issued if there exist no (partial) influence curves?
tol
the tolerance the linear algebraic operations. Default is .Machine$double.eps.
Details
To check the existence of (partial) influence curves and, simultaneously, for bounded
(partial) influence curves, by Lemma 1.1.3 in Kohl(2005) [resp. the fact that $ker I = ker J$
for $J= E (Lambda',1)' (Lambda',1) w$ and
$w=min(1, b/|(Lambda',1)|)$], it suffices to check that
$ker I$ is a subset of $ker D_theta$. This is done by
a call to isKerAinKerB.References
Kohl, M. (2005) Numerical Contributions to the Asymptotic Theory of Robustness.
Bayreuth: Dissertation.