existsPIC-methods to check whether in a given L2 differentiable model at parameter value theta there exist (partial) influence curves to Trafo \(D_\theta\).
existsPIC(object, ...)
# S4 method for L2ParamFamily
existsPIC(object, warning = TRUE, tol = .Machine$double.eps^.5)
L2ParamFamily
further arguments used by specific methods.
logical: should a warning be issued if there exist no (partial) influence curves?
the tolerance the linear algebraic operations. Default is .Machine$double.eps^.5.
Peter Ruckdeschel peter.ruckdeschel@uni-oldenburg.de
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 \({\rm ker} I={\rm ker} J\)
for \(J= {\rm E} (\Lambda',1)' (\Lambda',1) w\) and
\(w={\rm min}(1, b/|(\Lambda',1)|\)], it suffices to check that
\({\rm ker }I\) is a subset of \({\rm ker }D_\theta\). This is done by
a call to isKerAinKerB.
Kohl, M. (2005) Numerical Contributions to the Asymptotic Theory of Robustness. Bayreuth: Dissertation.
isKerAinKerB