English

Addendum to the discussion of "Breakdown and groups"

Statistics Theory 2007-06-13 v2 Statistics Theory

Abstract

In his discussion of Davies and Gather [Ann. Statist. 33 (2005) 977--1035] [math.ST/0508497] Tyler pointed out that the theory developed there could not be applied to the case of directional data. He related the breakdown of directional functionals to the problem of definability. In this addendum we provide a concept of breakdown defined in terms of definability and not in terms of bias. If a group of finite order kk acts on the sample space we show that the breakdown point can be bounded above by (k1)/k(k-1)/k. In the case of directional data there is a group of order k=2k=2 giving an upper bound of 1/2.

Keywords

Cite

@article{arxiv.math/0507089,
  title  = {Addendum to the discussion of "Breakdown and groups"},
  author = {P. Laurie Davies and Ursula Gather},
  journal= {arXiv preprint arXiv:math/0507089},
  year   = {2007}
}

Comments

Published at http://dx.doi.org/10.1214/009053606000000399 in the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org)

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