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On the consistency of procrustean mean shapes

Published online by Cambridge University Press:  01 July 2016

Huiling Le*
Affiliation:
University of Nottingham
*
Postal address: Department of Mathematics, University of Nottingham, University Park, Nottingham NG7 2RD, UK.

Abstract

We discuss the uniqueness of the Fréchet mean of a class of distributions on the shape space of k labelled points in ℝ2, the supports of which could be the entire space. From this it follows that the shape of the means is the unique Fréchet mean shape of the induced distribution with respect to an appropriate metric structure, provided the distribution of k labelled points in ℝ2 is isotropic and satisfies a further mild condition. This result implies that an increasing sequence of procrustean mean shapes defined in either of the two ways used in practice will tend almost surely to the shape of the means.

Type
Stochatic Geometry and Statistical Applications
Copyright
Copyright © Applied Probability Trust 1998 

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