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Shape averages and their Bias

Part of: Multivariate analysis

Published online by Cambridge University Press:  01 July 2016

K. V. Mardia  and
I. L. Dryden
K. V. Mardia
Affiliation:
University of Leeds
I. L. Dryden*
Affiliation:
University of Leeds
*
* Postal address: Department of Statistics, University of Leeds, Leeds, LS2 9JT, UK
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Abstract

The paper considers the bias of Bookstein's mean estimator for shape under the isotropic normal model. This work depends on certain distributional properties of shape variables. An alternative unbiased modified estimator is proposed and its performance is compared with various estimators, including Procrustes and the exact maximum likelihood estimator, in a simulation study.

Keywords

LANDMARKSPROCRUSTESSHAPESIZETRIANGLE

MSC classification

Primary: 62H11: Directional data; spatial statistics
Type
General Applied Probability
Information
Advances in Applied Probability , Volume 26 , Issue 2 , June 1994 , pp. 334 - 340
Copyright
Copyright © Applied Probability Trust 1994 

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