A new measure of symmetry and its application to classification of bifurcating structures

This paper presents a new measure of symmetry for bifurcating structures, which relies not only on topology and ordering, but also on quantitative properties (e.g. length of branches). This measure is based on a specific biological mechanism and on the concept of minimum energy. The effectiveness of the approach is demonstrated in a classification test where leaves taken from plants growing under different stress conditions are classified. Results show that the proposed measure improves classification performance compared to classification based on other leading measures. 2007 Pattern Recognition Society. Published by Elsevier Ltd. All rights reserved.