A method for comparative analysis of structural complexity in bi- and trifurcating tree-like structures

To classify and statistically compare architecture data from biand trifurcating tree-like structures across different sizes the Tree Symmetry Index as the mean of an asymmetry measure at all the branching points in the centrifugal hierarchy as developed by Van Pelt et al. (1992) and Van Pelt (1997) or the branching points mean in centrifugal hierarchy developed by Sismilich (2001) and Sismilich et al. (2003). Some of the comparative methods described earlier show instability for certain sizes of tree-like structures. We present simulation examples of instability. A new method will be described, and simulations showing how greater stability and discriminative power can be achieved with this new method for comparative analysis. Moreover, we will show that more information of the structural complexity by the new method downscaled parameters are upheld.