To determine changes in soft tissue profile in patients with Class II division 1 malocclusions treated with Twin Block appliances (TBA), 99 pairs of lateral cephalographs were traced and 25 soft tissue landmarks digitized. Procrustes superimposition was used to generate average soft tissue profiles scaled to an equivalent size. Statistical differences between prepubertal, pre- and post-treatmen...

OBJECTIVES This study aimed to quantify the patterns of shape variability and the extent and patterns of shape covariation between the upper and lower dental arch in an orthodontic population. METHODS Dental casts of 133 white subjects (61 males, 72 females; ages 10.6-26.6) were scanned and digitized in three dimensions. Landmarks were placed on the incisal margins and on the cusps of canines...

We present Procrustean Approach to Cophylogeny (PACo), a novel statistical tool to test for congruence between phylogenetic trees, or between phylogenetic distance matrices of associated taxa. Unlike previous tests, PACo evaluates the dependence of one phylogeny upon the other. This makes it especially appropriate to test the classical coevolutionary model that assumes that parasites that spend...

In this paper, we consider the non-symmetric positive semidefinite Procrustes (NSPSDP) problem: Given two matrices X,B∈Rn,m, find matrix A∈Rn,n that minimizes Frobenius norm of AX−B and which is such A+AT semidefinite. We generalize semi-analytical approach for symmetric problem, where A required to be semidefinite, was proposed by Gillis Sharma (A Linear Algebra Appl. 540, 112-137, 2018). As c...

Introduction: Diffusion tensor imaging (DTI) is becoming increasingly important in clinical studies of diseases such as multiple sclerosis and schizophrenia, and also in investigating brain connectivity. Hence, there is a growing need to process diffusion tensor (DT) images within a statistical framework based on appropriate mathematical metrics. However, the usual Euclidean operations are ofte...