Selecting scales by multiple kernel learning for shape diffusion analysis

Autor: Castellani, Umberto, Ulas, Aydin, Murino, Vittorio, Bellani, Marcella, Rambaldelli, Gianluca, Tansella, Michele, Brambilla, Paolo
Přispěvatelé: Department of Computer Science [Verona] (UNIVR | DI), University of Verona (UNIVR), Italian Institute of Technology (IIT), Department of Diagnostics and Public Health [Verona] (UNIVR | DDSP), Inter-University Centre for Behavioural Neurosciences (ICBN), Università degli Studi di Udine - University of Udine [Italie]-University of Verona (UNIVR), Pennec, Xavier and Joshi, Sarang and Nielsen, Mads, Session : Poster, Pennec, Xavier, Pennec, Xavier and Joshi, Sarang and Nielsen, Mads
Jazyk: angličtina
Rok vydání: 2011
Předmět:
Zdroj: Proceedings of the Third International Workshop on Mathematical Foundations of Computational Anatomy-Geometrical and Statistical Methods for Modelling Biological Shape Variability
Proceedings of the Third International Workshop on Mathematical Foundations of Computational Anatomy-Geometrical and Statistical Methods for Modelling Biological Shape Variability, Sep 2011, Toronto, Canada. pp.148-158
Popis: International audience; Brain morphological abnormalities can typically be detected by advanced geometrical shape analysis techniques. Recently, shape diffusion methods have proved to be very effective in providing useful descriptions for brain classification purposes. In particular, they allow the analysis of such shapes at multiple scales, but the selection of the correct range of scales remains an open issue heavily affecting the performance of methods, and it needs to be estimated adaptively for different classes of shapes. In this paper, we focus on the diffusion scale selection in order to define a robust shape descriptor for brain classification. To this end, geometric features are extracted for each scale and the best feature combination is selected by employing \it multiple kernel learning (MKL). In the presented experiments, we compare the shape of Thalamic regions in order to discriminate between normal subjects and schizophrenic patients. We demonstrate that MKL allows to obtain classifiers which are more accurate with respect to other competing algorithms for schizophrenia detection. Moreover, using the weights computed by the MKL algorithm, we can select at which scale the features are more effective for schizophrenia classification.
Databáze: OpenAIRE