PASCAL - Pattern Analysis, Statistical Modelling and Computational Learning

Graph kernels based on tree patterns for molecules
Pierre Mahé and Jean-Philippe Vert
Machine Learning Volume 75, Number 1, pp. 3-35, 2009.


Motivated by chemical applications, we revisit and extend a family of positive definite kernels for graphs based on the detection of common subtrees, initially proposed by Ramon and Gärtner (Proceedings of the first international workshop on mining graphs, trees and sequences, pp. 65–74, 2003). We propose new kernels with a parameter to control the complexity of the subtrees used as features to represent the graphs. This parameter allows to smoothly interpolate between classical graph kernels based on the count of common walks, on the one hand, and kernels that emphasize the detection of large common subtrees, on the other hand. We also propose two modular extensions to this formulation. The first extension increases the number of subtrees that define the feature space, and the second one removes noisy features from the graph representations. We validate experimentally these new kernels on problems of toxicity and anti-cancer activity prediction for small molecules with support vector machines.

EPrint Type:Article
Project Keyword:Project Keyword UNSPECIFIED
Subjects:Learning/Statistics & Optimisation
Theory & Algorithms
ID Code:4432
Deposited By:Jean-Philippe Vert
Deposited On:13 March 2009