  We put forward a novel learning methodology for ensembles of decision trees
based on a genetic algorithm which is able to train a decision tree for
maximizing both its accuracy and its robustness to adversarial perturbations.
This learning algorithm internally leverages a complete formal verification
technique for robustness properties of decision trees based on abstract
interpretation, a well known static program analysis technique. We implemented
this genetic adversarial training algorithm in a tool called Meta-Silvae (MS)
and we experimentally evaluated it on some reference datasets used in
adversarial training. The experimental results show that MS is able to train
robust models that compete with and often improve on the current
state-of-the-art of adversarial training of decision trees while being much
more compact and therefore interpretable and efficient tree models.
