  Several real problems ranging from text classification to computational
biology are characterized by hierarchical multi-label classification tasks.
Most of the methods presented in literature focused on tree-structured
taxonomies, but only few on taxonomies structured according to a Directed
Acyclic Graph (DAG). In this contribution novel classification ensemble
algorithms for DAG-structured taxonomies are introduced. In particular
Hierarchical Top-Down (HTD-DAG) and True Path Rule (TPR-DAG) for DAGs are
presented and discussed.
