Dominance Constraints With Boolean Connectives: A Model-Eliminative Treatment

Author: Denys Duchier

Editor:

Dominance constraints are a language of tree descriptions. Tree descriptions are widely used in computational linguistics for talking and reasoning about trees. While previous research has focused on the conjunctive fragment, we now extend the account to all Boolean connectives and propose a new formalism that combines dominance constraints with a feature tree logic. Although the satisfiability problem in the conjunctive fragment is known to be NP-complete, we have previously demonstrated that it can be addressed very effectively by constraint propagation: we developed an encoding that transforms a dominance constraint into a constraint satisfaction problem on finite sets solvable by constraint programming. We present a generalization of this encoding for our more expressive formalism, and prove soundness and completeness. Our main contribution is a treatment of disjunction suitable for constraint propagation.