Tree Matching with Recursive Distributed Representations

We present an approach to the structure unification problem using distributed representations of hierarchical objects. Binary trees are encoded using the recursive auto-association method (RAAM), and a unification network is trained to perform the tree matching operation on the RAAM representations. It turns out that this restricted form of unification can be learned without hidden layers and producing good generalization if we allow the error signal from the unification task to modify both the unification network and the RAAM representations themselves. Paper to be presented at the Workshop on Integrating Neural and Symbolic Processes---the Cognitive Dimension at the National Conference on Artificial Intelligence, San Jose, CA, July 1992. y Computer Science Division, University of California at Berkeley, and International Computer Science Institute, 1947 Center St., Berkeley, CA 94704, stolcke@icsi.berkeley.edu. Research supported by an IBM Graduate Fellowship and by the Internati..