Graph-based representation and techniques for NLU application development

Abstract

We describe a method to represent, manipulate, structure and aid in the design and development of NLU oriented parsers. Our method is based on the representation of the semantic parser domain into a single directed graph showing the parser's labels and their immediate inter-relationships as they exist in the annotated development corpora. Furthermore, we present methods developed around this representation illustrating how, a developer can visualize, manipulate, design and construct new applications simply by acting on the domain graph and sub-graphs. We also describe how the graph representation method can be utilized in the reduction of the complexity of the parser by identification and removal of nodes, edges and structures of the domain graph whose impact on attribute accuracy is small. We present the following examples of applications of our technique: extension of an existing air travel information domain to include car rental reservation by manipulating the corresponding graphs, structuring such graphs' vertices into 3-tiers, an example of a method for complex domain decomposition into simpler sub-graphs, and experiments on the reduction of a parser's complexity. Our technique can serve as a foundation of GUI toolkits for NLU development built around these concepts.