Acquisition of semantic patterns for information extraction from corpora

A knowledge acquisition tool to extract semantic patterns for a memory-based information retrieval system is presented. The major goal of this tool is to facilitate the construction of a large knowledge base of semantic patterns. The system acquires semantic patterns from texts with a small amount of user interaction. It acquires new phrasal patterns from the input text, maps each element of the pattern to a meaning frame, generalizes the acquired pattern, and merges it into the current knowledge base. Interaction with the user is introduced at some decision points, where the ambiguity cannot be resolved automatically without other pieces of predefined knowledge. The acquisition process is described in detail, and a preliminary experimental result is discussed