Sepia : semantic parsing for named entities
Gregory A. Marton · 2003
People's names, dates, locations, organizations, and various numeric expressions, col-lectivelv called Named Entities, are used to convey specific meanings to humans in the same way that identifiers and constants convey meaning to a computer language interpreter. Natural Language Question Answering can benefit from understanding the meaning of these expressions because answers in a text are often phrased dif-ferently from questions and from each other. For example, "9/11 " might mean the same as "September 11th " and "Mayor Rudy Giuliani " might be the same person as "Rudolph Giuliani". Sepia, the system presented here, uses a lexicon of lambda expressions and a mildly context-sensitive parser ri ireateA data structure fe ehch ' named entity. The parser and grammar design are inspired by Combinatory Categorial Grammar. The data structures are designed to capture semantic dependencies using common syntactic forms. Sepia differs from other natural language parsers in that it does not use a pipeline architecture. As yet there is no statistical component in the architecture.