UIC at TREC-2003: Robust Track

In TREC 2003, the Database and Information System Lab (DBIS) at University of Illinois at Chicago (UIC) participate in the robust track, which is a traditional ad hoc retrieval task. The emphasis is based on average effectiveness as well as individual topic effectiveness. Noun phrases in the query are identified and classified into 4 types: proper names, dictionary phrases, simple phrases and complex phrases. A document has a phrase if all content words in a phrase are within a window of a certain size. The window sizes for different types of phrases are different. We consider phrases to be more important than individual terms. As a consequence, documents in response to a query are ranked with matching phrases given a higher priority. WordNet is used to disambiguate word senses and bring in useful synonyms and hyponyms once the correct senses of the words in a query have been identified. The usual pseudo-feedback process is modified so that the documents are also ranked according to phrase and word similarities with phrase matching having a higher priority. Five runs which use either title or title and description have been submitted.