Information retrieval (IR) deals with the representation, storage organization of, and access to information items. The representation and organization of the information items should provide the user with easy access to the information in which he is interested. Unfortunately, characterization of the acer information need is not a simple problem. Consider, for instance, the following hypothetical user information need in the context of the World Wide Web (or just the Web): Find all the pages (documents) containing information on college ten-His teams which:
(1) are maintained by an university in the USA and (2) participate in the NCAA tennis tournament. To be relevant, the page must include information on the national ranking of the team in the last three years and the email or phone number of the team coach.
Clearly, this full description of the user information need cannot be used directly to request information using the current interfaces of Web search engines. Ins tead, the user must first translate this information need into a queqj which can be proceed by the search engine (or IR system). in its most common form, this translation yields a set of keywords (or index terms) which summarizes the description of the user information need. Given the user query, the key goal of an IR system is to retrieve information which might be useful or relevant to the user. The emphasis is on the retrievai of information as opposed to the retrieval of data,
Clearly, this full description of the user information need cannot be used directly to request information using the current interfaces of Web search engines. Ins tead, the user must first translate this information need into a queqj which can be proceed by the search engine (or IR system). in its most common form, this translation yields a set of keywords (or index terms) which summarizes the description of the user information need. Given the user query, the key goal of an IR system is to retrieve information which might be useful or relevant to the user. The emphasis is on the retrievai of information as opposed to the retrieval of data,
