Information Retrieval Transfer Cycle Dania Bilal IS 530 Fall 2007 Information Retrieval System A set of components that interact to provide feedback Comprised of interlinked entities Agency that creates the databases People Documents Interlinked Entities Agency People Documents IR Information Transfer Inputs Processes Objectives of the System Outputs The IR Cycle Documents are analyzed translated indexed and stored Documents are organized Cataloging description representation of docs Subject indexing The IR Cycle Subject indexing a Determination of subject content conceptual analysis b Translation of content into language of the system controlled vocabulary c Abstracting The IR Cycle Language of the system controlled vocabulary List of subject headings Pre coordinate Thesauri Pre coordinate Classification scheme The IR Cycle Documents are represented by other entities Author s Date of publication Language Identifiers Entities may become access points The IR Cycle Documents are stored after indexing Document representation is entered into the matching mechanism A file of document surrogates is established File becomes available for searching using a variety of entities access points The IR Cycle User Query Analyzed for conceptual content Translated into the language of the system matched against controlled vocabulary and keywords Matched against document surrogates in the database The IR Cycle Output A set of records found and deemed relevant to a user query User judgment of retrieval User Judgment Relevance to information need Relevance ranking by IR system Relevance vs pertinence Document Based IRs Input output and matching mechanisms Selection of documents done by indexers Analysis of documents done by indexers Document organization and representation done by indexers Document Based IRs Analysis of user query done by system Match of user query with relevant documents Delivery of documents output The IR Cycle Information Seeking Process of finding information to fill a knowledge gap User requests Known item searches Unknown item searches Subject searches Discussion How does the IR transfer cycle in databases varies from the cycle in Web search engines Search Logic Overview Boolean logic Search parameters Phrase Proximity Use of specific fields to search Nesting