Text Information Retrieval Systems

Information retrieval is a communication process that links the information user to a librarian, museum curator, fingerprint identification specialist, or whoever is in charge of a collection of what we are calling documents. The communication will normally involve the processing of text, strings of words known to both parties in the process that can be used to describe a document's content and other attributes and link it with a need expressed in similar terms. This book's purpose is to teach people who will be searching or designing text retrieval systems how the systems work. For designers, it covers problems they will face and reviews currently available solutions to provide a basis for more advanced study. For the searcher its purpose is to describe why such systems work as they do. The book is primarily about computer-based retrieval systems, but the principles apply to nonmechanized ones as well. The book covers the nature of information, how it is organized for use by a computer, how search functions are carried out, and some of the theory underlying these functions.
As well, it discusses the interaction between user and system and how retrieved items, users, and complete systems are evaluated. A limited knowledge of mathematics and of computing is assumed. The first edition of this work appeared just before the World Wide Web came on the scene, but was nonetheless a student favorite because of its clarity. The new edition is updated and expanded, covering not only the Web but also new developments in how IR systems are or could be designed. It helps users understand why things happen the way they do and thus aids users in designing new systems, evaluating systems before use, and teaching or using IR systems. It provides an understanding of basic principles so that users may read, understand, and evaluate detailed works such as the many research papers on this topic. It explains complex mathematical models so that readers may become familiar with the underlying mathematical concepts of IR systems.