Intelligent information agents: Review and challenges for distributed information sources

Inexperienced users typically obtain one of three possible outcomes when they search for online information: They are buried under an information avalanche, they are unable to locate any useful information at all, or they find what they need in roughly the amount they need. Unfortunately, the latter outcome is the most rare. Unfamiliarity with search tactics creates difficulties for many users of online retrieval systems. When faced with poor results, even experienced searchers may use vocabulary incorrectly and often fail to reformulate their queries. Far from being the answer to everyone's information dreams, distributed sources of online information, i.e., the World Wide Web (WWW), compound the problem and may often turn into an information nightmare. To address this problem, intelligent online search assistants, or agents, are being developed for information retrieval applications. There are many approaches, both theoretical and implemented, to using intelligent software agents for information retrieval purposes. These approaches range from desktop agents specialized for a single user to networks of agents used to collect data from distributed information sources, including Web sites. This article presents an overview of intelligent software agents in information retrieval, including an explanation of agents and agent architectures, and presents several agent systems. We distinguish between agents as individual entities, whose properties and characteristics we describe separately, and agent systems as collections of agents utilized for information retrieval tasks, which we discuss in terms of individual implementations. © 1998 John Wiley & Sons, Inc.