Comparing DIALOG, TARGET, and DR-LINK

摘要

Ideally, an information retrieval system should be an answer machine. It should interpret the questions we ask in plain English and return not only what we asked for, but what we meant to ask for. It must understand not just single words, but the sum of what those words mean, which is often different. We shouldn't have to play clever games in order to get the answers we need. Nor should we have to learn secret codes, or remember which field is phrase indexed, or go hunting for five variants of a journal title or an author's name. We should be able to go into the information store, see what they have, and buy some answers.