出版社：Consejo Superior de Investigaciones Científicas
摘要：A bibliographical search in the databases ERIC, LISA and ISA of the DIALOG host, during the period January 1995 lo June 1997, requiring that the term «information retrieval» appeared in the title has heen carried out. The objectives are to study the characteristics and factors related lo the coverage, update and indexation of the databases, as well as to determine the most frequent research topics and the cost-benefit of the databases. In the results of the evaluation, a common and negative characteristic of the three databases is the considerable time delay in their update. In relation lo the indexation, LISA lacks specificity and exhaustivity in the index terms, although it is the one that covers a larger number of journals and documents. Due to the existence of non pertinent references, it can turn out to be the most expensive database. ERIC stands as being economic, with a high degree of speciflcity, exhaustivity and precision in the indexation; however it covers few joumals although they are the most important. ISA is an accurate database with an important coverage and exact and exhaustive indexation, but it is the most expensive of them all.
关键词：information retrieval;evaluation;online databases;LISA;ERIC;ISA;recuperación de la información;evaluación;bases de datos online;LISA;ERIC;ISA
