Tendencias en los sistemas de indización automática. Estudio evolutivo

We present the evolution of the automatic and computer-assisted indexing systems since the first research began at the end of the fifties, until now. The systems described have been divided into four sections: 1) those that use non-linguistic methods, 2) employing linguistic criteria, 3) commercial systems, and 4) the latest trends in automatic indexing of multimedia information. To study this evolution we made a broad review of the literature covering four decades of research that have resulted in numerous projects of automatic or computer-aided indexation of which we shown more than twenty-five. Finally, we present some conclusions