Spider

The access structure, the retrieval model, and the system architecture of the SPIDER information retrieval system are described. The access structure provides efficient weighted retrieval on dynamic data collections. It is based on signatures and non-inverted item descriptions. The signatures provide upper bounds for the exact retrieval status values such that only a small number of exact retrieval status values have to be computed. SPIDER's retrieval model is a probabilistic retrieval model that is capable to exploit the database scheme of semistructured data collections. This model can be considred as a further development of the Binary Independence Indexing (BII) model. The system architecture was derived systematically from a given set of requirements such as effective and efficient retrieval on dynamic data collections, exploitation of the database scheme, computed views, and the integration of information retrieval functionality and database functionality.