Retrieval
 Full text Indexing and Retrieval
Retrieval
l Unaided query, or assisted via
Natural language processing and query formulation
Search across multiple engines
Fuzzy search for OCR’d text and other typos
Term expansion via thesaurus, e.g. RUSSIA=USSR
l Summarization via
Hand-input abstracts
Relevance-ranked extracted sentences
Machine-assembled text
l Ranking via
Location and frequency of keywords  (AltaVista)
Site popularity or references   (Google)
Reviewer schemas   (Yahoo)