Searching the World Wide Web (1998) - Lawrence, Giles Abstract: The coverage and recency of the major World Wide Web search engines was analyzed, yielding some surprising results. The coverage of any one engine is significantly limited: No single engine indexes more than about one-third of the ªindexable Web,º the coverage of the six engines investigated varies by an order of magnitude, and combining the results of the six engines yields about 3.5 times as many documents on average as compared with the results from only one engine. Analysis of the overlap between pairs of engines gives an estimated lower bound on the size of the indexable Web of 320 million pages. By NemSysin AI for PhD > 1. Search Engine Designwith _enginesgileslawrencesearch