Data from search engine analysis run on Jan. 5, 1999

Based on an analysis of the same four very small searches used for the overlap analysis, the following table shows the number of total hits and the number and percent of dead links from those total hits for each search engine. Dead links were those URLs that resulted in a 404 error message (file not found) from the server. None of the unique hits were dead links, but to get the percentage of unique hits, the number of dead links were subtracted from the total hits.

This example is from a total of 173 hits from four searches found by ten search engines Of the 173 total hits, 83 were unique Web pages. Of those, 10 were dead links. All 10 were included in more than one search engine database.

While this sample is too small to make an accurate generalization, Google!, Excite, and HotBot had the lowest percentage of dead links. At the same time the HotBot's Inktomi database scores so well, two other Inktomi-based search engines fared the worst: MSN Web Search and Yahoo!'s search engine (not the directory part of Yahoo!, but the Inkomi part).

See also statistics on search engine size, the lack of overlap between the search engines, unique hits, and the change over time.