Missing web pages (pages that return the 404 "Page Not Found" error) are part
of the browsing experience. The manual use of search engines to rediscover
missing pages can be frustrating and unsuccessful. We compare four automated
methods for rediscovering web pages. We extract the page's title, generate the
page's lexical signature (LS), obtain the page's tags from the bookmarking
website delicious.com and generate a LS from the page's link neighborhood. We
use the output of all methods to query Internet search engines and analyze
their retrieval performance.