Bringing Your Dead Links Back to Life: A Comprehensive Approach and Lessons Learned

This paper presents an experimental study of the automatic correction of broken (dead) Web links focusing, in particular, on links broken by the relocation of Web pages. Our first contribution is that we developed an algorithm that incorporates a comprehensive set of heuristics, some of which are novel, in a single unified framework. The second contribution is that we conducted a relatively large-scale experiment, and analysis of our results revealed the characteristics of the problem of finding moved Web pages. We demonstrated empirically that the problem of searching for moved pages is different from typical information retrieval problems. First, it is impossible to identify the final destination until the page is moved, so the index-server approach is not necessarily effective. Secondly, there is a large bias about where the new address is likely to be and crawler-based solutions can be effectively implemented, avoiding the need to search the entire Web. We analyzed the experimental results in detail to show how important each heuristic is in real Web settings, and conducted statistical analyses to show that our algorithm succeeds in correctly finding new links for more than 70% of broken links at 95% confidence level.