Subject gateway sites and search engine ranking

The spread of subject gateway sites can have an impact on the other major Web information retrieval tool: the commercial search engine. This is because gateway sites perturb the link structure of the Web, something used to rank matches in search engine results pages. The success of Google means that its PageRank algorithm for ranking the importance of Web pages is an object of particular interest, and it is one of the few published ranking algorithms. Although highly mathematical, PageRank admits a simple underlying explanation that allows an analysis of its impact on Web spaces. It is shown that under certain stated assumptions gateway sites can actually decrease the PageRank of their targets. Suggestions are made for gateway site designers and other Web authors to