A system for calculating the importance of web pages is provided. The web pages are organized hierarchically into collections. The system calculates the importance of each collection based on inter-collection links from a web page in one collection to a web page in another collection. The system then calculates the importance of web pages in the collections with a high calculated importance based on links between the web pages in those collections using, for example, a conventional page rank algorithm. The system may also calculate the importance of web pages in each collection with a low calculated importance separately based on the links between the web pages in the collection using, for example, a conventional page rank algorithm.