OPTIMIZING AN INDEX OF WEB DOCUMENTS

Historical usage data related to user queries and training properties for a plurality of web pages is received and utilized to train a mathematical model to predict the likelihood of retrieval of a web page during a web search. Properties are extracted from the plurality of web pages in the index and the mathematical model is applied to the properties for each web page to calculate a sortrank value. The index is reordered based on the sortrank value such that the web pages most likely to be retrieved by a user submitting a search query appear first in the index. After a search query is received from a user the index is traversed in an order determined by the sortrank value. Responsive web pages are presented to the user in an order determined by a search engine ranking algorithm.