1. An information processing device comprising: acquisition means for acquiring data for pages of a site; extraction means for extracting a word appearing within said pages using said data for said pages acquired by said acquisition means; counting means for counting the number of times said word extracted by said extraction means appears within said pages; first generating means for analyzing a link structure between said pages acquired by said acquisition means, and for generating first weightings for between said pages in link relationships using a count value by said counting means; second generating means for generating second weightings for between pages in link relationships with a prescribed page using said first weightings generated by said first generating means; third generating means for generating at least one of SDF data and CDF data using said second weightings generated by said second generating means; and calculating means for calculating a prescribed value through page model extension processing based on at least one of ISDF and ICDF using said data generated by said third generating means.