A communication analysis device updates statistical information on a content access based on the communication session log of a user. The content access is an aggregation of a plurality of communication sessions needed for browsing one website. The communication analysis device acquires session information pertaining to one communication session, and determines whether a lapsed time from the start time or end time of a base communication session to the start time or end time of the one communication session is equal to or less than a threshold value. When the lapsed time is equal to or less than the threshold value, the communication analysis device determines that the one communication session is included in the same content access as the base communication session, and updates the statistical information of the content access. The communication analysis device stochastically sets the threshold value based on a prescribed probability distribution.