1. An information processing apparatus comprising: a first similarity degree calculating section which calculates the degree of similarity between a predetermined item and a calculation target item; and a related item determining section which determines the calculation target, items of a predetermined quantity as the related item of the predetermined item in the descending order of the degree of similarity, wherein meta information related to the calculation target item is added to the predetermined item based on behavior history of user so as to calculate the degree of similarity between the predetermined item and the calculation target item.