An operation method of an image display device used by users according to an embodiment of the present invention comprises the steps of: receiving user data of a user and user data of at least one user group; collecting viewing history information of the user and viewing history information of the at least one user group; extracting a plurality of user viewing patterns using the user data and the viewing history information; and providing a referral program corresponding to a user viewing pattern of a highest priority on a basis of priorities of the extracted user viewing patterns, wherein the user group includes at least two users among the plurality of users.