[Objective] This study explores the structure of user interest hierarchy,as well as its evolution laws,aiming to improve the quality of personalized information services.[Methods] First,we used the LDA topic model to retrieve the topics of users’ tags.Then,we calculated the tag’s degree of interests,which were combined with their topics to identify user’s interests.Finally,we created the “core-edge” structure for user’s interests based on the interest network to analyze the evolution laws of their hierarchy.[Results] The “core-edge” str...