Tang Q Zeng/The journal of systems and Software 85(2012)87-101 recommender systems ting estimation method Mender systems social tagging Recommendatin system Content-based filtering Profile Injection Attacks Shiling The papers represented by circles are 1. Towards the Next Generation of Recommender Systems: A Survey of the State-of-the-Art and Possible Extensions 2. Evaluating Collaborative Filtering Recommender Systems 3. Ontological User Profiling in Recommender Systems 4. Enriching Ontological User Profiles with Tagging History for Multi-Domain Recommendations 5. Individual and Group Behavior-based Customer Profile Model for Personalized Product Recommendation Towards Trustworthy Recommender Systems: An Analysis of Attack Models and Algorithm Robustness Fig 3. An example of a paper-keyword relation modeL. F: \LAB JOKKS\Pajek Network lode1AI!(C权重)met(72) □a LayoutGrsplDnly Frevieas Redrwe sext ZoomOut Options Export Move Info uncertan reasoning structue exd ctMe component at danaus ama movshon per tune fhie ecog deta acquision hmodal co 2y matching Fig 4. A weighted keyword graph of the subject "artificial intelligence"demonstrated by PajekX. Tang, Q. Zeng / The Journal of Systems and Software 85 (2012) 87–101 91 Fig. 3. An example of a paper–keyword relation model. Fig. 4. A weighted keyword graph of the subject “artificial intelligence” demonstrated by Pajek