1. Intelligent Database Systems Lab N.Y.U.S.T. I. M. Discovering Leaders from Community Actions Presenter : Wu, Jia-Hao Authors : Amit Goyal, Francesco Bonchi, Laks V. S. Lakshmanan CIKM (2009) 國立雲林科技大學 National Yunlin University of Science and Technology

2. Intelligent Database Systems Lab N.Y.U.S.T. I. M. 2 Outline Motivation Objective Methodology Experiments Conclusion Personal Comments

3. Intelligent Database Systems Lab N.Y.U.S.T. I. M. Motivation We have some interactions with you and me in the internet actives that can be a social networks.  like rating songs as in Yahoo! Music or Yahoo! Movies or users burying gadgets such as cameras, handhelds… Buy Write I want to buy.

4. Intelligent Database Systems Lab N.Y.U.S.T. I. M. Objective The authors want to find the leaders and tribe leaders from the social networks and action log. Buy Write Leader Actions log Tribe Leader Buy Actions log

5. Intelligent Database Systems Lab N.Y.U.S.T. I. M. Objective (Cont.) The authors want to find the leaders and tribe leaders from the social networks and action log. Social networks Action log Propagation of action a Propagation of action b

6. Intelligent Database Systems Lab N.Y.U.S.T. I. M. Objective (Cont.) If we know that there are a small number of leaders who set the trend for various actions.  Targeting them for adoption of new products could be profitable to the companies (Targeted advertising). Write

7. Intelligent Database Systems Lab N.Y.U.S.T. I. M. Methodology Parameters  ： maximum propagation time threshold  ： number of the node in action α  ： a number of actions by the user u Leader Tribe Leader Propagation of action a Propagation of action b

8. Intelligent Database Systems Lab N.Y.U.S.T. I. M. Methodology (Cont.) Leadership confidence Genuineness score of v Constraint 1. Constraint 2.

9. Intelligent Database Systems Lab N.Y.U.S.T. I. M. Methodology (Cont.) – Computing Influence Matrix Lock Bit Vector S T VWR 76543210 01010111 NodeInfVec STVWR R01010111 S01000110 T00010110 W00000110 V00000100 R ST W V RWVTS R11111 W01100 V00100 T01110 S01101

10. Intelligent Database Systems Lab N.Y.U.S.T. I. M. Methodology (Cont.) – Propagate Lock Bit Vector S T VWR 76543210 01010111 R ST W V P S T P VWR 76543210 01011111 P 00001000 R 01010111 OR R 01011111

11. Intelligent Database Systems Lab N.Y.U.S.T. I. M. Methodology (Cont.) – Update R ST W V P Q NodeInfVec STVWR R01010011 S01000010 T00010010 W00000010 V00000100 Lock Bit Vector S T VWR 76543210 01010111 SQT P VWR 76543210 01111111 P 00001000 NodeInfVec STPVWR R01011011 S01001010 W00001010 OR

12. Intelligent Database Systems Lab N.Y.U.S.T. I. M. Methodology (Cont.) - Computing Leaders Genuineness Leaders Tribe Leader

13. Intelligent Database Systems Lab N.Y.U.S.T. I. M. Experiments

14. Intelligent Database Systems Lab N.Y.U.S.T. I. M. Experiments (Cont.)

15. Intelligent Database Systems Lab N.Y.U.S.T. I. M. Experiments (Cont.) 75293 206280198671 68241 130514 170467 22380 130514 20045

16. Intelligent Database Systems Lab N.Y.U.S.T. I. M. Conclusion The authors purpose notions of leaders and tribe leaders together with possible additional properties such as confidence and genuineness. Use the two key operations – update and propagate to search the changes of social network graph. The result is the first proposal of a framework based on frequent pattern mining for discovering leaders in social networks.

17. Intelligent Database Systems Lab N.Y.U.S.T. I. M. Comments Advantage  An interest research about the community actions. Drawback  There have some parameters in algorithms and paper. Application  Viral Marketing.