我朋友的ppt，大家多多批评指正

曾哥：推荐网络多样性.pdf

给大家选三篇曾哥的工作供参考（均与此ppt无关）

Negative ratings play a positive role in information filtering [Physica A]

http://www.sciencedirect.com/science/article/pii/S0378437111005310
CAN DISSIMILAR USERS CONTRIBUTE TO ACCURACY AND DIVERSITY OF PERSONALIZED RECOMMENDATION? [IJMPC]

http://www.worldscinet.com/ijmpc/21/2110/S0129183110015786.html
Relevance is more significant than correlation: Information filtering on sparse data [EPL]
http://iopscience.iop.org/0295-5075/88/6/68008/