Advances in Web Mining and Web Usage Analysis 9th International Workshop on Knowledge Discovery on the Web, WebKDD 2007, and 1st International Workshop on Social Networks Analysis, SNA-KDD 2007, San Jose, CA, USA, August 12-15, 2007. Revised Papers - Zhang, Haizheng; Spiliopoulou, Myra; Mobasher, Bamshad; Giles, C. Lee; McCallum, Andrew; Nasraoui, Olfa; Srivastava, Jaideep; Yen, John (Springer Berlin Heidelberg : Imprint: Springer, 2009)