This workshop will explore the novel use of techniques from machine learning, data mining, text mining, information retrieval, statistics, information security and privacy, and user modelling, to identify patterns of potentially positive and negative activities in social media by examining the online content, social interactions, and user behaviours. It will also study the metrics in measuring the positive and negative impact of social media on individuals, business organizations, and government agencies. The analysis and mining of these patterns aim to promote positive activities in social medial, while at the same time reveal harmful aspects of social media and suggest ways to tackle and to overcome the negative side.