Crime Lead Discovery on Gray Forum Communities: A Case Study on a "Pirated-CD" Forum in Taiwan

Our society is in a state of transformation toward a "virtual society." However, due to the nature of anonymity and less observability, Internet activities have become more diverse and obscure. As a result, unscrupulous individuals or criminals may exploit the Internet as a channel for their illegal activities to avoid the apprehension by law enforcement officials. This paper examined a "Pirated-CD Forum" in Taiwan. We studied the characteristics and conducted a hot thread analysis based on forum statistical data. We also developed two content search schemes for retrieving postings containing inappropriate information items in the forum. The experiment results show that hot threads are correlated to inappropriate postings, but the retrieval effectiveness can be significantly improved by search schemes based on content analysis.