Abstract
This paper proposes “visual summary”, which visualizes topics and those transitions in a thread of BBS (Bulletin Board System) based on interactive information visualization technique so that a user can grasp topic transition in a thread without reading the corresponding comments. Recently, various types of information is available on the Web, among which CGM (consumer generated media) such as BBS, blog and SNS (Social Networking Service) is one of unique information on the Web and it could be used for marketing by companies as well as decision making by individuals. Although topic transition in a thread of BBS is also useful information, it is difficult for a user to read a number of comments in a thread. The visual summary proposed in the paper visualizes the topic transition with animation, based on co-occurrence of keywords within a certain time period. A user can analyze a thread interactively by changing time window and focused keywords. An experimental result with test participants shows the effectiveness of the proposed visual summary for identification of topic transition pattern and estimation of topics. The result of analyzing participants' behaviors revealed that the participants used the same clues as those used when grasping topic transition by reading threads. The result also revealed the existence of reasonable analyzing behavior independent of participants.
