Extracting A Level of Social Relationship Utilizing Bluetooth Signal with Smartphones

Online social network applications explicitly define “friends” with equally weighted links among people. While it is necessary to treat every friend equally from the aspect of expanding friends networks, it is not suitable to do so for context aware services which provide users appropriate information from friend in proper timing. In this paper, we focus on wide spread smartphones and use them as tools to observe social intimacy in real space without affecting their life style. Since social intimacy is defined in the field of psychology using communication distance between people, we measured Bluetooth RSSI of the smartphone between people and used the values to extract social intimacy. We have examined with 19 people for a week, and as a result, we confirmed that our approach extracts social relationships with the average error of 9.2%.