Hiroshi Kato1), Keiichi Yamazaki2), Hideyuki Suzuki1), Hideaki Kuzuoka3), Hiroyuki Miki4), and Akiko Yamazaki5)
1) C&C Media Research Laboratories, NEC Corporation, 2)Faculty of Liberal Arts, Saitama University, 3) Institute of Engineering Mechanics, University of Tsukuba, 4)Media Laboratories, Oki Electric Industry Co. Ltd., and 5)Nursing School of Douai Hospital
Optimum arrangement of communication resources for a distance education system to support collaborative learning, including hand-manipulation of physical objects, was empirically investigated. The authors propose a 'body metaphor' concept, which follows the ordinary body arrangement in everyday instruction. It allows: (1) to display instructor's pointer; (2) to display instructor's face; (3) to display views of learner's orientation; (4) to arouse learner's awareness of being watched by the instructor; and (5) to dispose communication resources apart enough so as to clarify the learner's orientation.
Comparative experiments revealed that body metaphor setting supported smoother collaboration than the conventional face-to-face metaphor setting.
Keywords-- distance education, CSCW, collaborative learning, ethnomethodology, interaction analysis, video conference
Most of the distance education systems in use today have been built on the basis of a bi-directional video- mediated tele-conference system, i.e., views of a lecturer's face and/or learning material are transmitted to the learners' sites, and vice versa. In such a system, however, it has been pointed out that gaze, gestures, and other body movements are generally not as effective as in normal face-to-face communication _iHeath et al., 1991, 1992). Therefore, the prevailing systems are not sufficient, particularly for conducting collaborative learning in which non-verbal communication plays an important role, such as in a scientific experiment or in a physical exercise, although they may be acceptable for an education style like lectures in which symbolic (verbal or visual) information transmission from a teacher to learners is dominant.
Research in computer supported cooperative work (CSCW) has studied this problem mainly in regard to transmission of hand gestures and the question of eye contact. Some CSCW systems, such as VideoDraw ( Tang et al., 1990) and ClearBoard ( Ishii et al., 1992), have provided solutions in this respect. However, if one wants to use them in remote support for collaborative work involving manipulation of physical objects, which requires allowing for the objects to be spread out in a three-dimensional space and for participants to move around, they show clear limitations. In these cases, it is necessary to devise systems for supporting remote collaboration between many participants in different positions and different environments ( Kuzuoka et al., 1992, 1994, 1995) An essentially flat work- support system like ClearBoard cannot be turned into one that supports collaboration in three-dimensional space; and it is physically impossible to accomplish perfect eye contact if many participants are allowed to move around in the work space.
The purpose of this research is not simply to point out the physical limitations of these CSCW systems, but it is to try to delineate clearly the intrinsic limitations. We refer to the concept underlying in the distance education systems in use today as the 'face-to- face metaphor' (Figure 1), which ultimately aims to create an environment in which distant people talk as if in close face-to-face conversation. However, it is still not clear enough how the face view is used in collaboration, why it is helpful, and what arrangement of audio/visual resources is appropriate for collaboration.
We have performed some remote collaboration experiments with AlgoBlock, a computer tool for collaborative learning, by deploying cameras and monitors in distinct spatial arrangements. As regards the use of several cameras and monitors we were influenced by the work of Gaver and Heath on Multiple Target Video (MTV) ( Gaver et al., 1993, Heath et al., 1995) who analyzed which pictures are important and what kind of image people pay attention to. However, our pilot study conducted beforehand revealed