ABSTRACT
In this study, we experimentally investigate collaborative scientific activities that are undertaken through a virtual space such as the Internet. In such cases, a partner has two aspects: an imaginary partner with whom the problem solver seems to work together, and an actual partner with whom he/she actually works. We design an experimental environment in which we can control the two factors independently. The experimental result shows: (1) a bias appearing in human behavior, such as the positive test bias in hypothesis testing, was not influenced by the change of an actual partner; however (2) the degree of using information given by a partner, such as reference to a partner's hypothesis, varied considerably with the change of an actual partner. Neither phenomenon above depended on the type of imaginary partner.
