This dissertation proposes a new paradigm that may lay the groundwork for analyzing various aspects of online users' behaviors. The main idea of this paradigm is that a user's behavior in a virtual society is the projection of his psyche, which is peculiarly developed online. In order to explore this idea, the current study initiates the discussion from the validation of the existence of a virtual ego. The first essay empirically shows that the developmental levels of the real ego and the virtual ego are different from each other. More specifically, when the developmental level of the real ego is high, the development stage of the virtual ego is lower and vice versa. From this empirical finding, the existence of a virtual ego is implied. This empirical finding is supported by the theory of ego states in the second essay. A model of a virtual ego state combining this theory of ego state and a theory of reference frame is proposed.

Based on the findings of the first and the second essays, the third essay proposes that the virtual ego development has two dimensions, the developmental level of the virtual ego and the progress of a virtual ego state. The dimensionality of the virtual ego development and its determinants are empirically explored. Also, it is investigated how these dimensions of virtual ego make influences on the relationships between anonymity and virtual behaviors such as noninteractive, hostile-interactive, and collaborative behaviors. As result, it is shown that anonymity affects virtual behavior in both positive and negative ways depending on the dimensions of virtual ego development. It is also examined that users' virtual behaviors affect their e-loyalty toward their virtual residences, which is moderated by dimensions of virtual ego development.

The main contributions of this research are three fold. First, this research proposes a completely new paradigm explaining users' online behaviors. Second, this research provides managerial insights into the successful social networking and online game business. Third, this research will open the gate for a new research stream applying psychiatry to the area of IS. Now that we have virtual world, it would be demanding to talk about people living in the virtual world.

Key Words: virtual ego, online persona, online identity, virtual experience, virtual behavior, virtual residence, anonymity