In 2016, 23 universities chancellors had signed on an agreement on intercollegiate credit
exchanges through Seoul Chancellor Forum. So far, since colleges have recognized others as
competitors, this agreement is a rare case where colleges agee to cooperate each other on their
own initiative without the government’s intervention. However, not all colleges in Seoul have
participated in this Forum. This study investigates the context of this agreement on their
collective behaviors and its consequences from the perspective of the exchange theory and the
game theory. Analysis shows that colleges with medium-to-lower reputations as well as small
sizes of student quarters tend to participate in this Forum, whereas those with higher reputations
and large-size student quarters do not. This divide among colleges results in a stratified network
among colleges. The Forum participation by students quarters assigned to colleges can be
accounted for with asset specificity. Small-sized colleges may overestimate the cost and risk of
enlarging college courses to meet students’ needs and so prefer exchanging credits among
colleges to making new courses on their own. As a consequence of stratified network among
colleges, minor core colleges choose to pursue independent strategies, while the peripheral
majority of colleges pursue cooperative strategies for mutual symbiosis. Majorities of colleges
are in an interdependent status due to small sizes and so develop the relationship of reciprocal
exchange with other colleges. Prestigious colleges have capacity to deal with exterior shocks
independently and no incentives to pursue functional complementarity from other colleges. This
study reconfirms the requirement of reciprocity for cooperation to enact.