Applying Common Identity and Bond Theory to Design of Online Communities

Online communities depend upon the commitment and voluntary participation of their members. Community design — site navigation, community structure and features, and organizational policies — is critical in this regard. Community design affects how people can interact, the information they receive about one another and the community, and how they can participate in community activities. We argue that the constraints and opportunities inherent in online community design influence how people become attached to the community and whether they are willing to expend effort on its behalf. We examine two theories of group attachment and link these theories with design decisions for online communities. Common identity theory makes predictions about the causes and consequences of people's attachment to the group as a whole. Common bond theory makes predictions about the causes and consequences of people's attachment to individual group members. We review causes of common identity and common bond, and show how they result in different kinds of attachment and group outcomes. We then show how design decisions, such as those focused on recruiting newcomers versus retaining existing members, constraining or promoting off-topic discussion, and limiting group size or allowing uncontrolled growth, can lead to common identity or interpersonal bonds among community members, and consequently to different levels and forms of community participation by those so motivated.