Abstract
Minority opinions can be of crucial importance to the diversity, productivity, and harmony of a group, but are often left unattended and unheard. Previous methods that tried to enhance minority influence are usually overly forceful and low on ecological validity. To overcome these pitfalls, we proposed a new intervention method called minority clustering and examined its effects with a social network experiment (N = 456). Minority clustering was implemented by increasing the network connections among participants with initial opinions that deviated from the mainstream opinion and forming an opinion cluster among these minority members. Our results show that minority clustering significantly slowed down the rate at which minority members shifted toward majority opinions, thereby sustaining minority cohesion, and moved majority members closer to minority opinions, thus enhancing minority influence. An additional filter bubble intervention, through which all members of a network were exposed to neighbors with similar opinions to their own, further strengthened minority cohesion but weakened minority influence. Minority clustering is an unobtrusive intervention that does not need overt cooperations of network members and can be implemented easily in social media platforms. The working mechanisms of minority clustering and its effects on group opinion formation are further discussed.