Title: Does Liking by ‘Friends’ Enhance Persuasion? An Experimental Investigation in Social
Media
Authors: Dezhi Yin, Sam Bond, Han Zhang (all from Georgia Institute of Technology)
Abstract: In contrast to traditional advertising, social media platforms allow ads to be framed
according to the social context of the user. For example, a common assumption is that
endorsement by ‘friends’ can leverage the power of social influence and increase advertising
persuasiveness (e.g., Facebook ads ‘liked’ by friends, ‘Sponsored Stories’). Drawing on theories
of source credibility and persuasion knowledge (e.g., Friestad and Wright 1994), this paper
suggests a more complex relationship. We argue that compared to others in general, ‘friends’ are
perceived as more credible sources of product/service information; however, the presence of
friends in an advertisement also activates cognitions regarding ulterior motives of the endorsers
and the appropriateness of the endorsing behavior. As the social distance of the endorser
increases, his/her credibility diminishes rapidly but concerns about motives and appropriateness
remain. Given sufficient social distance, therefore, a friend’s endorsement may even diminish
advertising persuasiveness. These ideas were investigated using a between-subjects experimental
design. Participants were asked to evaluate a hotel advertisement in one of three conditions:
absence of friend endorsement (control), distant friend endorsement, and close friend
endorsement. Analysis of attitude and choice measures revealed a common pattern: participants
favored the hotel whose ad was endorsed by a close (vs. distant) friend. Furthermore, the control
ad was significantly more persuasive than that endorsed by a distant friend (differences between
control and close friend conditions were not significant). These findings highlight the importance
of considering persuasion knowledge in social media contexts, offering important practical
implications for the implementation of social advertising.
Keywords: social advertising, persuasion knowledge, social distance, recommendations,
electronic commerce, consumer decision-making