Keywords: Social media, big data, sentiment analysis, and emerging technologies

With the advent of digital media, there is not only drastic changes in individuals’ information consumption behaviors, but also prompts credibility concerns among users. The percentage of users who expressed major apprehensions about online information, albeit small, has been increasing since 2012 from 12% to 15%. The level of trust decreases even more when looking at the views of social media, in which only 11% of internet users believe that social media information is reliable (Cole, Suman, Shramm, & Zhou, 2016). At a time when misinformation is commonly found online, and more and more people are getting their news and information from social media, understanding how individuals perceive credibility of political information is important. Moreover, previous research has shown the importance of social endorsement used as heuristics in credibility perceptions (Messing & Westwood, 2012; Metzger, Flanagin, & Medders, 2010). In a review of literature, Bellur and Sundar (2014) explained the mediating role of heuristics in making judgements and evaluations. The authors recommend a moderated mediation model to examine the role of heuristic. In the present study, this model is tested in the context of social endorsement on Facebook. Using a 2 (Prime: present vs. absent) by 2 (social endorsement: high vs. low likes) experimental design, participants are first exposed to a prime for using social endorsement as a heuristic followed by two Facebook posts. The prime is used to test the mediating role of heuristics in perception of credibility. The participants who are exposed to the prime read a brief report on how Facebook “likes” have been related to reliability of the information.
H1: Participants who are in the high “likes” condition will perceive the Facebook post more credible compared to those who are in the low “likes” condition.
H2: Participants who are in the prime condition will perceive the Facebook post more credible compared to those who are in the no prime condition.
H3: Self-reported heuristic use mediates the relationship between social endorsement and credibility perceptions.
Two experiments were conducted to test these hypotheses. The moderated-mediation models were tested using the PROCESS macro (Model 8) developed by Hayes (2013). Findings showed that participants in the high likes condition perceived the post more credible [B = .063, SE = .05, p < .001]. Similarly, the findings also show that the second hypothesis was supported demonstrating that participants who were primed before the Facebook manipulation perceived the post as more credible [B = .057, SE = .05, p < .001]. Finally, the results show the mediating role of the self-reported heuristic use [B = .054, SE = .05, p < .001] supporting the third hypothesis of the study. Priming the individuals moderates this relationship such that those participants who were in the prime condition show stronger perceptions of credibility in the high “likes” condition. This study takes the first step in understanding the mechanism behind the use of heuristics in terms of social endorsement in Facebook.