Revisiting the social enhancement hypothesis: Extroversion indirectly predicts number of Facebook friends operating through Facebook usage Gina Masullo Chen ⇑ The University of Texas at Austin, School of Journalism, 300 W. Dean Keeton St., Austin, TX 78712-0113, USA article info Article history: Keywords: Social media Personality theory Facebook Friending Extroversion Social enhancement hypothesis abstract An online survey of college-age Facebook users (N = 209) found that extroversion, narcissism, openness, and agreeableness predicted friending more people on Facebook. However, only extroversion continued to exert an effect when these and other personality variables were examined together in one regression model, while controlling for frequency of Facebook usage and gender. Also, a path analysis model showed that extroversion directly predicted number of Facebook friends and the number of months people were active on Facebook. In addition, extroversion indirectly influenced number of Facebook friends, operating through months active on Facebook and hours per week spent on Facebook in a parallel mediation effect. Findings offer support for the social enhancement hypothesis, which argues that extroverted people ben- efit the most from social media. Ó 2014 Elsevier Ltd. All rights reserved. 1. Introduction Researchers for decades have tried to understand how personal- ity shapes social interactions among people. Social-networking sites, such as Facebook, offer an opportunity to study these interac- tions. Research has found that personality shapes how people com- municate online, much as it does offline (e.g. Amichai-Hamburger & Vinitzky, 2010; Back et al., 2010). Based on this foundation, it is well established that personality has an effect in how people use social- networking sites. However, what has received less study is how this effect plays out – what path does this effect takes? This current study used a survey of college-age Facebook users (N = 209) to begin to fill this gap by exploring a mediation model that explains how personality and Facebook usage predict number of Facebook friends. To create this model, this study drew on personality theory and the social enhancement hypothesis, which argues that people who are popular offline complement this popularity online (Kraut et al., 2002; Tufekci, 2010; Zywica & Danowski, 2008). Previous research has examined similar variables (Amichai-Hamburger & Vinitzky, 2010; Ross et al., 2009; Schrammel, Koffel, & Tscheligi, 2009). However, no earlier studies have directly tested a mediation model that examines the effect of personality on friending mediated by how frequently people use Facebook. Therefore, this study offered new knowledge about the role personality plays in human behavior by moving beyond merely describing the influence to explaining its path in the microcosm of a social-networking site. First, I offer a brief history of the role of friending on Facebook. Then I review the literature on how personality theory and the social enhancement hypothesis have been applied to social media to show support for the hypotheses and research question in this study. Then I outline how the proposed model was tested and explain how the results fit existing literature and expand knowledge of how personality influences social media use. 2. Literature review 2.1. Facebook Social media have been around in some form since the early 1990s, even before the Internet was called the World Wide Web (Rheingold, 2000). Their goal was to enable people to form online connections with other people, a goal that continued as these sites became more technologically sophisticated (Thelwall, 2008). Face- book started as a social medium for college students in 2004 (Boyd & Ellison, 2007) but two years later was opened to the general pub- lic and now has become the number one website in the world, according to the traffic-ranking site, Alexa.com. 1 Facebook has 1.06 billion monthly active users (Tam, 2013). Two-thirds of online American adults report using it, making it the predominant social medium in the United States (Rainie, Smith, & Duggan, 2013). As such, Facebook was deemed a suitable environment in which to understand online communication because of its widespread and frequent use. College-age people were the target of this study http://dx.doi.org/10.1016/j.chb.2014.07.015 0747-5632/Ó 2014 Elsevier Ltd. All rights reserved. ⇑ Tel.: +1 228 229 2783. E-mail address: savethemedia@gmail.com 1 According to figures at http://www.alexa.com accessed on June 30, 2013. Computers in Human Behavior 39 (2014) 263–269 Contents lists available at ScienceDirect Computers in Human Behavior journal homepage: www.elsevier.com/locate/comphumbeh