In recent years, social commerce has emerged as an important arena of electronic commerce (e-commerce). The concept of social commerce refers to any business activities that are mediated by social media or social networking sites (Curty and Zhang, 2013). To embrace social commerce, a primary online practice for many companies is to establish an identity, also known as a company’s brand page, on social networking sites such as Facebook or Twitter (Zadeh and Sharda, 2014). In fact, Fortune 500 companies have shown increasing interest in using Facebook, Twitter, blogs, and self-hosted online communities to enable interactions with consumers (Culnan et al., 2010). A recent report by Barnes and Lescault (2014) highlighted that 83% of Fortune 500 companies have already created brand microblogs on Twitter, and 80% have Facebook brand pages. For companies, creating a brand page on a social networking site is merely a step towards engaging in social commerce. However, much still remains unknown regarding how to achieve success in this emerging context (Zhang et al., 2015). Recent studies have shown a growing interest in some important dependent variables of social commerce. For instance, Liang et al. (2011) developed the concept of social commerce intention. They referred to it as the degree to which online users are likely to receive and share commercial, shopping, or product information on social networking sites. Hajli (2014) followed the same direction and investigated whether social support and relationship quality positively affected social commerce intention on Facebook. Similarly, Zhang et al. (2014) contended that social commerce intention may be influenced by technological environments and virtual consumer experiences. Another line of research emphasizes consumers’ purchase behavior stimulated by social networking sites. Wang and Chang (2013) conducted an experiment on Facebook and showed that tie strength and perceived diagnosticity of recommendations affected consumers’ decisions to buy recommended products. Ng (۲۰۱۳) examined purchase intention by considering the mediating effect of trust on social networking sites and the moderating effect of culture. Finally, Kim and Park (2013) found that the characteristics of social commerce firms influenced consumers’ trust in firms, which in turn affected purchase intention.