The Internet has grown explosively since its inception in early 1990s. In this study, we investigated the psychological mechanism to explain Internet usage. Website Acceptance Model (WAM), which is extended from Technology Acceptance Model (TAM), is presented by including the construct of perceived social influence (PSI). We investigated the relationship between PSI and two major belief constructs in TAM – perceived usefulness (PU) and perceived ease of use (PEU). Using a structural equation modeling, we found that (a) PSI does not have the significant direct effect on WWW usage, (b) PSI has stronger indirect effect on WWW use through PEU than through PU. These two results show that PEU is a complete mediator between PSI and WWW usage, and that WWW usage can be explained and predicted with the affect-related factors rather than the task-related issues.
Yang, Hee-Dong and Choi, Inyoung, "Web-site Acceptance Model (WAM):Perceived Social Influence on the Usage of a Web-site" (2003). ICEB 2003 Proceedings. 111.