| User acceptance of information technologies is an important issue since productivity gains associated with technology use can be achieved only if a particular technology is accepted and used by target users. This dissertation attempts to address five important issues related to user acceptance. The key research questions are listed below: (1) How do the different models of user acceptance (e.g., Technology Acceptance Model, Decomposed Theory of Planned Behavior, Innovation Diffusion Theory and a Model of PC Utilization) compare with each other in terms of predictive validity? We expect the Technology Acceptance Model (TAM), which comprises of perceived usefulness and perceived ease of use, to be the most powerful model predicting acceptance. (2) What are the determinants of perceived usefulness? We hypothesize that subjective norm and innovation characteristics to be the key determinants of perceived usefulness. (3) What are the determinants of perceived ease of use? We expect perceived behavioral control, computer anxiety, enjoyment, computer self-efficacy and objective usability to be the critical determinants of perceived ease of use. (4) Does behavioral intention indeed predict actual usage behavior or does it only predict self-reported usage behavior? We expect usage behavior (measured in terms of duration of use) to predict behavioral intention most effectively. (5) Are there any additional predictors of behavior? Typically, behavioral intention to use is the key predictor of usage behavior. The role of habit as an additional predictor of behavior is examined.; Two longitudinal studies were conducted to address the above issues. The first study among seventy-one student subjects spanned fifteen months of use of two systems, Minuet and CC:Mail. The second study among 1,235 users in 22 different organizations using a wide range of technologies spanned a five-month period. Strong support was found for the models proposed in this research. |
