Technology Acceptance Model

Fundamentals

TAM is an extension of the theory of reasoned action, introduced by Fred Davis in 1989, that has found a prominent place in the information systems literature as a reliable and parsimonious theory of technology acceptance. The latter characteristic, parsimony, is not just extant in the paucity of constructs and linking relationships of the theory but also in its theoretical transparency to the average person. Thus, TAM can be easily explained and accepted at face value by a lay audience, while simultaneously passing the rigor of theoretical and empirical testing fairly well. The use of TAM findings in a prescriptive manner is chief among its shortcomings.

The TAM posits that when a user is considering use of a new technology, the user forms two key perceptions (beliefs) regarding the technology: perceived usefulness and perceived ease-of-use. These beliefs are formed from external and internal influences at the individual (i.e., experience) and social level (culture, organizational policy, group norms, etc.). From these beliefs, an attitude toward using is formed by the user. Finally, intention to use is theorized as a key determinant of actual use. External variables, such as specific technology characteristics and individual attributes, are posited to be mediated by, and even antecedents to, beliefs. Perceived usefulness was originally defined by Davis in 1989 [Page 830]as “the degree to which a person believes that using a particular system would enhance his or her job performance” and perceived ease-of-use as “the degree to which a person believes that using a particular system would be free from physical and mental effort” (p. 320). Thus, the more an individual believes that a technology will enhance their job performance and the less they believe the effort will be in using the technology, the greater the intention to use it. The original theory also included the specification of external variables that would have influence on perceived usefulness and perceived ease-of-use. In early studies, these external variables were chiefly technology characteristics, but that would change quickly.

Over the past two decades, the TAM has been empirically tested and has evolved from its initial model to incorporate greater breadth of external influences, antecedents of the principal independent variables, and testing of theoretical relationships between constructs. Researchers would find that intention to use (i.e., behavioral intention) was a better predictor of actual use and that attitude toward use was neither empirically or theoretically necessary in the model. Furthermore, comparisons of the TAM to the theory of planned behavior and the theory of reasoned action showed that the TAM was equally as predictive, and greatly more parsimonious, than either of the more sophisticated models at predicting intention to use. A new model, TAM2, introduced by Viswanath Venkatesh and Davis a decade after TAM, incorporated social influence (e.g., subjective norms, voluntariness, image, etc.) and cognitive process (e.g., job relevance, output quality), related constructs that had been explored and validated by researchers over the first decade of empirical and theoretical refinement. TAM2 was found to be a valid expanded specification of the original TAM model in a series of four longitudinal studies in both voluntary and involuntary implementation settings. TAM2’s incorporation of additional construct antecedents, systems characteristics, and contextual measures responded well to the oft-stated criticism of theoretical simplicity. A final revision by Venkatesh and Hillol Bala in 2008, called TAM3, further specified antecedents to perceived usefulness from TAM2 and included work introduced on anchoring and adjustment from research on framing in decision making as antecedents of perceived ease of use, which fully specified and merged the preceding two decades of research of TAM into a single model.

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