Theory of reasoned action

The Theory of Reasoned Action (TRA) is a model that finds its origins in the field of social psychology. This model developed by Fishbein and Ajzen ( 1975 ) defines the links between beliefs, attitudes, norms, intentions, and behaviors of individuals. According to this model, a person’s behavior is determined by its behavioral intention to perform it. This intention is itself determined by the person’s attitudes and his subjective norms towards the behavior. Fishbein and Ajzen (1975, p. 302) define the subjective norms as “the person’s perception that most people who are important to him think he should or should not perform the behavior in question” (Fishbein and Ajzen 1975, p.302)

This theory can be summarized by the following equation:

Behavioral Intention = Attitude + Subjective norms

According to TRA, the attitude of a person towards a behavior is determined by his beliefs on the consequences of this behavior, multiplied by his evaluation of these consequences. Beliefs are defined by the person’s subjective probability that performing a particular behavior will produce specific results. This model therefore suggests that external stimuli influence attitudes by modifying the structure of the person’s beliefs. Moreover, behavioral intention is also determined by the subjective norms that are themselves determined by the normative beliefs of an individual and by his motivation to comply to the norms.

Theory of Reasonned Action from Davis, Bagozzi et Warshaw (1989)

TRA also claims that all other factors which influence the behavior only do so in an indirect way by influencing the attitude or subjective norms. Fishbein and Ajzen ( 1975 ) refer to these factors as being external variables. These variables can be for example, the characteristics of the tasks, of the interface or of the user, the type of development implementation, the political influences, the organizational structure, etc. (Davis, Bagozzi and Warshaw, on 1989). A meta-analysis on the application of the theory of reasoned action showed that the model can produce good predictions of choices made by an individual when facing several alternatives (Sheppard, Hartwick, and Warshaw, on 1988).

References

FISHBEIN, M.A. et AJZEN, I. (1975). Belief, attitude, intention and behavior: an introduction to theory and research, Reading, MA, Addison Wesley.
DAVIS, F.; BAGOZZI, R.; and WARSHAW, R. (1989). User Acceptance of Computer Technology: A Comparison of Two Theoretical Models. Management Science, Volume 35, 1989, pp. 982-1003.
SHEPPARD, B.H., HARTWICK J., & WARSHAW. P.R. (1988). The theory of reasoned action: A meta-analysis of past research with recommendations for modifications and future research. Journal of Consumer Research, Vol. 15, 1988, pp. 325-343.