The Theory of Reasoned Action

In his exploration of the parameters of Persuasion, Miller (1980; see Chapter 1 in this volume) wrote that Persuasion was an indirectly coercive process. His position was based on two arguments. First, he suggested that any coercion that accompanied Persuasive attempts was a natural part of the social process. For example, by voting for Candidate X in an election, the voter is potentially deprived of any of the benefits of being represented by Candidate Y or Candidate Z. Miller also argued that when Persuasion involved more direct coercion, it occurred only after a Period of reasoned message exchange. In essence, Miller's position was that Persuasion is a process of influencing behaviors that are voluntary and necessarily involve conscious decision making—in other words, volitional behaviors. Over the years, considerable attention has been paid in both academic research and applied communication campaigns to modifying volitional behaviors.

Born largely out of frustration with traditional attitude-behavior research, much of which found weak correlations between attitude measures and Performance of volitional behaviors, Fishbein and Ajzen (1975, 1980) developed the theory of reasoned action (TRA). Their work, and the research that it has spawned, is the focus of this chapter. Before proceeding to an evaluation of that body of research, we present a brief explication of the theory and its components.

An Explication of the Theory of Reasoned Action

The aim of the TRA is to explain volitional behaviors. Its explanatory scope excludes a wide range of behaviors such as those that are spontaneous, impulsive, habitual, the result of cravings, or simply scripted or mindless (Bentler & Speckart, 1979; Langer, 1989). [Page 260]Such behaviors are excluded because their Performance might not be voluntary or because engaging in the behaviors might not involve a conscious decision on the part of the actor. The TRA also excludes from its scope those behaviors that may require special skills, unique opportunities or resources, or the cooPeration of others to be Performed (Liska, 1984). One may be prevented from Performing a behavior because of a skill deficit, lack of opportunity, or lack of cooPeration from others and not because of a voluntary decision not to engage in the behavior.

Behavioral Intentions, Attitudes, and Subjective Norms

The TRA posits that the strongest or most proximal predictor of volitional behavior is one's behavior intention. Behavioral intentions are thought to be the result of both an individual influence and a normative influence. The individual influence on intention is a Person's attitude toward Performing the volitional behavior. The normative influence on intention is what Fishbein and Ajzen referred to as one's subjective norm. In its simplest form, the TRA can be expressed as the following mathematical function:

where BI represents one's behavioral intention. The behavioral intention is a function of both AB (one's attitude toward Performing the behavior) and SN (one's subjective norm related to Performing the behavior), and the Ws represent empirically derived weights.

An attitude, as it relates to the TRA, is an affective or valenced response toward Performing some behavior and not toward some generalized attitude object. If the object of a communication campaign was to induce people to eat five helpings of fruits and vegetables a day, then a target Person's relevant attitude would be the degree to which he or she felt positively or negatively toward eating five helpings of fruits and vegetables a day. The attitude AB is weighted (W1) by the salience or importance of the attitude to the targeted Person. A subjective norm is a Person's belief about whether significant others feel that he or she should Perform the target behavior (e.g., do significant others feel that the target Person should eat five helpings of fruits and vegetables a day?). The influence of the subjective norm is also weighted (W2) by the salience or relative importance of the normative influence to the target Person.

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