Assignment

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THEORY OF REASONED ACTION AND THEORY OF PLANNED BEHAVIOR

FISHBEIN AND AJZEN’S THEORY OF REASONED ACTION

 Originally developed in 1967; further developed during the 1970’s. By the 1980’s, very commonly used to study human behavior

History:  Originated in the field of social psychology.  The concept of “attitude” as a trigger and predictor of human behavior.

 Value‐Expectancy theory

ASSUMPTIONS OF THE MODEL

 Human behavior is under the voluntary control of the individual

 Man is “basically a rational information processor”  “Beliefs, attitudes, intentions, and behaviors are influenced by the

information available...”  People think about the consequences and implications of their actions

behavior the decide whether or not to do something.  A model that assumes the people are “rational actors”; NOT a model of

“rational behaviors”

 Therefore, intention must be highly correlated with behavior.  Whether or not a person intends to perform a health behavior should

correlate with whether or not they actually DO the behavior  Distinguishes between attitude toward an object and attitude toward a

behavior (e.g., Attitude toward breast cancer vs. Attitude toward mammography)

BEHAVIORAL INTENTION

 Perceived likelihood of performing the behavior  Must be a “firm” indication of intent  Affecting “intent” is the goal of a TRA based intervention

THEORY OF PLANNED BEHAVIOR

 http://www.people.umass.edu/aizen/tpb.diag.html

Behavior Behavioral  Intention

Subjective  Norm

Attitude Toward Behavior

Motivation to  comply

Normative Beliefs

Evaluations of  Behavioral Outcomes

Behavioral Beliefs

Theory of Reasoned Action

ATTITUDE TOWARDS BEHAVIOR  Behavioral Belief

 Belief that behavioral performance is associated with certain attributes or outcomes (i.e., What will happen if I engage in this behavior?)

 Influential factors?  Past experience  Information received or not received  Social influences (family, peers, etc.)

 Evaluation  Value attached to a behavioral outcome or attribute (i.e., Is this outcome desirable or undesirable)

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SUBJECTIVE NORM

 Normative Belief  Belief about whether each referent approves or disapproves of the behavior (i.e., others’ expectations)

 Most influential referents? (Media, teachers, peers, parents, spouses, etc.)

 Motivation to Comply  Motivation to do what each referent thinks (e.g., do I want to do what they tell me? How much? Why?)

 Parents vs. Peers?

EXAMPLES

 Bob often engages in DUI behaviors.  Why?  Why would you do to change the behavior?

 Peter exercises does not exercise at all.  Why?  Why would you do to change the behavior?

 Emma does not take her diabetes medicine regularly.  Why?  Why would you do to change the behavior?

LIMITATIONS OF TRA

 Are there situations where one may want to do certain behavior (i.e., high intention) but does not perform the behavior?

 People who have little power over their behaviors (or believe they have little power).

 As a result, Ajzen added a third element to the original theory:  Perceived Behavioral Control

THEORY OF PLANNED BEHAVIOR

 Intention Behavior  Link is problematic when behavior is not fully under the individual’s control.

 Adds one component to the TRA

 Perceived Behavioral Control  To account for factors outside the individual’s control that may affect intention and behavior

 Based on the idea that behavioral performance is determined jointly by motivation (intention) and ability (behavioral control) (skills and resources)

 Best predictor of future behavior is past behavior

THEORY OF PLANNED BEHAVIOR

 Perceived Behavioral Control  A person’s perception of the ease or difficulty of behavioral performance

 Similar to self efficacy (Inc. w/ repeated successes)

 What characteristics is the person with a high perceived behavioral control likely to have?

Behavior Behavioral  IntentionSubjective 

Norm

Attitude Toward Behavior

Motivation to  comply

Normative Beliefs

Evaluations of  Behavioral Outcomes

Behavioral Beliefs

Theory of Planned Action

Control Beliefs

Perceived Power

Perceived  Behavioral Control

Behavior Behavioral  IntentionSubjective 

Norm

Attitude Toward Behavior

Motivation to  comply

Normative Beliefs

Evaluations of  Behavioral Outcomes

Behavioral Beliefs

Theory of Planned Behavior

Control Beliefs

Perceived Power

Perceived  Behavioral Control

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USES FOR TRA/TPB

 Volitional control: situations in which individuals can exercise a control over the behavior

 TRA works best with high volitional control  when applied to behaviors that are under the person’s control (or they think they are)

 TPB works best with low volitional control:  when the behavior is NOT perceived to be under the person’s control

LIMITATIONS

 Factors such as demographics and personality still not in model

 No clear definition of perceived behavioral control (hard to measure)

 Assumption that perceived behavioral control predicts actual behavioral control.

 The more time between behavioral intent and actually doing the behavior, the less likely the behavior will happen.

 Theory assumes people are rational and make systematic decisions based on available information. Ignores unconscious motives