Marketing & consumer behavior
Subjective norm scale: TPB and social influence
- Concept
- Subjective Norm
- Field
- Marketing & consumer behavior
- Scales in the library
- 3
- Items
- 12
Subjective norm is a person's perception of whether people important to them want them to perform a behavior. It is one of the three determinants of intention in the Theory of Reasoned Action (TRA) and Ajzen's Theory of Planned Behavior (TPB). In UTAUT and UTAUT2, the corresponding concept is called social influence. Common thesis topics in Vietnam include intention to buy green products, students' entrepreneurial intention, vaccination intention, and intention to use e-wallets.
Comparing the scales
| Scale | Author (year) | Items | Response format | When to use it |
|---|---|---|---|---|
| Subjective Norm (SN) Theory of Planned Behavior (TPB) scale | Francis et al. (2004) | 5 | Likert 7-point | Choose this when your model follows TPB or TRA; includes both injunctive and descriptive norms (SN5), applicable to most behaviors. |
| Social Influence (SI) UTAUT2 scale | Venkatesh et al. (2012) | 3 | Likert 7-point | Choose this for consumer technology theses following UTAUT2; 3 items ask only about important others, with no organizational element. |
| Social Influence (SI) UTAUT scale | Venkatesh et al. (2003) | 4 | Likert 7-point | Choose this for technology in organizations; SI3 and SI4 ask about support from management. |
Items of each scale
Original English wording from the published source. Replace placeholders such as [system] or
[brand] with what your study is about, and pilot the questionnaire with 20 to 30 respondents first.
Subjective Norm (SN) · Theory of Planned Behavior (TPB) scale
| Code | Item |
|---|---|
| SN1 (R) | Most people who are important to me think that I should 1 2 3 4 5 6 7 I should not [perform the behavior]. |
| SN2 | It is expected of me that I [perform the behavior]. |
| SN3 | I feel under social pressure to [perform the behavior]. |
| SN4 | People who are important to me want me to [perform the behavior]. |
| SN5 | Most people like me [performed the behavior]. (unlikely 1 2 3 4 5 6 7 likely) |
Source: Francis et al. (2004). Response scale, licence and APA reference: Theory of Planned Behavior (TPB) scale.
Social Influence (SI) · UTAUT2 scale
| Code | Item |
|---|---|
| SI1 | People who are important to me think that I should use [mobile Internet]. |
| SI2 | People who influence my behavior think that I should use [mobile Internet]. |
| SI3 | People whose opinions that I value prefer that I use [mobile Internet]. |
Source: Venkatesh et al. (2012). Response scale, licence and APA reference: UTAUT2 scale.
Social Influence (SI) · UTAUT scale
| Code | Item |
|---|---|
| SI1 | People who influence my behavior think that I should use [system]. |
| SI2 | People who are important to me think that I should use [system]. |
| SI3 | The senior management of this business has been helpful in the use of [system]. |
| SI4 | In general, the organization has supported the use of [system]. |
Source: Venkatesh et al. (2003). Response scale, licence and APA reference: UTAUT scale.
(R): reverse-coded item; recode before analysis. Theory of Planned Behavior (TPB) scale: 1–7 scale: new score = 1 + 7 − score = 8 − score. For adjective pairs with the positive pole on the left, reverse so that a high score always means the positive pole.
Tips
- TPB item SN1 uses the anchors 'should ... should not' and must be reversed. If you switch to an agreement Likert scale, rewrite it as 'Most people who are important to me think that I should...'.
- If an item has a low loading and is dropped, report the loading and the reason, and re-check the content validity of the construct after dropping it in the results chapter.
- Replace [perform the behavior] with a specific behavior and time frame, as in the intention scale, so that the TPB constructs match.
- Do not use UTAUT's SI3 and SI4 for individual consumers because there is no management or organization behind them.
Once you have a scale, put the concept in the research model drawer to state your hypotheses, work out the minimum sample size, and after data collection check reliability with the Cronbach's alpha calculator.
Frequently asked questions
Are subjective norm and social influence the same?
Almost. Venkatesh et al. (2003) merged subjective norm, social factors, and image into social influence in UTAUT. If your model follows TPB, call it subjective norm; if it follows UTAUT, call it social influence.
What is a descriptive norm and should I include it?
A descriptive norm is the perception of whether people like oneself are doing the behavior (item SN5). Ajzen recommends measuring both types. If SN5 has a low loading, it can be split off as a separate construct.
Why is subjective norm often not statistically significant?
The meta-analysis of 185 studies by Armitage and Conner (2001) shows subjective norm is the weakest predictor of intention among the three TPB predictors. A non-significant result is therefore still a valid finding and should be discussed, especially for personal behaviors.
References
- Armitage, C. J., & Conner, M. (2001). Efficacy of the theory of planned behaviour: A meta-analytic review. British Journal of Social Psychology, 40(4), 471–499. https://doi.org/10.1348/014466601164939