Psychological predictors in context: Travel intentions among university staff and students

1. Psychological predictors in context: Travel intentions among university staff and students Rob Wall Institute of Energy and Sustainable Development De Montfort University Leicester, UK July 2004 rwall@dmu.ac.uk www.iesd.dmu.ac.uk Institute of Energy and Sustainable Development

2. Research aims • To identify psychological influences on drivers’ intentions to reduce or maintain their car use • To understand how psychological influences interact with contextual conditions Institute of Energy and Sustainable Development

3. Background to the study • Focus on drivers • Based on Schwartz’s Norm-activation theory (NAT) and Ajzen’s Theory of planned behaviour (TPB) • Two most common theories in environmentally significant behaviour research • Emphasise different behavioural motivations: altruistic and subjective expected utility • Added influence of people’s context on their intentions Institute of Energy and Sustainable Development

4. Awareness of consequences (AC) Personal norm (PN) Behaviour Ascription of responsibility (AR) Norm-activation theory (NAT) • Shalom Schwartz (1977) • Explains ‘altruistic’ behaviour • PN experienced as feeling of personal obligation to act • PN activated by: • Awareness of consequences for valued objects (AC) • Ascription of responsibility to self for consequences (AR) Institute of Energy and Sustainable Development

5. Attitude toward the behaviour (Att) Subjective norm (SN) Intention Behaviour Perceived behavioural control (PBC) Theory of planned behaviour (TPB) • Icek Ajzen (1991) • General theory of social behaviour • Behaviour follows from Intention, which is determined by: • Attitude toward the behaviour (Att) • Perceived control over performing the behaviour (PBC) • Subjective norms surrounding the behaviour (SN) Institute of Energy and Sustainable Development

6. Method • Participants were De Montfort University staff and students • Data collected by questionnaire in April 2003 • 1014 questionnaires returned, 312 drivers used in analysis • Data gathered on: • Norm-activation theory variables • Theory of planned behaviour variables • aspects of physical context (e.g. journey time) • socio-demographics (e.g. age, income) • Drivers intentions to maintain or reduce car use for commute during next 12 months • Logistic regression used to test explanatory power Independent variables Dependent variable Institute of Energy and Sustainable Development

7. Exploratory analysis AC = awareness of consequences of car use AR/PN = responsibility and obligation for reducing own car use Att = Attitude toward own car use PBC = perceived control over reducing own car use SN1 = pressure from friends to reduce car use SN2 = pressure from “people I know” to reduce car use • Factor analysis • ‘Reducers’ had higher mean scores on ‘anti-driving’ scales • ‘Maintainers’ had higher mean Attitude score • But even ‘reducers’ were very positive about driving • Significant (p < .05) differences on all variables except SN2 Institute of Energy and Sustainable Development

8. Bicycle ownership (+) Perceived cost of car travel (+) Journey time from home to DMU (-) Perceived journey distance (+) Results: Logistic regression • Stepwise logistic regression • AR/PN and PBC were significant (p < .05) psychological predictors • AR/PN had the strongest influence on intentions • Eight (of 13) contextual variables were also significant (p < .05) Taking passengers to DMU (-) Age (-) Full-time (-) or part-time (+) Income level (-) • Explained 48.1% of variance in intentions Institute of Energy and Sustainable Development

9. Results: PBC-AR/PN interaction • Differences across AR/PN levels • With low PBC, AR/PN level made 12.8% difference to intentions • With high PBC, AR/PN level made 20.1% difference • AR/PN has greater effect when PBC is high (additive effect) • Supported by correlations between AR/PN and intentions • Low PBC φ = .16 (p = .020) • High PBC φ = .24 (p < .001) Institute of Energy and Sustainable Development

10. Weak Strong Maximum likelihood of acting on psychological motivations Influence of AR/PN on intentions Inhibiting Moderate Facilitating Contextual influences Additive effects • Similar interactions between AR/PN and some contextual variables • Feelings of responsibility and obligation had greater influence on intentions when participants… • Owned a bicycle • Took no passengers in their car to university • Perceived driving as expensive Institute of Energy and Sustainable Development

11. Weak Strong Maximum likelihood of acting on psychological motivations Influence of AR/PN on intentions Inhibiting Moderate Facilitating Contextual influences The ‘A-B-C’ model • Guagnano et. al. (1995) proposed an alternative to additive • In their ‘Attitude-Behaviour-Context’ model, the influence of psychological factors is greatest when the influence of contextual factors is moderate • When context makes behaviour easy, strong motivation isn’t needed • When context makes behaviour hard, even strong motivation insufficient Institute of Energy and Sustainable Development

12. Results: An ‘A-B-C’ interaction • One interaction followed the ‘A-B-C’ model • People whose journey took a medium time (21-40 mins) were more likely to intend to reduce car use than those whose journeys were short (≤ 20 mins) or long (> 40 mins) • They also showed the only statistically significant correlation between AR/PN and intentions • ≤ 20 mins τ = .13 (p = .203) • 21-40 mins τ = .30 (p < .001) • > 40 mins τ = .21 (p = .054) Institute of Energy and Sustainable Development

13. Conclusions and implications • Interventions could target: • Feelings of responsibility and obligation for reducing car use • Perceived control over reducing car use • Responsibility and obligation have most effect when PBC is high • And when certain contextual conditions are present: • Bike ownership • No passengers • Perception of driving as expensive • So interventions should also take account of drivers’ context Institute of Energy and Sustainable Development