1. 18th iaps Conference 2004, Vienna Austria Car Use in Households– Different Measures and Corresponding Behaviour Garvill, J 1,3., Marell, A 2,3., & Nordlund, A 1,3 1 Department of Psychology 2 Department of Business Administration 3 Transportation Research Unit, TRUM Umeå University, Sweden

2. Background Behaviour patterns are studied in a situation where the individual is constrained by the spouses behaviour A study of how a single car is distributed between the two adults in a households Research Questions Is the car is bound to a person Is the car is bound to some errand/s Can differences in car use in the household be explained by differences in spouses attitudes toward different travel modes and/or habits? Attitudes towards travel modes Actual behaviour Travel habits Actual behaviour

3. Participants 65 households in Umeå, Sweden Two adults / One car / 20 Km (one way) to work / 64 years Mean age - 44 years (Male 45 years, Female 43 years) Method Travel diary for 1 week (travel mode & type of trip) Questionnaire Attitudes towards different travel modes A normal trip made with car this time of year is: Boring – Fun; Expensive – Not expensive; Doesn't give exercise – Gives exercise; etc. (Total of 13 items) Travel habits Response frequency measure State the travel mode you would choose for the following trips: Meet someone at the train station; Visit a friend at the opposite side of town; Shopping downtown etc. (Total of 16 trips described)

4. Car Use in the Households – Is the car bound to errand/s? Is the car bound to a person?

5. Attitudes Toward Car as Travel Mode

6. Car Habits in the Households Response frequency measure (Verplanken, Aarts, & Van Knippenberg,1997) Car as travel mode was chosen 60 % or more Four types of households: Male No car habit (N=41) Male Car habit (N=24) Female No car habit (N=47)N = 34N = 13 Female Car habit (N=17)N = 6N = 11

7. Households Car Habits – HOUSEHOLD Car Use (as driver) Interaction effect (male x female car habit), F (1, 64) = 4.48, p =.038

8. Households Car Habits – MALE Car Use (as driver) Interaction effect (male x female car habit), F (1, 64) = 6.08 p =.017

9. Households Car Habits – FEMALE Car Use (as driver) Main effect (female car habit), F (1, 64) = 5.98, p =.017

10. Conclusions Car use in the households was person-bound 75 % of the total amount of car use in the households was by the male spouse The positive relation between male car use as driver and female car use as passenger indicates joint trips Female spouses uses the car but foremost as passenger with the male spouse as driver

11. Conclusions Car habits influence household car use, particularly male car habits The effect of male car habits is dependent of the female not having a car habit When the female has a car habit the effect of the male car habits disappears

12. Conclusions The male and female car habits co-varies If the male has developed a car habit the female is likely to have developed a car habit and vice versa Could indicate a competitative situation regarding the car as a constrained recourse between spouses with developed car habits Which is seen a reduction of the total amount of car use in the household