EFFECTS OF IMPLEMENTATION INTENTIONS ON THE ACTUAL PERFORMANCE OF NEW ENVIRONMENTALLY FRIENDLY BEHAVIOURS — RESULTS OF TWO FIELD EXPERIMENTS

In the context of two environmentally related behaviours (using a new bus route and shopping in a bio-shop) the implications of Gollwitzer's concept of implementation intention for Ajzenz's theory of planned behaviour are studied. Results of both studies supported the assumption that furnishing a goal intention with an additional implementation intention significantly increases the likelihood of actually performing the intended new behaviour. In the second study, the implementation intention intervention is combined with receiving a small vs higher monetary incentive. Receiving the higher incentive has similar behavioural effects to forming an implementation intention, whereas combining both interventions does not result in a stronger behavioural reaction. These results indicate that the behavioural effect of a higher monetary incentive might relay a similar volitional process to that of the implementation intention. Furthermore, in both studies there is some empirical evidence that both interventions suppress the impact of competitive habits.