Validating Italian General Ecological Behaviour Questionnaire of Travellers Using Dichotomous Rasch Model

Ecological behaviour and its impact on the environment are subjects of public concern and understanding individual behavioural measures to induce sustainable lifestyles is of extreme importance for policy makers to assess and promote sustainable mobility. To this end, a questionnaire with highly reliable items, evaluations of determinants and accurate measurements of ecological behaviour is a precondition for understanding the levers of behavioural change. This paper aims at an understanding of whether the dichotomous Rasch model provides a legitimate measurement of General Ecological Behaviour (GEB) using a 26-item questionnaire as a valid tool to assess the pro-environment behaviour of a large sample of users. A web questionnaire was administered using the snowball sampling plan in the Piedmont region (Italy), with a sample of 4473 respondents. The results suggest that using the dichotomous Rasch model, the proposed questionnaire is able to effectively measure the pro-environment behaviour of travellers. Unidimensionality, the perfect level of item reliability of 1, the very high item separation of 34.22, the absence of larger differential item functions, and the local independence are all good indicators of a valid model. This research shows how a good, validated, and reliable measurement of ecological behaviour would support public bodies in planning environment-focused transport policies thanks to the knowledge of which variables determine pro-environment behaviour. In addition, the proposed approach also allows us to measure the efficacy of the adopted policies.