Do environmental concerns affect commuting choices? Hybrid choice modelling with household survey data
Jennifer Roberts, Gurleen Popli, Rosemary J. Harris
In order to meet their ambitious climate change goals governments around the world will need to encourage behaviour change as well as technological progress; and in particular they need to weaken our attachment to the private car. A prerequisite to designing effective policy is a thorough understanding of the factors that drive behaviours and decisions. In an effort to better understand how the public’s environmental attitudes affect their behaviours we estimate a hybrid choice model (HCM) for commuting mode choice using a large household survey data set. HCMs combine traditional discrete choice models with a structural equation model to integrate latent variables, such as attitudes and other psychological constructs, into the choice process. To date HCMs have been estimated on small bespoke data sets, beset with problems of sample selection, focusing effects and limited generalizability. To overcome these problems we demonstrate the feasibility of using this valuable modelling approach with nationally representative data. Our estimates suggest that environmental attitudes and behaviours are separable constructs, and both have an important influence on commute mode choice. These psychological factors can be exploited by governments looking to add to their climate change policy toolbox in an effort to change travel behaviours.