IDENTIFYING RESPONSE BIAS IN STATED PREFERENCE SURVEYS: ATTITUDINAL INFLUENCES IN EMISSIONS CHARGING AND VEHICLE SELECTION

摘要

Many of the environmental problems that are both real and sensitive community issues stemfrom the use of transport infrastructure by passenger and freight vehicles, which are not only asource of congestion, but a source of local pollutants such as lead, carbon monoxide and noise.While there has been extensive literature on the concept of congestion charging and theeconomic arguments have been known for decades, there have been very few studies that exploreroad pricing as a function of vehicle emissions. Moreover, a growing global focus onenvironmental concerns, in particular the role of carbon emissions in global warming, hascreated a social atmosphere where attitudes towards the environment are a pre-eminent focus ofnews media. In stated choice experiments, such attitudes play a key role in determiningwillingness to pay measures. This paper employs a stated preference survey to examine motorvehicle purchasing. In the survey, respondents were asked to choose between different motorvehicles in the presence of hypothetical annual and variable emissions surcharges. Using latentclass modelling, it is shown that four classes of individuals exist, whose sensitivities to annualand variable emissions surcharging differs. Importantly it is also shown that these differences canbe explained by environmental attitudes.