8: The Creation of Simulated Household Travel Survey Data Based on Available Demographic Data from Households

Household travel surveys (HTSs) are expensive to undertake, costing up to AU$300 per respondent in Australia, depending on the technique employed for data collection. Elsewhere around the world, similar high costs are being experienced. CATI surveys in the U.S. routinely cost around US$150 and up per completed household (Cambridge Systematics, 1996). Given the large sample sizes (2,000 to 3,000 households are considered a minimum prerequisite) required in order to capture representativeness of existing household types within both large and small metropolitan areas, the costs of HTSs soon become prohibitive to all but large, well funded government organisations. Yet, despite the absolute and relative costs, the data provided by HTSs are critical to travel-demand forecasts used to estimate the impact of proposed transport policies, as well as to determine regional travel characteristics. This is accomplished by the collection of household demographic and socio-economic data along with associated travel or activity data for each of the surveyed households that are in turn used to derive travel patterns for particular areas over a period of time.