Out of a total of 159 dwellings, duplicated by chance in the 1962 and 1971 reading travel surveys, 80 were found to have been occupied by essentially the same households. This has allowed an exploratory study to be made of the effect of ageing on household composition, car ownership and trip generation in comparison with changes in general. For example, households which did not move house between the surveys were larger than average in 1962 but had reduced to average size by 1971. Households which did move tended to be replaced by larger households. In both cases, average trip rates were in good agreement with the full survey values when categorised according to the type of household. Moreover, the rate of change of trip rate with household size between 1962 and 1971 was similar to the cross-sectional values observed in each survey year. Statistical tests, where practicable, showed that the results could be generalised to the survey area as a whole. From the wide variety of new information obtained on topics such as household formation and life cycle changes, in addition to trip generation, it was concluded that duplicate survey data have considerable value to those engaged in the planning of housing, transport and perhaps land use as well. A simplified procedure was developed for estimating the likely number of duplicate households in second surveys. (Author/publisher)
Abstract