Transportation Research Part D: Transport and Environment
Spatial structure and mobility
Introduction
Spatial policy plays an important part in tackling the issues of mobility. Dutch government policy in this area, for example, is intended to achieve better spatial coordination of homes, places of work and other facilities. In this way the need to travel can be reduced and growth in car traffic lessened. The intention is also to reduce energy consumption. The Center for Energy Conservation, for example, has calculated that spatial planning can lead to energy savings of 17% in traffic and transport (Novem, 1997), which clearly also has a positive effect on the environment.
Although the government attaches great importance to structural spatial policy, only a fragmentary view of the effects of this policy can be seen, Handy (1992) concluded that instinctive assumptions about the impact of land use on mobility (particularly the idea that greater urban density leads to reduced car use and thus less energy consumption) are generally correct, but that the effect is not particularly great.
Many of these studies are based on highly aggregated spatial units in which different towns and cities are analyzed. These studies explain the collective travel patterns of all households in specific areas, some of which also include information about the social-economic characteristics of the population in the area. A great deal of attention has been devoted to the impact of spatial density and mixed land-use. Recently, more studies have been carried out at an individual level, in which the travel patterns of the inhabitants of a small number of neighborhoods were compared with each other (Cervero and Kockelman, 1997, Cervero and Radish, 1996). These analyses included corrections for personal and household characteristics. It was investigated to what extent certain spatial features of neighborhoods provide an explanation for mobility. These studies also showed that spatial planning has little impact.
This paper builds on this literature. We have investigated to what extent the spatial structure and planning of the residential environment provide an explanation for travel patterns and what urban planning and traffic management aspects play a significant part in this. It has also been considered to what extent policy aimed at spatial planning of the residential environment can contribute to reducing the need for mobility in general and car use in particular. This paper differs in several respects with regard to the foregoing literature. Firstly, very detailed data were available about the spatial characteristics of the homes of the respondents and the local environment. We did not use a number of aggregated characteristics of the spatial situation. Secondly, several traffic management and urban planning aspects were investigated and we did not limit ourselves to a small number of known spatial variables. Thirdly, part of the random sample consisted of a panel that meant that changes in the spatial situation of people who did not move house, as well as the situation of those who did, could be included. This type of data allowed us to establish links between changes in the spatial environment and changes in mobility. Finally, we used a national random sample. The data used in the study are therefore not related to a small number of areas, so that any variation or covariation in the spatial characteristics considered is much greater than that in many other studies.
Section snippets
Conceptual model
This study is essentially about people's mobility in relation to where they live. This mobility is described in terms of the number of trips they make on a weekly base, broken down into mode of transport and reason for the trip. The mobility of people and households arises from their need to take part in activities that are spatially distributed. Mobility is therefore a secondary matter, influenced by several important elements:
(a) Life styles. Personal characteristics and characteristics of
Data
To obtain a greater understanding of the effect of spatial characteristics on mobility, a study was set up in which the relationship between the mobility variables, on the one hand, and spatial, personal and household characteristics, on the other, could be investigated at the level of individual respondents. This effect was investigated through the use of regression analyses.
In the study, conducted in 1999, respondents were approached who had taken part in the Tijdsbestedingsonderzoek (TBO,
Explanatory power of spatial characteristics
Here we will consider to what extent various different determinants of mobility have an explanatory value. These were broken down into the spatial characteristics of the home and its environment, the location of the neighborhood (urban, suburban, village or rural) and social-economic and demographic characteristics of the respondents.
Using a cross-section regression analysis of all the data collected for 1999, it was determined to what extent these three different variables could explain the
Effect of spatial characteristics
Firstly, based on a cross-section analysis of the data available for all respondents for 1999, several regression models were considered which showed the links between the number of trips, on the one hand, and people's spatial, personal and household characteristics, on the other. These were models in which mobility could be analyzed in terms of the spatial characteristics in question without including a correction for personal and household characteristics. These models represent the gross
Dynamic analysis of spatial planning
Apart from the cross-section analyses discussed above, dynamic analyses could also be carried out using the data to investigate the extent to which changes in spatial characteristics led to changes in mobility patterns. At the same time it was checked whether people's personal characteristics had changed.
Simulation study
In this section we will consider how mobility would be affected by a number of hypothetically defined neighborhoods with consistent characteristics. The results presented in the previous sections demonstrate that no single characteristic is dominant. In order to assess the effects of residential area characteristics many aspects have to be taken into account simultaneously. Hence, we constructed a number of spatial scenarios. The cross-section models were used for the calculations. The
Conclusions
The aim of this paper was to obtain a better understanding of the extent to which spatial structure and spatial planning of the residential environment offer an explanation for mobility in general and the choice of mode of transport in particular, and what urban planning and traffic management aspects play an important role in this. In addition, it was investigated to what extent changes in the residential environment due to changes in neighborhoods or moving house produced effects that might
Acknowledgements
The study was commissioned by Connekt in Delft. The authors appreciate the enthusiastic project leadership by Rianne Zandee. In addition, stimulating comments were received from Albert Jansen (NOVEM) and Bert van Wee (RIVM). Furthermore, we thank Harry Timmermans, Martin Dijst and Tim Schwanen for their comments on the draft paper. Of course, any errors are our responsibility.
References (10)
- et al.
Travel choices in pedestrian versus automobile oriented neighborhoods
Transp. Policy
(1996) - et al.
Can land-use policy really affect travel behaviour?: A study of the link between non-work travel and land-use characteristics
Urban Studies
(1998) - et al.
Travel demand and the three Ds: Density. Diversity and Design, working paper
(1997) - Dijst, M.J., van Vossen, E., 1996. Woonlocatie en mobiliteit, een voorstudie inzake de nota Ruimte voor wonen,...
- Handy, S., 1992. How Land Use Patterns Affect Travel Patterns: a Bibliography. Council of Planning Librarians,...
Cited by (116)
Does built environment matter in a medium-sized African city? Empirical evidence from the interaction between land use and travel behavior
2023, Transportation Research Interdisciplinary PerspectivesWhat drives tourists to adopt self-driving cars?
2022, Transportation Research Part F: Traffic Psychology and BehaviourCauses and effects between attitudes, the built environment and car kilometres: A longitudinal analysis
2021, Journal of Transport GeographyStudy design impacts on built environment and transit use research
2020, Journal of Transport Geography