Built Environment, Causality and Travel

Abstract

Within research into influences of the built environment on travel behaviour, the issue of causality has gained increased attention. Several attempts have been made in order to identify the true effects of built environment characteristics by controlling for attitudinal and lifestyle factors and by applying more sophisticated techniques of analysis. Most research still suffers from insufficient theorizing and empirical investigation of causal mechanisms. An implicit conception of causality in terms of correlation between subsequent events appears to be widespread. This paper argues that such a conception of causality is inadequate and can lead to model specification error. Instead, a conception of causality as tendencies engendered by generative mechanisms is proposed. Based on such an understanding, the paper discusses in what sense the built environment can be said to exert causal influences on travel behaviour. In order to integrate knowledge about causal influences at the level of the individual and at the city level, a combination of qualitative and quantitative research methods is recommended.

Keywords:

• built environment
• correlations
• causality
• travel behaviour
• tendencies

Acknowledgments

The author would like to thank Sebastian Peters, Arvid Strand and Fitwi Wolday for valuable comments on a previous version of this paper. Thanks also to the anonymous reviewers of Transport Reviews for insightful and important comments.

Disclosure Statement

No potential conflict of interest was reported by the author.

Notes

1. Ontology is the philosophical study of the nature of being, becoming, existence, or reality, as well as the basic categories of being and their relations.

2. Critiques of understandings of causality prevailing among planning academics are given in separate papers (Næss, in press)

3. Hume held that human assumptions about causality resulted from constant conjunction of events, or customs based on expectations of subsequent events, rather than logic. His empiricist epistemological position rejects the possibility of knowledge about unobserved entities. Hume did not, however, consistently follow his original epistemological position, as he acknowledged that science had been effective in postulating successively deeper causal principles and mechanisms, such as gravity (Morgan, 2007).

4. To the extent that the issue of causality is at all discussed in research within the correlationist tradition, the problem of identifying a causal mechanism sometimes seems to be mixed up with the problem of estimating the strength of such a mechanism (see, for example, Van Wee and Boarnet 2014; Coevering et al., in press).

5. This also applies to several of my own earlier studies. In most of these studies I did, however, also include indirect effects of built environment characteristics via car ownership.

6. In the social sciences, agency is the capacity of an agent (a person or other entity) to act in the world.

7. Some other authors, such as Østerberg (1968), explicitly distinguish between social structures and material structures.