This thesis is motivated by the professional belief that planning and design decisions regarding lower scale levels may potentially contribute to a reduction of car mobility. In the literature and in practice, it is a commonly held belief that different urban shapes and transportation networks will induce different activity-travel patterns. Dutch spatial mobility policies and plans, especially formulated at the level of the neighbourhood, city district and city, are either explicitly or implicitly based on a number of largely untested assumptions. Although a vast amount of literature on the relationship between urban form and travel patterns has been published in the last decade, there are several reasons why their relevance is limited. First, most studies are from a non-Dutch or even non-European origin, raising the issue of spatial transferability of research findings. Given the differences between the Netherlands and other, especially non-European, countries in size, the spatial and cultural organisation of cities, and the relative absence of the bicycle in many other countries, further empirical investigation whether the results obtained in non-Dutch countries can be generalised to the Netherlands is required. Secondly, the existing studies show some serious potential methodological flaws. As Kitamura et al [1997] have argued “Is the observed association between travel and land use real, or is it an artifact of the association between land use and the multitude of demographic, socioeconomic, and transportation supply characteristics, which also are associated with travel? The aim of this thesis is therefore to empirically test the implicit or explicit car mobility reduction claims, underlying current Dutch mobility and land use policies. In particular, the objective is to examine whether a relationship between urban form and travel patterns exists in the Netherlands, and to explore the nature and strength of this relationship. The focus in this study will be on the neighbourhood/city district and the city. The urban form characteristics examined in this study include the morphology (urban shape) and transportation network types of the city and the neighbourhood, the relative location of neighbourhoods, the availability of facilities, and the density of the city and neighbourhoods. In line with recent conceptualisations in transportation research, travel and mobility patterns are viewed in the context of activity-travel patterns (see e.g., Ettema and Timmermans, 1997). Travel demand is derived from the activities that individuals and households need or wish to conduct. The urban environment offers opportunities to pursue these activities, but at the same time may constrain the conduct of activities. Hence, to better understand the complex and possibly indirect nature between urban form characteristics and activity-travel patterns, an activity-based approach was followed as it better allows disentangling the impact of various factors, including urban form, on mobility patterns. This thesis describes the results of an extensive study into the relationship between urban form characteristics of neighbourhoods and cities and activity-travel patterns in a Dutch context. The activity-based approach was adopted for this study. The design of the study and its results are reported in 8 chapters. The next two chapters deal with current planning practice and existing knowledge concerning the relationship between urban form and activity-travel patterns. Chapter 2 discusses past, present and future spatial mobility policies in the Netherlands and derives the principles underlying these policies. Chapter 3 outlines the literature on the relationship between urban form and activity-travel patterns and derives potentially influential urban form characteristics. Chapter 4 presents the research design of this project. It elaborates the activity-based approach and discusses the conceptual framework underlying the study. Chapter 5 presents the operational decisions, underlying the data collection and the selection of explanatory variables. This is followed by a discussion of the process of data collection in more detail. The choice of cities and neighbourhoods, the design of the questionnaire that was administered, and the response that followed will be discussed. Furthermore, the explanatory variables selected to operationalise the concept of urban form will be outlined. The data include both characteristics of frequently made trips for specific purposes (work, shopping, et cetera) and a full two day activity-travel diary. Chapters 6 and 7 present the results of the data analysis. Chapter 6 deals with the analyses of a number of frequently made trips, while chapter 7 discusses the results of analyses of travel data from complete activity-travel diaries. Finally, in chapter 8, the major findings of this thesis will be summarised and discussed. (Author/publisher)
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