The Changing Allocation of Activities in Space and Time by the Use of ICT – "Fragmentation" as a New Concept and Empirical Results

Kurzfassung

The starting point of much theoretical and empirical research about the impact of information and communication technologies (ICT) on transport is the explicit or implicit hypothesis that ICT use leads to a reorganization of activities in time and space. Some relatively simple models have been developed to define the direction of impacts – substitution, complementarity, modification or neutrality – thus altering the demand for transport. In many cases, cost reduction and utility have served as the explanation for the transport relevant use of ICT (e.g. Salomon 1986, Luley/Bitzer/Lenz 2002). Recent discussions have emphasized the complexity of impacts that ICT may have on travel. Research has started to investigate not only the direct impacts of ICT on travel, but also the preceding process which is the modification of activities. As quite stimulating among the emerging activity based approaches turns out the fragmentation concept that was put forward above all by Helen Couclelis (for an overview on contributions on activity based approaches published in English see Mokhtarian/Salomon 2000). Starting from the general hypothesis that the fragmentation of activities augments transport demand, the concept explores the mechanisms that produce effects on travel. With reference to time geography, the fragmentation concept additionally provides some first starting points for a closer link of ICT and travel related processes to the general development in the economic, societal and political sphere. This concern is not a new one, as it was already expressed by Salomon in several contributions during the 1980s (cf. e.g. Salomon 1986). However, it was often lost out of sight. While concepts are developed to understand the complex impact of ICT on travel, problems as to their operationalisation in empirical research are rising. This concerns especially the registration of potential changes over a longer time period, and the separation of ICT related effects from effects that occur independently from ICT. Against this background – conceptual development and little empirical evidence – the present contribution focuses on the discussion of the fragmentation concept trying to advance it both theoretically and empirically. On the theoretical level, we explore the question why individuals should “fragment” their activities. In the empirical section we use a data set of the DLR-Institute of Transport Research, raised by a representative study about activities, ICT use and travel behavior in Germany in the year 2003. While the study has been planned as a panel, we currently hold data only from the first wave. As a consequence, we are not able to trace temporal changes. Instead, our evaluation of the data is concerned with the problem, how far an activity like work, which is particularly apt for fragmentation, shows signs of temporal and spatial disaggregation. With the help of a cluster analysis we identify groups with different “fragmentation behavior”. In a second step we analyze, if a statistically significant relation exists between fragmentation behavior and ICT use. In doing so our research is not primarily focused on any direct evaluation of the impact that ICT use has on travel, but on its impact on the performance of activities by different behavioral groups. The link to travel behavior is made by examining mode choices for different purposes and travel related attitudes.