Spatial accessibility, commuters and spatial development

这项研究的重点是确定自1970年以来通勤行为的结构性变化作为空间可达性和人口重新分布动态的函数。该项目旨在检验从文献中得出的三个假设：a)郊区边缘已经与各自的核心城市脱钩，郊区的这种成熟导致通勤距离缩短；b)高密度居民点与低通勤量(即从家到工作的距离更短)相关，即使将来往和外出的出行结合在一起考虑也是如此；c)通达性的进一步改善对通勤行为的影响随着时间的推移明显下降。通过对德国和瑞士的比较，可以确定不同空间规划和交通规划战略的效果。到目前为止，已经提出了几个假设：通过瑞士每个城市的通勤地区来分析通勤联系日益复杂的问题。在德国的四个案例研究中，没有检测到除了郊区化过程之外通勤距离的减少。在方法论方面，对于假设a)开发了一种新的程序，可以自动识别重叠的集水区；b)开发了新的程序来分配始发地和目的地的运输量，从而可以用空间统计方法来解释运输量。在未来的研究中，可以用于c)的模式选择和目的地选择的通常离散模型必须扩展，以便捕捉空间相关性的可能影响。

The focus of this research is the identification of the structural changes in commuting behaviour since 1970 as a function of the dynamics of spatial accessibility and population redistribution. The project aims to test three hypotheses derived from the literature: a) that the suburban fringes have decoupled from their respective core cities and that this maturation of suburbia leads to a reduction in commuting distances; b) that high-density settlements are associated with low commuting volumes (i.e. shorter home to work distances) even when incoming and outgoing trips are considered jointly; c) that the effect of further improvements in accessibility on commuter behaviour has declined markedly over time. The comparison between Germany and Switzerland allows for an identification of the effects of different spatial planning and transport planning strategies.Several hypotheses have been worked out so far: The increasing complexity of commuting linkage has been analysed by the mean of commuting regions of each municipality in Switzerland. In four case studies of Germany, reducing of commuting distance beside a suburbanisation process has not been detected.In terms of methodology, for hypothesis a) a new procedure has been developed that can automatically identify overlapping catchment areas b) new procedures for allocating transport volume to origin and destination are developed so that transport volume can then be explained with methodologies of spatial statistics. In future research the usual discrete models of mode choice and destination choice that can be used for c) have to be expanded in order to catch possible effects of spatial correlation.