Explaining Reurbanization - Empirical Evidence of Intraregional Migration As a Long-term Mobility Decision from Germany
G Matthes, Hamburg University of Technology, DE
Analysing German panel data (SOEP), the question is focussed which individual motives and conditions influence the reurbanization process to in order to forecast its future development and to be able to find approaches to influence it.
In past decades, suburbanization has dominated the urban development in German city regions. Several consequences accompanied this development, such as social segregation, soil sealing or transport related impacts. Recently, several studies have revealed an incipient reurbanization in terms of Berg?s theory of metropolitan evolution (BERG et al 1982). Scientists presume that the reurbanization process interferes with the previous pattern of urban development. Some say that it may weaken suburbanization or might even be able to reverse it. Taking into account that the local population development depends increasingly on migration, as the German population has been shrinking and considering the spatial consequences of evident social changes, we expect that reurbanization gains in importance in the future (BMVBS, BBR 2007: 147). Furthermore it is likely that interventions increase in order to advance reurbanization as the notion evokes positive associations in the press and among practitioners of urban planning.
Although reurbanization may sound like ?healing? the urban system from the ?nuisances? of suburbanization automatically, we need to observe it critically; regarding e.g. social issues, growing spatial disparities are expected (BRECKNER et al. 1998: 121). The hypothesis of the our actually conducted study is that reurbanization bears potential to spread environmentally friendly ways of organizing daily mobility ? but that the chance of those positive effects might be given away if policy does not accompany the process adequately. The study discusses the hypothesis by treating the following three issues in order to deduce first planning approaches:
1. Assessing the actual importance and novelty of social-demographically and spatially differentiated reurbanization: What is the extent and recent temporal evolution of intra-regional migration patterns?
2. Explaining the phenomenon of reurbanization in order to forecast its future development and to be able to find approaches to influence it: What are the individual motives and conditions beyond the revealed migration-processes? Special attention is paid to the ring-to-core migrants, as the motives of core-to-ring migrants are well explored already.
3. Analysing changes of individual travel behaviour in order to work out potential reductions of the migrants? motorized passenger kilometres: How and why does the migrants? travel behaviour change and what role does the location choice play? Where are possible approaches for planning to intervene?
A preliminary study has been conducted to operationalise the term reurbanization, to treat key-aspects of all issues and to develop and test appropriate survey methods. Treatment of space in the context of travel-behaviour analysis is given special concern, by orienting the term ?city? at evident settlement structures, rather than at administrative city-frontiers (MATTHES 2010). In light of the results of this preliminary study, the proposed paper focuses foremost on the second question, namely we treat the question under which conditions a household decides to move or to stay. It might be that reurbanization is the result of many not-movers in the city-centres.
To examine factors influencing the relocation decision, household-data from the German socio-economic panel (SOEP) is analysed. The data includes the households? socio-economic characteristics, activities, dwellings, spatial surroundings etc. which can be evaluated in the context over 10.000 relocations. The data is enriched by information about the regional housing market and the city-regional location. In the analysis special attention is paid to spatial factors and household characteristics which are known to influence travel-behaviour. Descriptive and multivariate methods are used to answer the following questions:
1. Ring-to-core-migrants: What socio-economic and demographic characteristics do these households have?
2. All households, spatially and socio-economically segmented: Where is the respective threshold to decide whether to leave or not to leave the actual dwelling or quarter? What factors influence this decision in which way?
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Matthes, Reurbanisierung in Hamburg und ihre Auswirkungen auf die Verkehrsentwicklung. ECTL Working Paper 43, Hamburg, 2010
Association for European Transport