Vol 16 No 2 (2016)
2016-04-01
Vol 16 No 2 (2016)
2016-04-01
Articles
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Accessibility is a key concept in both transport and urban planning. The key aims of transport policies, not only at the urban level but also at the supra-national (for example, European Union), national and regional level, are to improve accessibility. Accessibility is also a key concept that has become central to physical planning and in spatial modelling for more than fifty years. As measure of the relative nearness or proximity of one place and persons to all other places or persons, conceptually linked to Newton’s law of gravity, its origins can be traced back to the 1920s when it was used in location theory and regional economic planning (Batty, 2009). In his classic paper ‘How Accessibility Shapes Land Use’, Hansen (1959) was the first to define accessibility as a potential of opportunities for interaction and applied the concept to forecast employment developments in Washington D.C.. Accessibility is thus a key concept in planning and research but often a confusing one. Many different accessibility definitions and operationalisations in accessibility models and instruments have in the past decades been developed and applied by researchers from several academic fields (e.g., urban geography, rural geography, health geography, time geography, spatial economics, transport engineering) and transport and urban planners (e.g., see for reviews Geurs and van Wee, 2004; Páez et al., 2012; Papa et al., 2016).
Accessibility is a key concept in both transport and urban planning. The key aims of transport policies, not only at the urban level but also at the supra-national (for example, European Union), national and regional level, are to improve accessibility. Accessibility is also a key concept that has become central to physical planning and in spatial modelling for more than fifty years. As measure of the relative nearness or proximity of one place and persons to all other places or persons, conceptually linked to Newton’s law of gravity, its origins can be traced back to the 1920s when it was used in location theory and regional economic planning (Batty, 2009). In his classic paper ‘How Accessibility Shapes Land Use’, Hansen (1959) was the first to define accessibility as a potential of opportunities for interaction and applied the concept to forecast employment developments in Washington D.C.. Accessibility is thus a key concept in planning and research but often a confusing...
Accessibility is a key concept in both transport and urban planning. The key aims of transport policies, not only at the urban level but also at the supra-national (for example, European Union), national and regional level, are to improve accessibility. Accessibility is also a key concept that...
Karst T. Geurs, John Östh -
Internal travel distances are fundamental in accessibility measurement, as they affect the weight of the intra-regional interactions, especially when using a gravity formulation. The contribution of the internal accessibility of each zone to its overall accessibility is known as self-potential. Several studies demonstrate its importance in accessibility analyses, especially in the most urbanized regions. It is precisely in urban regions where internal travel distances are more difficult to estimate due to congestion, which in turn may be influenced by factors such as urban density, urban morphology, network infrastructure, etc. Accessibility analyses usually use coarse estimates of internal distances, generally based on the regions' area and in some cases considering its level of urbanization. In this study we explore different forms of estimating internal travel distances in accessibility analysis and reflect on their advantages and drawbacks. One of the main difficulties that arise when measuring internal travel distances is the lack of data. However, the growing potential of ICTs in providing new sources of data can be used to improve representativeness of data. In this study we used speed profiles data from TeleAtlas/TomTom to calculate internal travel distances for European NUTS-3 regions and we compare this measure with three other metrics traditionally used in the literature. Following this exercise, we discuss the conditions under which it is advantageous to use more complex measures of internal travel distance. Finally, we test the sensitivity of potential accessibility indicators to the combined effect of different internal distance metrics and distance decay factors.
Internal travel distances are fundamental in accessibility measurement, as they affect the weight of the intra-regional interactions, especially when using a gravity formulation. The contribution of the internal accessibility of each zone to its overall accessibility is known as self-potential. Several studies demonstrate its importance in accessibility analyses, especially in the most urbanized regions. It is precisely in urban regions where internal travel distances are more difficult to estimate due to congestion, which in turn may be influenced by factors such as urban density, urban morphology, network infrastructure, etc. Accessibility analyses usually use coarse estimates of internal distances, generally based on the regions' area and in some cases considering its level of urbanization. In this study we explore different forms of estimating internal travel distances in accessibility analysis and reflect on their advantages and drawbacks. One of the main difficulties that...
Internal travel distances are fundamental in accessibility measurement, as they affect the weight of the intra-regional interactions, especially when using a gravity formulation. The contribution of the internal accessibility of each zone to its overall accessibility is known as...
Ana Margarida Condeço Melhorado, Hande Demirel, Mert Kompil, Elena Navajas, Panayotis Christidis -
The interest in disentangling the role of borders in international trade is growing even within virtually borderless areas like the European Union. While there are a variety of research studies measuring how borders affect trade, there is little insight into the impact of borders on the potential accessibility to markets. The aim of this paper is twofold. First we provide a coherent calibration of the impedance parameters affecting trade (border effect based on best official data available and with a sound estimation of distance and the distance decay parameter with the use of network-based measurements). The second objective is to ascertain to what extent the market potential of different countries is hampered by the border effect. The analysis reveals that calibrating distance decay and considering border effects provides more realistic results. These results evidence that peripheral areas are more sensitive to the estimation of the distance decay parameter, whilst the main metropolitan regions are less affected by both distance decay and border effects. Finally, we present the decomposed market potential in a spillover-like matrix showing those countries that have a diversified set of contributors to their market potential and those where the number of contributors is limited.
The interest in disentangling the role of borders in international trade is growing even within virtually borderless areas like the European Union. While there are a variety of research studies measuring how borders affect trade, there is little insight into the impact of borders on the potential accessibility to markets. The aim of this paper is twofold. First we provide a coherent calibration of the impedance parameters affecting trade (border effect based on best official data available and with a sound estimation of distance and the distance decay parameter with the use of network-based measurements). The second objective is to ascertain to what extent the market potential of different countries is hampered by the border effect. The analysis reveals that calibrating distance decay and considering border effects provides more realistic results. These results evidence that peripheral areas are more sensitive to the estimation of the distance decay parameter, whilst the main...
The interest in disentangling the role of borders in international trade is growing even within virtually borderless areas like the European Union. While there are a variety of research studies measuring how borders affect trade, there is little insight into the impact of borders on the...
María Henar Salas-Olmedo, Patricia García-Alonso, Javier Gutiérrez -
In this paper we explore and compare various techniques for the calculation of distance decay parameters which are estimated using statistical methods with half-life decay parameters which are derived mathematically. Half-life models appear to be a valid alternative to traditional spatial interaction models, especially in the presence of spatially highly disaggregate data. Our results indicate that Half-life models are more accurate for the construction of decay parameters than are unconstrained spatial interaction models in ‘medium’ sized datasets but not as accurate as doubly-constrained models. However, using highly detailed and disaggregate datasets Half-life models may be viable alternatives to doubly-constrained spatial interaction models as the latter will be difficult to estimate when the number of origins and destinations increase. In addition, Half-life models rise in accuracy with increasing degrees of disaggregation due to reductions of systematic errors between observed individual level commuting distance and modelled distances between origins and destinations. In sum, our findings are as follows. First, since unconstrained and doubly-constrained spatial interaction models become increasingly difficult to estimate and/or less accurate to use compared to Half-life models as the spatial disaggregation increases choice of decay parameter estimation model should be considered in relation to level of disaggregation. Secondly, Half-life models are not affected by the systematic errors observed in the statistically derived models. Finally, using Half-life models for the estimation of decay parameters is simple which may make it easy to employ among practitioners lacking skills or computer means for the estimation of more complex statistically derived models.
In this paper we explore and compare various techniques for the calculation of distance decay parameters which are estimated using statistical methods with half-life decay parameters which are derived mathematically. Half-life models appear to be a valid alternative to traditional spatial interaction models, especially in the presence of spatially highly disaggregate data. Our results indicate that Half-life models are more accurate for the construction of decay parameters than are unconstrained spatial interaction models in ‘medium’ sized datasets but not as accurate as doubly-constrained models. However, using highly detailed and disaggregate datasets Half-life models may be viable alternatives to doubly-constrained spatial interaction models as the latter will be difficult to estimate when the number of origins and destinations increase. In addition, Half-life models rise in accuracy with increasing degrees of disaggregation due to reductions of systematic errors between...
In this paper we explore and compare various techniques for the calculation of distance decay parameters which are estimated using statistical methods with half-life decay parameters which are derived mathematically. Half-life models appear to be a valid alternative to traditional spatial...
John Östh, Johan Lyhagen, Aura Reggiani -
This paper focuses on the spatial influence of High-Speed Rail stations, based on the notion of catchment area. Given the features of High-Speed Rail, its operations can and must serve a role beyond the station and the city in which it is located. Using a spatial systemic approach, this paper proposes a method to analyse the factors that may affect the size and shape of the catchment areas according to the relationship between distance and ridership. This study employs data from surveys of six stations of the Spanish high-speed rail system to apply the model and demonstrates that the context is crucial for regional use. The outcome also proves that other relevant factors should be considered in addition to the network to extend the use of highspeed services and increase its profits, which is a potential approach for future research.
This paper focuses on the spatial influence of High-Speed Rail stations, based on the notion of catchment area. Given the features of High-Speed Rail, its operations can and must serve a role beyond the station and the city in which it is located. Using a spatial systemic approach, this paper proposes a method to analyse the factors that may affect the size and shape of the catchment areas according to the relationship between distance and ridership. This study employs data from surveys of six stations of the Spanish high-speed rail system to apply the model and demonstrates that the context is crucial for regional use. The outcome also proves that other relevant factors should be considered in addition to the network to extend the use of highspeed services and increase its profits, which is a potential approach for future research.
This paper focuses on the spatial influence of High-Speed Rail stations, based on the notion of catchment area. Given the features of High-Speed Rail, its operations can and must serve a role beyond the station and the city in which it is located. Using a spatial systemic approach, this paper...
Héctor S. Martínez, Amparo Moyano, José M Coronado, Maddi Garmendia -
This paper examines the role of perceptions and attitudes in railway station accessibility. We add unobserved (latent) variables to the Generalised Transport Access Cost (GTAC) of cycling to Dutch railway stations in the metropolitan area of The Hague – Rotterdam. A hybrid discrete choice model was estimated for access mode and two latent variables which were obtained through factor analysis: perception of station environment (including factors such as the users’ judgement of the station, assessment of travel information, presence of high speed trains) and perceived connectivity (including factor such as the evaluation of punctuality and the frequency of the train and quality of bicycle infrastructure). The estimated individual utility was applied to a station access cost index. A comparison between standard logit and hybrid utility functions identifies improvements in the utility-based measures by using discrete choice models. Utilities are computed by station departure, postcode of residence and neighbourhood. The results show, first, that omitting unobserved effect in utility-based measures tends to lead to overestimations of the accessibility levels. Secondly, different variations in accessibility levels are revealed, by size of railway stations and urban areas. Finally, the results highlight stronger effects of network connectivity impedances than station environmental impedances in generalised transport costs.
This paper examines the role of perceptions and attitudes in railway station accessibility. We add unobserved (latent) variables to the Generalised Transport Access Cost (GTAC) of cycling to Dutch railway stations in the metropolitan area of The Hague – Rotterdam. A hybrid discrete choice model was estimated for access mode and two latent variables which were obtained through factor analysis: perception of station environment (including factors such as the users’ judgement of the station, assessment of travel information, presence of high speed trains) and perceived connectivity (including factor such as the evaluation of punctuality and the frequency of the train and quality of bicycle infrastructure). The estimated individual utility was applied to a station access cost index. A comparison between standard logit and hybrid utility functions identifies improvements in the utility-based measures by using discrete choice models. Utilities are computed by station departure,...
This paper examines the role of perceptions and attitudes in railway station accessibility. We add unobserved (latent) variables to the Generalised Transport Access Cost (GTAC) of cycling to Dutch railway stations in the metropolitan area of The Hague – Rotterdam. A hybrid discrete choice...
Lissy La Paix Puello, Karst T. Geurs -
Although there has been a significant focus on evaluating accessibility to facilities, the differences between age groups and/or mode of access to train stations is less clear. This paper compares perceived and measured accessibility to train stations among three age groups: young adults (18-24), middle aged adults (25-59) and elderly adults (60+) and three travel modes, Park and Ride (PnR), Bus and Ride (BnR) and Walk and Ride (WnR). The study focuses on the Greenwood railway station, Perth, Australia. Measured accessibility was lower than perceived accessibility for all three age groups. Both perceived and measured accessibility to train stations were lower for the elderly than the other groups. The catchment area of elderly PnR users was also the smallest. Middle aged adults evaluated accessibility (perceived) by WnR the highest. Young adults were found to have a larger PnR catchment area than other groups. Inadequate accessibility to Greenwood Station for different age groups and by different travel modes were identified, which can be used as a decision-making aid by practitioners and station managers for improving accessibility for these cohorts. The techniques used are directly transferable to the study of other stations.
Although there has been a significant focus on evaluating accessibility to facilities, the differences between age groups and/or mode of access to train stations is less clear. This paper compares perceived and measured accessibility to train stations among three age groups: young adults (18-24), middle aged adults (25-59) and elderly adults (60+) and three travel modes, Park and Ride (PnR), Bus and Ride (BnR) and Walk and Ride (WnR). The study focuses on the Greenwood railway station, Perth, Australia. Measured accessibility was lower than perceived accessibility for all three age groups. Both perceived and measured accessibility to train stations were lower for the elderly than the other groups. The catchment area of elderly PnR users was also the smallest. Middle aged adults evaluated accessibility (perceived) by WnR the highest. Young adults were found to have a larger PnR catchment area than other groups. Inadequate accessibility to Greenwood Station for different age groups...
Although there has been a significant focus on evaluating accessibility to facilities, the differences between age groups and/or mode of access to train stations is less clear. This paper compares perceived and measured accessibility to train stations among three age groups: young adults...
Mark Ryan, Ting (Grace) Lin, Jianhong (Cecilia) Xia, Todd Robinson