The influence of the impedance function on gravity-based pedestrian accessibility measures: A comparative analysis

Vale, David; Pereira, Mauro

doi:10.1177/0265813516641685

Cited by 30 publications

(25 citation statements)

References 61 publications

(85 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similar to Kwan (Kwan 1998) and Vale & Pereira (Vale and Pereira 2017), correlations in accessibility across measures are generally strong (Figure 3), indicating many capture similar spatial processes. For example, of those used in Figures 1 and 2, results from the negative exponential (EXP0_15), modified Gaussian (MGAUS180), cumulative rectangular (CUMR40), and cumulative linear (CUML40) measures of impedance all show correlation coefficients of at least 0.87.…”

Section: Transport Findingsmentioning

confidence: 89%

Accessibility Toolbox for R and ArcGIS

Higgins¹

2019

Transport Findings

View full text Add to dashboard Cite

Analyses of place-based accessibility undertaken in the popular ArcGIS environment require many time-consuming and tedious steps. Moreover, questions persist over the selection of an impedance function and cost or cut-off parameters. In response, this paper details a new Accessibility Toolbox for R and ArcGIS that includes a Python tool for conducting accessibility analyses and an interactive R Notebook that enables the visualization and customization of impedance functions and parameters. Using this toolbox, researchers and practitioners can simplify their accessibility analysis workflow and make better decisions about the specification and customization of travel impedance for their study context.

show abstract

Section: Transport Findingsmentioning

confidence: 89%

Accessibility Toolbox for R and ArcGIS

Higgins¹

2019

Transport Findings

View full text Add to dashboard Cite

show abstract

“…where i is a population center (i = 1,2,...I), I is the total number of the population centers, A si is the accessibility from the ith population center to the nearest RCF after optimization, a is the weighted average accessibility, V is the total number of beds of all RCFs, w i is the demands of the ith population center, namely the number of the elderly who need the service of RCFs, W is the total demands of all population centers. The commonly-used improved gravity-based method is used to calculate the accessibility as follows [28]:…”

Section: Maximizing Equitymentioning

confidence: 99%

Spatial Optimization of Residential Care Facility Configuration Based on the Integration of Modified Immune Algorithm and GIS: A Case Study of Jing’an District in Shanghai, China

Cheng

Cui

2020

IJERPH

View full text Add to dashboard Cite

As the population is aging rapidly, the irrationality of residential care facility (RCF) configuration has impacted the efficiency and quality of the aged care services so significantly that the optimization of RCF configuration is urgently required. A multi-objective spatial optimization model for the RCF configuration is developed by considering the demands of three stakeholders, including the government, the elderly, and the investor. A modified immune algorithm (MIA) is implemented to find the optimal solutions, and the geographic information system (GIS) is used to extract information on spatial relationships and visually display optimization results. Jing’an District, part of Shanghai, China, is analyzed as a case study to demonstrate the advantages of this integrated approach. The configuration rationality of existing residential care facilities (RCFs) is analyzed, and a detailed recommendation for optimization is proposed. The results indicate that the number of existing RCFs is deficient; the locations of some RCFs are unreasonable, and there is a large gap between the service supply of existing RCFs and the demands of the elderly. To fully meet the care demands of the elderly, 6 new facilities containing 1193 beds are needed to be added. In comparison with the optimization results of other algorithms, MIA is superior in terms of the calculation accuracy and convergence rate. Based on the integration of MIA and GIS, the quantity, locations, and scale of RCFs can be optimized simultaneously, effectively, and comprehensively. The optimization scheme has improved the equity and efficiency of RCF configuration, increased the profits of investors, and reduced the travel costs of the elderly. The proposed method and optimization results have reference value for policy-making and planning of RCFs as well as other public service facilities.

show abstract

“…A research question also remains: what is the best function of distance in gravity or potential models? In research to date, a cumulative Gaussian function has been considered as having the best fit for walking (Vale and Pereira, 2017).…”

Section: Theoretical Backgroundmentioning

confidence: 99%

Modelling walking accessibility: A case study of Ljubljana, Slovenia

Tiran

Lakner

Drobne

2019

Moravian Geographical Reports

View full text Add to dashboard Cite

Walkable access is recognised as one of the most important factors for deciding to walk instead of using other modes of transport. Distance has been less accurately taken into consideration in previous walking accessibility measures, however, as they are often based on an isotropic approach or on a fixed distance threshold. The objective of this paper is to present a method of modelling continuous walking accessibility to different amenities in a city, with an integrated network-based and distance-decay approach, applied to a case study of the city of Ljubljana, Slovenia. The approach is based on a web survey to obtain data on acceptable walking distances to different types of amenities. Several distance decay functions were analysed for each type of amenity from the cumulative frequency of responses. The best fitting functions were used to model the walking accessibility surfaces for individual amenities in the network, representing five domains (retail, services, recreation, education and transportation) and an overall walking accessibility index. Despite certain limitations and a further need to assess the validity of the methods, our distance-decay network-based approach is more accurate than the isotropic or even network-based modelling of walking distances in continuous or threshold approaches, as it enables the researcher to take into account the differences in propensities to walk to different amenities. The results can be used by city authorities and planners for implementing actions to improve walking accessibility in the most problematic areas.

show abstract

The influence of the impedance function on gravity-based pedestrian accessibility measures: A comparative analysis

Cited by 30 publications

References 61 publications

Accessibility Toolbox for R and ArcGIS

Accessibility Toolbox for R and ArcGIS

Spatial Optimization of Residential Care Facility Configuration Based on the Integration of Modified Immune Algorithm and GIS: A Case Study of Jing’an District in Shanghai, China

Modelling walking accessibility: A case study of Ljubljana, Slovenia

Contact Info

Product

Resources

About