317 / 2019-02-22 11:48:42

A systematic evaluation of accessibility measures by the two-step floating catchment area (2SFCA) methods

Accessibility, Spatial interaction model, 2SFCA

全体主题 > Land-use & Transportation modeling

The recent decade has witnessed a new wave of development in the place-based accessibility theory, revolving around the two-step floating catchment area (2SFCA) method. The 2SFCA method, initially serving to evaluate the spatial inequity of health care services, has been further applied to other urban planning and facility access issues. Among these applications, different distance decay functions have been incorporated in the thread of model development, but their applicability and limitations have not been fully examined. To this end, the paper has employed a place-based accessibility framework to compare the performance of twenty-four 2SFCA models in a comprehensive manner. Two important conclusions are drawn from this analysis: at a small analysis scale (e.g., citywide), the catchment size is the most critical model component; at a large analysis scale (statewide), the distance decay function is of elevated importance. In sum, this comparative study can provide the theoretical support necessary to applications and modifications of the 2SFCA models for various urban planning, service delivery, and spatial equity problems. Justification of the catchment size and calibration of the distance decay parameters through empirical evidence is needed in future accessibility assessments.