Comparison of Different Accessibility Measurements

Different types of accessibility measurements are hypothesized to produce different conclusions on levels of accessibility of parks. To develop a better understanding of the impact of choice of accessibility measurement, six types of accessibility measurements were calculated and compared in this chapter, covering Euclidean distance, Manhattan distance, Network distance, Minkowski distance, Gravity value, and perceived accessibility. Among these measurements, a context-specific Minkowski distance was developed to approximate actual walking distance. In addition, a context-specific distance decay curve and Gravity model were developed based on residents’ actual travelling data. Differences among different types of accessibility were statistically analyzed, both globally and locally. Accessibility level was also compared among four study sites, aiming to explore whether park provision influences park accessibility. Comparison between accessibility to most often used parks and nearest parks was also conducted, to investigate the influence of destination choice set on the measurement of accessibility. In addition, physical and perceived accessibility for residents who were surveyed at households and at parks were compared, to evaluate the influence of sampling process on accessibility measurement results. A comfortable walking distance range was also estimated in this study.