Abstract As accessibility becomes an increasingly relevant concept in the analysis of sustainable transport and urban development, the accuracy of accessibility measures becomes increasingly vital. While more complex measures are gradually gaining popularity with increasing data and computational resources, policy makers and planners are still prone to opt for less complex methods that are easy to use and interpret. The cumulative opportunities measure is the most widely applied accessibility measure in planning practice, but it is also among the least accurate due to its lack of consideration of the impact of competition for those opportunities. This study seeks to highlight the impact of addressing competition for different urban services in the cumulative opportunities measure. A competition component is added to the measure, which is applied to a case study of three types of urban services in the Perth metropolitan area; jobs, primary/secondary education and shopping. The results show that considering competition changes the spatial patterns of accessibility and its equity. Since this approach reveals demand-supply imbalances, it can more accurately determine spatial inequalities in accessibility, and hence increases the utility of the cumulative opportunities measure. We also find that the three services had varying levels and spatial patterns of accessibility and spatial equity, thus relying on any single one of them for assessing spatial structural performance can be misleading.

中文翻译：

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使用累积机会度量衡量竞争中城市服务的可达性和空间公平性

摘要 随着可达性成为可持续交通和城市发展分析中越来越相关的概念，可达性措施的准确性变得越来越重要。虽然随着数据和计算资源的增加，更复杂的措施逐渐受到欢迎，但政策制定者和规划者仍然倾向于选择易于使用和解释的不太复杂的方法。累积机会度量是规划实践中应用最广泛的可达性度量，但由于缺乏考虑竞争对这些机会的影响，它也是最不准确的度量之一。本研究旨在强调在累积机会测量中解决不同城市服务竞争的影响。将竞争组件添加到度量中，应用于珀斯都会区三类城市服务的案例研究；工作、小学/中学教育和购物。结果表明，考虑竞争改变了可达性及其公平性的空间格局。由于这种方法揭示了供需失衡，它可以更准确地确定可达性的空间不平等，从而增加累积机会度量的效用。我们还发现，这三项服务在可达性和空间公平性方面具有不同的水平和空间模式，因此依赖其中任何一项来评估空间结构性能可能会产生误导。结果表明，考虑竞争改变了可达性及其公平性的空间格局。由于这种方法揭示了供需失衡，它可以更准确地确定可达性的空间不平等，从而增加累积机会度量的效用。我们还发现，这三项服务在可达性和空间公平性方面具有不同的水平和空间模式，因此依赖其中任何一项来评估空间结构性能可能会产生误导。结果表明，考虑竞争改变了可达性及其公平性的空间格局。由于这种方法揭示了供需失衡，它可以更准确地确定可达性的空间不平等，从而增加累积机会度量的效用。我们还发现，这三项服务在可达性和空间公平性方面具有不同的水平和空间模式，因此依赖其中任何一项来评估空间结构性能可能会产生误导。