This research investigates the interactions among transit (public transport) modes by inferring complementarity from a comparison of access provided by various transit modal combinations over a period of 160 years. A unique historical dataset of transit networks and services including buses, trains, and trams, generated for the Greater Sydney region for a period spanning from 1855 to 2015 was used. Access to population was measured for each year by 11 different modal cases formed by combinations of the three transit modes at a spatially disaggregated level as well as the regional level. The changes in access provided by the different modal cases were compared temporally and spatially to infer complementarity among the modes. Throughout the study period, trains, buses, and trams (when available) were found to be highly sub-additive at the regional level. Spatial comparison of complementarity was also demonstrated for Sydney’s Central Business District as an example. Such an investigation of access by modal combinations is a useful planning tool to ensure equitable supply and to investigate transfer benefits and penalties.

本研究通过比较 160 年期间各种公交模式组合提供的通行方式来推断互补性，从而调查了公交（公共交通）模式之间的相互作用。使用了 1855 年至 2015 年为大悉尼地区生成的交通网络和服务（包括公共汽车、火车和有轨电车）的独特历史数据集。每年通过三种交通模式在空间分类级别和区域级别组合形成的 11 个不同模式案例来衡量人口访问。在时间和空间上比较不同模态情况提供的访问变化，以推断模式之间的互补性。在整个研究期间，发现火车、公共汽车和有轨电车（如果有）在区域层面具有高度的次级累加性。此外，还以悉尼中央商务区为例，展示了互补性的空间比较。这种通过模态组合对准入的调查是确保公平供应和调查转移收益和处罚的有用规划工具。