Measuring the impacts of new public transit services on space-time accessibility

Lee, J. and Miller, H. J. (2018) “Measuring the impacts of new public transit services on space-time accessibility: An analysis of transit system redesign and new bus rapid transit in Columbus, Ohio, USA,” Applied Geography, 93, 47-63.


  • Lack of access to opportunities contributes to poor social and health outcomes.
  • Columbus, OH introduced a transit route and schedule redesign and bus rapid transit.
  • We analyze impacts on accessibility to opportunities in a deprived neighborhood.
  • Detailed route and schedule data allow high resolution accessibility analysis.
  • The new bus rapid transit has a much greater impact on accessibility


The absence of effective access to opportunities and services is a key contributor to poor socio-economic and health outcomes in underserved neighborhoods in many cities. The city of Columbus, Ohio, USA is attempting to enhance residents’ accessibility by providing new public transit services. These new services include a major Transit System Redesign (TSR) of the conventional bus network and the introduction of a new bus rapid transit, named CMAX. Using a high-resolution space-time accessibility measure, we analyze whether these new public transit services will change residents’ accessibility to job and healthcare in an underserved neighborhood of Columbus. Also, we assess whether enhancing the CMAX service to reduce delays (e.g., reserved lane, off-board payment system) will improve accessibility. The high-resolution space-time accessibility measure in this study uses published public transit schedules via the General Transit Feed Specification (GTFS). We use multiple departure times during a day to account for the temporal fluctuations of accessibility based on the transit schedule changes. We also consider the operating hours of job opportunities and healthcare services. Results suggest that the TSR yields ambiguous benefits for accessibility to jobs and healthcare. However, the new CMAX service and its potential upgrades lead to a substantial increase in both job and healthcare accessibility. The results can be used for city officials and urban planners to evaluate the effectiveness of public transit innovations in improving accessibility.

Keywords: Transportation; Space-time accessibility; Public transit; Bus rapid transit; Jobs; Healthcare

Space-time data science for a speedy world

Miller, H.J. (2015) “Space-time data science for a speedy world,I/S: A Journal of Law and Policy for the Information Society, 10, 705-720.

Abstract: Space-adjusting technologies such as transportation and information/communication technologies are accelerating our world in complex ways. A speedy world has benefits but also challenges attempts to make it more sustainable and resilient. Our capabilities for observing human dynamics have improved dramatically, but less well developed are capabilities for extracting relevant space-time knowledge and making decisions while that knowledge is still fresh. This paper reviews the challenges and issues involved in developing space-time data science to deliver actionable knowledge quickly in a speedy world.

Access without ownership: Mobility as a service

A transport engineer in Helsinki is pioneering the real-world implementation of on-demand mobility services.  [A 24-Year-Old Transport Engineer Is About To Free Her City From Car Ownership.]

Sonja Heikkilä wants to create a sustainable mobility service ecosystem where Helsinki citizens can configure mobility services from a wide range of providers – public, private and shared – via smartphone apps.  In the future, users may be able to purchase monthly mobility plans that are tailored to their activity patterns and needs,  much like current mobile phone voice + data plans.

Helsinki is demonstrating that you can have access without ownership.  The average automobile is stationary and parked for 95% of its existence – a tremendously inefficient use of a valuable mobility resource.  Ownership also leads to overuse and binge mobility.

Social media, location-based services (LBS) and smart cities can help facilitate transportation polycultures that are not only more efficient but more effective and sustainable.  We must use these technologies to cultivate mobility services and collaborative mobility rather than the fight the futile battle of easing congestion through expanding roads and highways.  It has never worked, and it never will.