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Impacts of Dynamic Optimization on ADA Paratransit Service Efficiency and Service Quality


Despite decades of experience with automated scheduling for paratransit services, true batch optimization (i.e., considering all trips at once) has only advanced as drivers move from paper-based schedules to app base schedules. Dynamic optimization requires the driver to be working with an App-based schedule that presents the driver with 1-2 hours of scheduled rides thereby allowing for last-minute schedule changes.

Several software vendors have developed different approaches to dynamic optimization and their different versions are now being implemented by scores of transit agencies in the US, Canada, and elsewhere.

There are two basic approaches to optimization. On-Demand and Pre-Book.

On-demand is where the riders generally communicate directly with the driver through an App, and schedule optimization is limited to short term direct application to the available fleet on the day of service. Pre-book optimization is applied to systems with large subscription demand where the system is susceptible to significant cancellation rates, and there is minimal daily contact with the rider. These systems remove rides on late running vehicles experiencing unexpected traffic congestion, accidents, breakdowns, etc.

For example, Green Bay Metro recently retained Via, a microtransit operator and technology vendor, to manage and operate Metro’s ADA paratransit service using both the pre-book and on-demand optimization products. Green Bay subsequently expanded Via’s role to use their on-demand product to improve ridership on underperforming fixed routes.

Full implementation of dynamic scheduling requires a ridership that is capable of communicating with the systems. Passengers who make booking mistakes reduce the effectiveness of these systems. A large contingent of senior passengers still prefer call centers bypassing the app-based alternatives.


The prospective benefits of dynamic dispatching include one or more of the following:

· Improved productivity and on-time performance

· Reduced cost of dispatch labor by reducing the number of dispatchers needed

· More focused dispatching on immediate chores, such as no-show requests

· A broadened and less expensive labor pool for prospective dispatchers (because the skill set required for proactive dispatching is no longer required)

· Increased efficiencies by linking ADA paratransit with microtransit services operated by ADA paratransit-certified drivers.

While these benefits are significant, the results have been inconsistent.

Research is required to better understand to what extent these prospective benefits are realized, and how transit agencies confront the hurdles in deploying the technology, and what unexpected service issues have materialized through its use.


This synthesis will be used to develop benchmarks and operation performance measures that define the experience in the industry from the perspective of the transit agencies, dispatchers, drivers and riders. Transit agencies can then decide for themselves what specific functionality yields the maximum benefits. This synthesis can also document the ways in which transit agencies have addressed the shortcomings and challenges that have manifested themselves in the tailoring, deployment and use of the dynamic optimization systems


Task 1: Meet with Panel and Manage Project

Task 2: Conduct a literature review/industry scan; summarize relevant information

Task 3: Prepare a draft survey questionnaire based on known dynamic application products capabilities

Task 4: Test the survey on select agencies

Task 3: Modify/Update survey questionnaire and conduct a targeted survey of transit agencies that adopted this practice (as identified from Task 2)

Task 4: Prepare a practice overview of best practices, policies and technologies used

Task 5: Submit case study candidates, rationales and interview guide to panel

Task 6: Conduct case studies

Task 7: Prepare and Submit First Draft Final Report

Task 8: Prepare and Submit Second Draft Final Report and Final Report


Documented best practices will have an immediate payoff for transit agencies looking to increase the efficiency of their ADA paratransit service.

Sponsoring Committee:AP055, Rural, Intercity Bus, and Specialized Transportation
Research Period:6 - 12 months
Research Priority:High
RNS Developer:Will Rodman
Source Info:The initial problem statement was developed as a result of AP055 efforts to consolidate relevant research needs pertinent to rural public transit, intercity bus, and/or paratransit from among 16 different source documents. The effort identified 175 different needs statements. This problem statement was one of about 10 research needs identified by the research to be pursue either as a synthesis or a full project. This particular problem statement was presented and discussed and refined based on input received during several video-conference meetings throughout the Fall. It was presented at the Full AP055 Committee and its Paratransit Committee in January 2021 at the TRB Annual Meeting and endorsed by both.
Date Posted:04/30/2021
Date Modified:05/28/2021
Index Terms:Quality of service, Paratransit services, Optimization, Mobile applications, Transit user applications, Schedules and scheduling,
Cosponsoring Committees: 
Public Transportation
Administration and Management
Data and Information Technology
Operations and Traffic Management

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