Travel Behavior

Driver Memory: Motorist Selection and Retention of Individualized Headways in Highway Traffic

Cassidy, Michael J.
Windover, John R.
1998

The paper presents evidence that (1) drivers have different personalities in that they follow vehicles at different headways, and (2) drivers retain their personalities in that each driver tends to maintain his headway over space and, in some instances, drivers return to their headways after being forced by a traffic disturbance to alter them temporarily. This attribute, which we term driver memory, is revealed by visual inspection of modified curves of measured cumulative vehicle arrival number versus time.

Identification and Integration of Commercial Heavy Vehicle Retarders

Druzhinina, Maria
Moklegaard, Lasse
Stefanopoulou, Anna G.
2002

This report describes the development and experimental validation of a coordination scheme between friction and discretely variable compression brakes for a Class 8 Freightliner truck used as a development platform in the California PATH program. The coordination scheme that we developed maintains the speed tracking performance of the nominal PID controller which was originally designed by the UCLA team for the case of friction brakes only.....

Traffic Management System Performance Using Regression Analysis

Levinson, David
Chen, Wei
2006

This study can be viewed as a preliminary exploration of using regression analysis to evaluate long-run traffic management system performance. Four main traffic management systemsin the Twin Cities metro area --- Ramp Metering System, Variable Message Signs (VMS), Highway Helper Program, and High Occupancy Vehicle (HOV) System were evaluated based on multiple regression models. Link speed and incident rate were employed as the response variable separately. Consequently, regression analysis can be a simple and effective research method for testing the macroscopic association between traffic...

Testing Daganzo's Behavioral Theory for Multi-lane Freeway Traffic

Chung, Koohong
Cassidy, Michael
2002

This report describes the detailed, albeit still preliminary study of traffic on stretches of two different freeways. Both were plagued by merge bottlenecks. The first of these sites is the Gardiner Expressway, a 3.3 km long freeway stretch in Toronto, Canada. The site was selected because of its suitable geometry (i.e. its merge bottleneck) and its well-tuned loop detectors located upstream and downstream of the bottleneck. The site thus provided for an exceptionally good “laboratory” for testing Daganzo’s behavior theory of drivers (Daganzo, 1999). It turns out that the observations from...

Collisions in Freeway Traffic: Influence of Downstream Queues and Interim Means to Address Them

Li, Zhibin
Chung, Koohong
Cassidy, Michael J.
2013

Findings from previous studies indicate that a freeway traffic collision is more likely to occur in close physical proximity to the tail of a queue. The implication is that collision likelihood increases when drivers abruptly alter their trajectories (e.g., by decelerating or changing lanes) on encountering the queue. The implication is supported and bolstered with new and detailed data that were painstakingly extracted from two freeway stretches in California. These data show how the likelihood of collision increases as both the spatial and the temporal proximities to the tail of an...

Assessing the Role of AVL in Demand Responsive Transportation Systems

Gillen, David
Raffaillac, Julie
2002

Many-to-many demand responsive transportation systems consist of vehicles which take passengers from their origins to their destinations within a service area. In dial-a-vehicle systems, in order to circumvent the undesirable feature of taxicab systems, vehicles are allowed to deviate from their direct route to serve other passengers and the emphasis is on building efficient tours to increase vehicle productivity. This strategy increases riding times but also increases average occupancy and productivity of the vehicles, and hence decreases average waiting times. A similar problem is faced...

Optimal Design of Transit Networks Fed by Shared Bikes

Wu, Liyu
Gu, Weihua
Fan, Wenbo
Cassidy, Michael J.
2020

Transit systems are designed in which access and egress can occur via a shared-bike service. Patrons may walk to shared-bike docking stations nearest their origins, and then cycle to their nearest transit stations where they deposit the bikes. The travel pattern is reversed when patrons cycle from their final transit stations on to their destinations. Patrons choose between this option and that of solely walking to or from transit stations. Shared bikes are priced to achieve the system-optimal assignment of the two feeder options. Transit trunk-line networks are laid-out in hybrid fashion...

Traffic Signal Plans to Decongest Street Grids

Sadek, Bassel
Doig Godier, Jean
Cassidy, Michael J.
Daganzo, Carlos F.
2022

Two new synchronization strategies are developed for signalized grids of two-directional streets. Both strategies are found to reduce congestion significantly more than do other approaches. One of the strategies is static and the other adaptive. Both use a common timing pattern for all signals on the grid but use a different offset for each. The static strategy serves the morning rush by providing perfect forward progression on all streets in the directions that point toward a reference intersection, one that is located near the center of gravity of all workplaces. For the evening rush,...

Jitney-Lite: A Flexible-Route Feeder Service for Developing Countries

Sangveraphunsiri, Tawit
Cassidy, Michael J.
Daganzo, Carlos F.
2022

The paper develops a novel strategy for delivering feeder service in support of trunk-line transit. The strategy is well suited to developing countries, where costs of emergent communication technologies often preclude their use. The strategy, termed Jitney-lite, is a form of collective transportation that provides a degree of flexibility. Patrons who board an outbound Jitney-lite vehicle at a transit station are delivered to their doorsteps. On the return trip to the station, the vehicle boards new patrons in the manner of traditional, fixed-route, fixed-stop feeder-bus service. Continuum...

Could Transportation Network Companies help Improve Rail Commuting?

Darling, Wesley
Cassidy, Michael J.
2024

Commuter rail is known to have a “first- and last-mile” problem (i.e., a lack of options for getting commuters to and from a rail station). The first- and last-mile dilemma creates inequalities in access. For example, high-income commuters drive to work (forgoing transit altogether), middle-income commuters drive to a rail station and pay to park, and low-income commuters rely on feeder buses or walking to reach a rail station. Transportation network companies (TNCs), like Uber and Lyft, are a viable option for connecting travelers to rail stations, especially for those who don’t own a car...