American Association of State Highway and Transportation Officials

Special Committee on Research and Innovation

 

FY2023 NCHRP PROBLEM STATEMENT

 

Problem Number:  2023-G-25

 

Problem Title

A Study of Spatio-temporal Traffic Patterns in Metropolitan Atlanta Using Google Maps

 

Background Information And Need For Research

Urbanization and economic growth in the metro Atlanta region have caused heavy traffic congestions on major roads. According to the 2019 Global Traffic Scorecard by INRIX that was published in 2020, Atlanta is one of the top 10 most congested cities in the United States before the pandemic. For intelligent transportation systems and urban/transportation planning, it is necessary to identify temporal and spatial traffic congestion patterns. Temporal traffic patterns may include, but are not limited to, traffic durations and intensities during morning, afternoon, evening, daytime, and nighttime. Spatial traffic patterns will also tell where certain traffic patterns occur. The main drawback of studying temporal and spatial traffic patterns has been the limitation of available data resources, particularly from field sensors. This research proposes using online traffic layers, like Google Traffic, as a major data source. This research is directly related to the Goals 4 and 5 of “Strategic Plan for the Council on Data Management & Analytics”, approved by the AASHTO Strategic Management Committee on September 17, 2019. Particularly, this research will facilitate the development and advancement of tools to support decision making data and analytics needs (Goal 4.3) and support research to advance the development and use of tools and best practices in communicating data, data management and analytics (Goal 5.1)

 

Literature Search Summary

Analyzing traffic patterns in a metropolitan area has been hampered significantly due to the scarcity of field sensor data. At best, we could identify potential congestion corridors using AADT and road design capacity (e.g., Seong, Kassa, and Choi, 2011, doi: 10.1007/978-3-642-19214-2_30). Recently, crowd-sourced datasets and online traffic maps, however, have opened a new horizon for transportation research. They have been applied to various transportation applications such as transportation policy research (Loop et al., 2019, DOI: 10.13140/RG.2.2.28893.05), congestion forecasting (Pramanik et al., 2020, arXiv:2011.02359 [cs.CY]), traffic flow estimation (Baji, 2020, doi: 10.15201/hungeobull.67.1.5), and level of service calculation (Ali and Abid, 2021, doi:10.1088/1757-899X/1076/1/01201). Our literature search of TRID, RIP, and academic journals, however, does not show any previous research about identifying temporal and spatial traffic patterns in a metro city from geographical perspectives. Our research will pioneer the temporal and spatial aspects of traffic events by incorporating GIS (geographic information systems) and big data analysis techniques.

 

Research Objective

The objective of this research project is to identify temporal and spatial traffic patterns in the metro Atlanta area. Traffic patterns will be analyzed at two different geographical scales: one at the macro scale along the major roads in the metro Atlanta and the other at the micro-scale along the interstate highways. Major deliverables of this research are traffic patterns with the information of when, where, and severity. A website will also be developed to visualize traffic patterns interactively and to share them with Georgia DOT, metro Atlanta MPO, and the public.

 

To achieve the objective, we will construct a 3-D spatio-temporal data cube by sampling Google Maps Traffic Layer every 10 minutes via the Google Maps API, and we will identify temporal traffic patterns by clustering the 24-hour traffic trends at sample points on roads. The following diagram (Figure 1) shows eleven temporal traffic patterns that were derived from a one-day pilot dataset, where the x-axis represents time of a day, and the y-axis represents traffic severity. The inset map shows the extent of the metro Atlanta that were used in the pilot study. In the figure the red line, for example, represents a traffic pattern that has a light traffic in the morning and a very heavy traffic in the afternoon from 3:00 pm to 7:30 pm. We will collect traffic data for 20-weeks, at least, to avoid statistical biases. The optimal number of traffic patterns will be identified, and various temporal traffic-vector clustering techniques will be tested.

 

 

 


 

Figure 1. Temporal traffic patterns identified from a one-day sample dataset

 

We will also analyze the difference between weekdays and weekends. Various geospatial data science techniques will be used such as GIS, Python libraries, R packages, server-side programs like Javascript, and spatio-temporal data visualization techniques. Lastly, we will develop an interactive online mapping application using an online mapping platform such as ArcGIS Online. This research requires extensive resources for 24/7 data acquisition, data post-processing, testing multiple models, validating traffic patterns, visualizing outcomes, and writing reports. Multiple student assistants and research associates will be hired for this project.

 

Urgency and Potential Benefits

As the population of the metro Atlanta area has increased dramatically, road traffic has also increased significantly. Identifying traffic locations and patterns is an important step for a reliable transportation planning. It, however, has been impossible to analyze them for such a large area mainly because of the limited number of field sensors. Utilizing online traffic layers can supplement field sensors. This research will benefit transportation planners and urban planners by providing them with traffic pattern types and their locations. The methodologies that are developed in this research may benefit other state DOT’s and MPO’s to analyze their endemic traffic patterns.

 

Implementation Considerations

The research results of this project will be used by GDOT for implementing the Statewide Transportation Plan (SWTP) and State Transportation Improvement Program (STIP). The Atlanta Regional Commission (ARC), the MPO for metro Atlanta, has recently researched various applications of the Google’s floating car data for their long-term metropolitan transportation planning. This research will support ARC’s transportation and commuting research with floating car data by providing new perspectives about traffic patterns. Our research may also benefit from ARC’s floating car data as a validation source. Research findings will be presented at GDOT and ARC and will be submitted to academic journals for publication.

 

Recommended Research Funding and Research Period

We propose three years to perform this research. Year 1 will collect data and analyze traffic patterns on major roads of metro Atlanta, Year 2 will focus on interstate highways in detail including their ramps and exits, and Year 3 will implement an online mapping platform that allows interactive queries of traffic patterns. University of West Georgia, Georgia Institute of Technology, Atlanta Regional Commission, and GDOT will collaborate on this research. The annual budget will be $298,750 that will include PI and co-PI salaries ($30,000), institutional sub-award ($120,000), research associates ($60,000), undergraduate student assistants ($24,000), supplies ($8,000), travel ($8,000), and IDC 37.5% ($48,000). The three-year total is $896,250.

 

Problem Statement Author(s): For each author, provide their name, affiliation, email address and phone.

Dr. Jeong Seong (PI), Dept. of Natural Sci., Univ. of West Georgia, jseong@westga.edu, 678-839-4069

Dr. Ana Stanescu, Dept. of Math & Comp. Sci., Univ. of West Georgia, astanesc@westga.edu, 678-839-6294

Dr. Clio Andris, Georgia Institute of Technology, clio.andris@design.gatech.edu, 404-385-7215

Dr. Gulsah Akar, Georgia Institute of Technology, gulsah.akar@design.gatech.edu, 404-894-2351

Mr. Habte Kassa, GDOT Office of Planning, hkassa@dot.ga.gov, 404-631-1797

Kyung hwa Kim, Atlanta Regional Commission, kkim@atlantaregional.org, 470-378-1562

 

Potential Panel Members: For each panel member, provide their name, affiliation, email address and phone.

Nokil Park, Atlanta Regional Commission, npark@atlantaregional.org, 404-463-3100

Jim Skinner, Atlanta Regional Commission, jskinner@atlantaregional.org, 404-463-3317

 

Person Submitting The Problem Statement: Name, affiliation, email address and phone.

Mr. Habte Kassa, GDOT Office of Planning, hkassa@dot.ga.gov, 404-631-1797