Cell Phone Traffic Data Technology Demonstration in Minnesota ITS America 2007 Annual Meeting & Exposition Bernie Arseneau, Mn/DOT Rashmi Brewer, Mn/DOT Dr. Henry Liu, University of Minnesota Adam Danczyk, University of Minnesota June 2007

Advantage of Cell Phone Probe- based Tracking Cell Phone Tracking Cell Phone Tracking –Over 215 Million Cell Phones Nationwide –Infrastructure already present –Offer point-to-point travel times/speeds compared with the loop detector’s “Estimation” –Does not require installation of new detectors

How the Cell Phone System Works Road Segments and Cell Boundaries

AirSage Coverage

Project Partners Mn/DOT Mn/DOT –Funding –Evaluation support AirSage, Inc. AirSage, Inc. –Provides cell phone traffic data system –Contractual agreement with Sprint, providing the cell phone network University of Minnesota, Center For Transportation Studies University of Minnesota, Center For Transportation Studies –Evaluation and data collection –Overall evaluation report Hennepin County Hennepin County –Business Plan

Evaluation Approach Freeway Section (I-394) Freeway Section (I-394) –Compare with loop detector travel time data High Speed Signalized Roadway (T.H. 55) High Speed Signalized Roadway (T.H. 55) –Compare with floating car data Urban Signalized Roadway (CSAH 81) Urban Signalized Roadway (CSAH 81) –Compare with manual license plate matching data **

Freeway Section (I-394) Description Loop Detectors Loop Detectors –½ mile spacing 30-Second Data 30-Second Data Existing Mn/DOT Travel Time System Existing Mn/DOT Travel Time System

High Speed Signalized Roadway (T.H. 55) Description Full Actuated Coordinated Traffic Signal System Full Actuated Coordinated Traffic Signal System Floating Car Will Assess Travel Times Floating Car Will Assess Travel Times **

Urban Signalized Roadway (CSAH 81) Description Semi-Actuated Coordinated Traffic Signal System Semi-Actuated Coordinated Traffic Signal System License Plate Sampling License Plate Sampling Use Digital Voice Recorders to collect last 4 license plate digits Use Digital Voice Recorders to collect last 4 license plate digitsPlateLetterNumber1Number2Number3Upstream Entry Time Downstream TravelTimeF5424:05:204:08:583:38

Data Collection AirSage, Inc. AirSage, Inc. Mn/DOT Mn/DOT U of M U of M

Data Sample for Freeway Section (I-394) AM Peak

Data Sample for Freeway Section (I-394) PM Peak

Data Sample for High Speed Signalized Roadway (T.H. 55)

Data Sample for Urban Signalized Roadway (CSAH 81) AM Peak

Data Sample for Urban Signalized Roadway (CSAH 81) PM Peak

Statistical Analysis Aggregated Scale Aggregated Scale –Paired T-Test Evaluation Based on Time of Day (AM Peak, Mid-day, PM Peak, Evening, Weekend Day, Weekend Evening, etc.) Based on Time of Day (AM Peak, Mid-day, PM Peak, Evening, Weekend Day, Weekend Evening, etc.) Disaggregated Scale Disaggregated Scale –Percentage of time that AirSage’s value falls within 90% confidence interval –Exception for T.H. 55, as it does not have a continuous data source Hypothesis Testing Hypothesis Testing

Next Steps Continued Data Collection Continued Data Collection Statistical Analysis Statistical Analysis Final Report – Fall 2007 Final Report – Fall 2007

Future/Opportunities It’s success depends on statistical confidence when compared with ground truth conditions It’s success depends on statistical confidence when compared with ground truth conditions If results are positive, then cell phone tracking will likely offer a promising future for travel time estimation If results are positive, then cell phone tracking will likely offer a promising future for travel time estimation

Thank you! Questions?