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Truths and Myths about Traffic Data Truths and Myths about Traffic Data ITSA Presentation June 2007 AirSage Proprietary & Confidential.

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Presentation on theme: "Truths and Myths about Traffic Data Truths and Myths about Traffic Data ITSA Presentation June 2007 AirSage Proprietary & Confidential."— Presentation transcript:

1 Truths and Myths about Traffic Data Truths and Myths about Traffic Data ITSA Presentation June 2007 AirSage Proprietary & Confidential

2 A discussion about terminology and perspectives on traffic data  #1: What is “Probe Data”?  #2: Sensors verses “Probes” … Is that the right comparison?  #3: What does Coverage mean?  #4: Can Congestion be predicted?  #5: Is carrier data free/cheap? … Easy to get? … Easy to work with?  #6: What do GPS equipped vehicles do for traffic monitoring?  #7: How do you define accuracy?  #8: Do multiple data sources increase data quality?

3 AirSage turns anonymous cellular signals into real-time, comprehensive traffic and transportation-related information  Speeds  Travel Times  911 Incident Detection  Historical Data  Congestion Detection  Highways and Arterials Delivery of:

4 # 1: “Probe Data” -----  Wireless Signal Extraction (WiSE)  Probe Data: Specific units (e.g. delivery trucks, busses) reporting back speeds -Floating Car Data -Cell Probe Data -Fleet data (e.g. delivery trucks, 18-wheelers)  GPS Data: GPS units collecting speed data  Wireless Signal Extraction (WiSE) Data: -Anonymous cell phone signal data -GPS data from 50,000,000+ cell phones

5 # 2: Sensors cover a limited number of roadways  After billions of dollars in investment, less than 10,000 miles of roadways are covered by sensors  According to self-reported state data, operate with a 20% down-time -Breakages require work zones and crews to repair  Safety  Deaths -Maintenance and periodic calibration of sensors is expensive

6 # 3: Coverage is measured in many different ways  Coverage is measured using different methodologies -Lane Miles -Directional Miles -Centerline Miles (industry standard)  Coverage is measured using different data sets -Flow Data -Incident Data -Historical (”Predictive”) Data  Coverage is measured using different market sizes

7 A view of sensor data around Washington DC indicates limited flow coverage… Washington DC Sensor Coverage Map

8 … And a historical and “predictive” coverage map indicates data from as far away as West Virginia… Washington DC Historical Coverage Map

9 … While WiSE technology provides comprehensive coverage of highways and arterials (hundreds of thousands of centerline miles … several orders of magnitude more than current sources)

10 # 4: Congestion can not be predicted…  According to the FHWA and The Texas Transportation Institute: Between 55%-60% of congestion is non-recurring  Accidents can not be predicted  Impact and severity of accidents can not be predicted  Historical data used as a basis for traffic information can not be modeled to “predict” the “unpredictable”

11 #5: Is carrier data free/cheap? …. Easy to get? … Easy to work with?  Wireless carriers are in an intensely competitive industry; they require a substantive return on their investment  Formally supported programs take time but are essential -Long term contract and Service Level Agreements in place -Firewall approvals -Internal department and deployment approvals  Wireless carriers use different equipment (e.g. Nortel, Motorola) -Provides different types of data -Requires unique data processing

12 # 6: GPS equipped vehicles can not detect congestion # 6: GPS equipped vehicles can not detect congestion  There are over 230 million vehicles on the road today; Probe fleets represent less than 0.3% of vehicles on the roads today  Probe fleets are often comprised of commercial vehicles -Prohibited from many roadways during rush hours -Have different driving patterns -Often report back as little as once per hour  General Motors (2005 study): >5% of vehicles, or 11,000,000, would be required to cover the major US roadways  The International University of Monaco (2003 study): 2.4% of all vehicles, or 5.5 million, would provide only a 50% chance of detecting congestion

13 # 7: “Accuracy” - What does it mean?  Segment lengths – 1, 5, 15?  Speed within 5, 10, 15 mph of GTD (Ground Truth Data)  Average Accuracy: -Severe congestion -Moderate congestion -No congestion  Overall Average Error (mph)  Severe Misses (off by one category or 25mph)

14 # 8: Do you need multiple data sources to ensure accuracy & reliability?  In the past, aggregation of traffic data was necessary -15 to 20 different DOT sources -Minimal sensor coverage -No alternative sources of data  Today, Wireless Signal Extraction (WiSE) technologies provide comprehensive coverage -All highways -All major arterials  GPS fleets of 500,000 on top of 50,000,0000 does not increase the value of data  More data sources are necessary only when current data quality is poor and/or fragmented

15 A discussion on terminology and perspectives  #1: Wireless Signal Extraction (WiSE) is a disruptive approach to traffic data collection efforts  #2: Sensors cover a limited number of roadways  #3: Coverage claims can be misleading  #4: Congestion can not be predicted  #5: Expertise and relationships in working with wireless carriers is a fundamental requirement for WiSE traffic data collection  #6: GPS equipped vehicles offer little value today  #7: WiSE data provides reliable and accurate traffic data  #8: Multiple data sources do not necessarily mean better data quality

16 Thank You Thank You ITSA Presentation June 2007 AirSage Proprietary & Confidential


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