Densely sampled Tracking Data (DTD)Some Applications and Challenges

Val NoronhaDigital Geographic Research Corporation

&University of California, Santa Barbara

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Great GPS Mapping Challenge

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$2,000 D-GPS vs $150 PDA-GPS

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Retail Forecasting

Where will Joe buy shoes?• “Nearest” store• Utility-maximizing choices: attraction/

distance … gravity/Huff model• Distance from where?

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Distance

• Straight line• Network-routed• GPS-calibrated• Perceived 7:30

7:43 8:22

8:41

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DTD in Retail

Beyond the ATM/transaction record• Field of Habitual Experience: sort of a

Time-Space Prism w/ a spatial awareness component?

• Frequency of visitation (big-ticket)• Chaining the shopping trip• Impulsive choices: where, how often?

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Microscopic DTD

• Data– Segment times, congestion– Intersection delays and queueing– Intra-segment behaviors

• Applications– Road hazards– Familiarity, decision making

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Technical Challenges

• Accuracy: getting worse?• Power and the lukewarm start

:• Data integration: continuity of (Λ,Τ)

– Remote sensing– Loop detectors

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Privacy Issues

• Coarsening data: residual use?– Variety of applications very broad

• Spoofing data … de-spoofing data• If we accept cookies, prepare to get

tracked

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Thank you!

Questions?