Densely sampled Tracking Data (DTD)Some Applications and Challenges
Val NoronhaDigital Geographic Research Corporation
&University of California, Santa Barbara
20051010. GPS/Time Geography #2
Great GPS Mapping Challenge
20051010. GPS/Time Geography #3
$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?