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Stanford Research Park Commute Map• Steve Raney, Pitman Avenue, Cities21.org, U.C.
Berkeley Transportation Planning• Transportation Research Board Jan. ’03 paper• Thanks
– Joe Kott, Amanda Jones, Dave Matson - GIS Mgr– Chris Augenstein – VTA, Mike Skowroneck, MTC– Prof. Robert Cervero & John Landis, Berkeley
• Funding– Cities21– Palo Alto staff time + map printing
Why?• “Because of the upcoming Highway 101 Corridor
Study, planned Caltrain Baby Bullet service, Stanford General Use Permit trip reductions, and ongoing VTA/SamTrans bus route planning, Palo Alto needed more accurate and more current commute data than other cities and transit agencies. Compared to recent regional transportation studies, our data is twenty times more precise and our participation rates are much higher.” – Joe Kott, City of Palo Alto Chief Transportation Officer.
Why? - Transit Route Planning
• VTA ’99 Major Emp. Center Zip Code Study – 5 new routes (1,000 riders), modified 50% of
commute routes, new park & ride lots, marketing for specific routes
• How many people within X feet of a bus stop?
• NJIT mathematical bus optimization algorithm• TALC: “There is no existing means to effectively match new
bus service with worker’s travel patterns. Transit agencies are forced to predict where commuters need to go, instead of being able to use actual data.”
Privacy-Protecting Data CollectionEmployer creates employee address spreadsheet (15 minutes processing max):
Under employer supervision,addresses are aggregated to1/5 mile grid. Multiple employers.Privacy is protected:
1/5 mile grid: 4 blocks or 144 houses.
Methodology• U.C. Berkeley grad student study
– Endorsed by PA Transportation Dept.– Privacy validated by PA GIS
• 161 companies, 20 largest, 20K emps• Mid-peninsula Commute Forum kickoff• PA Trans letter (“patriotic” appeal)• 25 contacts per company - limited escalation• On-site geocoding• 280 hours (<100 hr improvement exists)
• Worst possible timing
• 13/20 participated => 8,200 addresses
• 7 declines (details withheld):
Methodology - (2)
Company E.U. Privacy Genl. Privacy Time Database1 20% 80%2 100%3 100%4 100%5 80% 20%6 33% 66%7 80% 20%
Proactive Ridesharing Marketing• Oil shock scenario
• Improve marketing targeting
• Questions?
Employees Employer PA/VTA
EmployerEmployees PA/VTA
Addresses 1/5 Mile Grid
Request Zip code
Identify promising
neighborhoods
National Implementation
• Edge cities - 181 > Memphis in last 25 yrs– Decentralization of jobs => congestion
• Zero last 2 address digits, secure web collection
• Eliminate cost of individual commute shed studies– Prepare a national legal opinion on aggregation
• Run nationally every 3 years
Palo Alto PRT Feeder Forecast• Commute Shed• Education
– Model, 3D VR
• Qualitative interviews– Basket of solutions
• Stated preference.
Data Protection / Privacy
• Cautious environment
• "We have to assume that some day this data will get out. Employees will go 'nonlinear' if we give out this data. We are very, very sensitive to this possibility. If we can err on the side of privacy, we do, even if it appears externally to be 'stupid.'”
E.U. Privacy Directive 95/46/EC
• Commerce Dept. Safe Harbor Agreement
• Adopted as unstated corporate privacy policies
• Requires employee consent to provide addresses
• Test: personally identifiable.
E.U. Directive: Anonymization• "in which data may be rendered anonymous and
retained in a form in which identification of the data subject is no longer possible … using all means that are reasonably at their disposal."
• No “aggregation precedent”, Brussels: no help• 4 U.S. privacy experts• Corp. attorneys: unfamiliar, not geography experts• “Eyes on data” - on site geocoding• Voluntary participation.
