Friday, January 27, 2012

Mapping the Growth of Manhattan

My colleague Vishaan Chakrabarti proposes to fill in New York Harbor in order to connect Manhattan to Governor's Island. Here is a NY Times story about his idea. While I don't really think this should be a priority for the city, it does have precedent and is interesting to think about. The above image shows the growth of the southern tip of Manhattan, and you can see that a substantial portion of the area is built on landfill. Considering the value of land in this area building more of it makes sense. Or made sense then, anyway. Now that employment in the area is shrinking and residential population is growing I don't think the economics of creating new land can justify new landfill. Consider that firms outbid households for real estate because they will either benefit from increased productivity, access to markets or can pass their costs on to consumers. Households seek to maximize their amenity value and reduce transport costs. In the case of lower Manhattan, financial firms--the richest firms in the world--are not outbidding households for these lands. So the commercial value is declining to the point that residential uses are more profitable. That doesn't suggest we need more land.

In any event, here is a link to a map of the Bridge's Survey of Manhattan from 1807. The grid is laid out (I believe this is the Commission that created the grid introduced in 1811 but am not positive) and the original features of the island are noticeable. You can also pan and zoom on the map, which is pretty cool.

Wednesday, January 25, 2012

Visualizing NYC Taxi Activity


New York City Taxi Activity from Juan Francisco Saldarriaga on Vimeo.


Above is an animation of yellow cab origins and destinations in New York City by time of day. This is drawn from some current research of mine where I am exploring the ways that taxi services complement conventional fixed route transit. In the video there are a couple of things to notice. First, and I argue most important from a planning perspective, is that taxi origins and destinations are geographically asymmetrical. This matters because it means that individual's travel journeys are multi-modal. If we want to have transit oriented cities we have to plan for high quality, door-to-door services that allow spontaneous one-way travel. Yet for all of the billions of dollars we have spent of fixed-route transit and the built environment we haven't spent any time thinking about how taxis (and related services) can help us reach our goals.

The second thing to look for changes by time of day. In the AM rush lots of Upper East Side travelers head to Midtown. (Origins and red and destinations are blue). By midday Midtown is largely in balance with origins and destinations. In the evening, there are many Manhattan to Queens and Brooklyn trips.

Here is the abstract of my current paper (with Jon Peters and Matt Daus):


ABSTRACT

            Taxi services are critical aspects of urban transportation systems. Taxicabs serve the public in a variety of ways, from metered fares to informal jitneys, and provide critical mobility for people of all income levels. Despite the ubiquity of taxi service in cities, there is limited scholarly research that explores how people use taxi service to support transit-oriented lifestyles and enhance mobility, and there is scant research exploring the complementary aspects of taxi service for conventional transit.  In this paper we argue that taxi service is a critical aspect of a transit system, and taxi usage exhibits complementary characteristics to conventional transit. Specifically, taxi usage is asymmetrical where origins and destinations have very different spatial distributions. This suggests that taxi riders have multi-modal travel journeys. In many cases taxi trips are part of journeys that began with transit trips, yet planning and expanding taxi service as an extension of transit networks is rarely undertaken in practice.  We use regulatory and Global Positioning System (GPS) data from  New York City as a case to demonstrate the asymmetrical nature of taxi usage and innovative regulatory approaches that foster high rates of taxi usage that complement transit ridership.

Wednesday, January 11, 2012

Columbia Urban Planning at TRB 2012

The annual Transportation Research Board's conference is coming up and Columbia's Urban Planning Program is well represented. I'll re-post closer to the conference with better formatting, but here are the projects that some of our best PhD students will be presenting. My sessions are listed below theirs.

Xiaohong Pan will present in session 574 (1/24/2012 1:30-3:15):
Senior Population's Transportation Preferences to Access Health Care Services: Insights from 2009 National Household Travel Survey (12-3251)
     
Population aging is now progressing rapidly in the U.S., which brings significant social and economic challenges to each and every stakeholder in the society. As seniors age, their health care needs surge and they more likely need alternative means of transportation. Considering the increasing burden of population aging that lays on the U.S. health care system, it is important to improve seniors’ transportation access to health care services. However, before planners and policy makers can provide any appropriate and effective assistance, it is crucial to first understand seniors’ transportation preferences to access health care services. Utilizing the most recent National Household Travel Survey (2009 NHTS) data, this paper examines how different socio-demographic, spatial, and transportation attributes affect seniors’ transportation choices to access health care services. The study results indicate that, many seniors are still driving, and they prefer auto travel than public transportation; increasing density alone might not be a powerful and effective strategy to change seniors’ travel mode choices, at least not for the current generation; mode choice of health care trips are inelastic to some transportation attributes, such as travel distance. In addition, the results suggest that,although improving traditional public transportation is important, helping seniors, especially those live in suburban and rural area, to travel using their preferred means is essential as well.


Lauren Fischer will present in session 789 (1/25/2012 4:30-6:00):
Competition from the Curb: Survey of Passengers on Discount Curbside Bus Operators in Eastern and Midwestern U.S. Cities  (12-3838)
    
This study summarizes the results of a survey of passengers using discount “curbside” bus operators to foster a greater understanding of the composition and preferences of the travelers these carriers serve. The study compares the characteristics of passengers on the two largest operators, BoltBus and Megabus, with those using conventional bus lines such as Greyhound. Surveys were administered in the three most heavily served curbside-bus markets in the East and Midwest—six cities in total— resulting in a cumulative sample of 1,025 responses. Curbside bus service is shown to generate a considerable amount of new travel, with newly generated trips accounting for 22.0% of all passengers. In the East, however, curbside bus service is taking a particularly large number of travelers from passenger trains. More than a third of those surveyed (34.0%) report that they would have ridden trains had curbside buses not been available. Ridership is comprised heavily of passengers in the 18-25 age group and overwhelmingly comprised of passengers traveling for pleasure or personal matters rather than for business. Interpreted broadly, the findings support the notion that the curbside-bus phenomenon is not primarily the result of a shift in market share from conventional bus lines. The evidence instead suggests that curbside service should be regarded as a new mode that attracts the vast majority of its passengers from commercial flights, trains, and private automobiles, and that is has grown dramatically in spite of the relative lack of business travelers. 

Authors
     Schwieterman, Joseph P., DePaul University
     Fischer, Lauren A., DePaul University 



I will be in the following four sessions:

Event Number:135
Event Title:Taxi Research: Priorities, Practices, and Opportunities
Event Date:Jan 22 2012 9:00AM- 12:00PM
Event Location:Hilton, Columbia Hall 2
Event Description:The workshop is one of the first activities of the joint taxi subcommittee and will be significant in creating a conversation regarding the role of the taxicab as a part of the transport community. The discussion includes key issues in integrating taxis into general transportation as well as the roles the taxi plays in paratransit. The workshop will attract a wide range of transport professionals, those active in taxi research and those wishing to expand and explore the role of taxis.
Event Agenda:
Title of talk:
Taxi Technologies: Potential for Innovation in Scheduling, Delivery, and Assurance (P12-6770)
    
Event Number:175
Event Title:Best Practices in Parking Management and Pricing: Lessons Learned from Recently Implemented U.S. Programs
Event Date:Jan 22 2012 1:30PM- 4:30PM
Event Location:Hilton, Columbia Hall 6
Presiding Officers:Weinberger, Rachel R. - University of Pennsylvania 
Sponsored By:Transportation Demand Management (ABE50)
Emerging and Innovative Public Transport and Technologies (AP020)
Congestion Pricing (ABE25)
Parking Management (ABE50(1)) 

Event Description:Pricing on-street and off-street parking to achieve an occupancy target and providing users with real-time information on parking availability and price would eliminate the issue of drivers circling for underpriced parking. This workshop brings together academics and city parking managers implementing advanced parking policies and systems. Technologies that monitor and transmit parking availability information, advanced metering systems, and data-supported pricing approaches will be covered.

The idea has been advanced that 30% of urban traffic is comprised of people who have arrived at their destinations and are looking, or cruising, for parking. Recent advances in how we think about cruising and in the technology that has been developed to deal with it have allowed cities to implement new strategies to reduce this excess auto use. In this workshop we will discuss cruising and the available tools to address it. We will present four cases highlighting the ways that cities of different size and character have begun to address cruising. We will learn from each other's experiences.
Overview: (40 minutes)
- Cruising for Parking: Public Consequences of Private Choices
David King (Extent and nature of cruising, how cruising and it's impacts on a neighborhood are measured)
- Technology Toolbox for Parking Management and Enforcement
Daniel Mitchell, (Modern meter technology and its use in parking management and enforcement)
Case Studies (80 minutes)
- Jay Primus, San Francisco
- Damon Harvey, Washington, D.C.
- Mary Catherine Snyder, Seattle
- Jessicas ter Schure, Santa Monica
The Future is Here (20 minutes)
- Balaji Prabhakar
Break-out discussions moderated by the panelists (25 minutes)
Re-convening and sharing results of break-out (15 minutes)

Presentations:
  Cruising for Parking: Public Consequences of Private Choices (P12-6255) 
     King, David - Columbia University
  Technology Toolbox for Parking Management and Enforcement (P12-6256) 
     Sedadi, Amir H. - City of Los Angeles Department of Transportation
  Case Study: SFPark (P12-6258) 
     Primus, Jay - San Francisco Municipal Transportation Agency
  Case Study: Washington, DC (P12-6259) 
     Harvey, Damon - District of Columbia Department of Transportation
  Case Study: Seattle (P12-6260) 
     Snyder, Mary Catherine - City of Seattle Department of Transportation
  Case Study: Samta Monica (P12-6261) 
     ter Schure, Jessica - Nelson\Nygaard Consulting Associates
  Frontiers in Parking Management (P12-6262) 
     Prabhakar, Balaji - Stanford University





Event Number:297
Event Title:Congestion Pricing, Parking Pricing, and Managed Lanes
Event Date:Jan 23 2012 10:45AM- 12:30PM
Event Location:Hilton, International Center
Event Description:
Event Agenda:

Slow Down, You Move Too Fast: Use of Tolls by Taxicabs in New York City (12-2101)
    
The for hire automobile market (taxis, limousines, vans and car share programs) represent an interesting group of automobile users. From the perspective of travel demand, ownership of an automobile is a key determinant in vehicle usage. As such, users who pay per use may have very different demand patterns than conventional users. In addition, the use of road pricing to manage automobile demand is of considerable interest both to manage congestion and greenhouse gasses as well as to raise revenue. This paper explores an area that has not yet received much study, which is the impact of toll prices on route choice and travel demand in for hire car usage. Utilizing a unique data set of medallion taxi cabs in New York City, the authors are examine impact of road pricing on route choice and travel time for taxi trips between lower Manhattan and LaGuardia airport in Queens. Taxicabs on these trips have the option of using the Queens Midtown Tunnel, which is tolled, or the Queensboro (formerly 59th Street) Bridge, which is free.We find in general that paying a road toll does decrease the travel time to the airport, but that the time reduction does not yield a benefit greater than the toll cost. Taxi passengers should heed the opening lyric of “The 59th Street Bridge Song” and “slow down, you move too fast.” Unless users have extremely high values of time, toll road use in taxis represents a cost greater than the benefit. However, we find that taxi drivers are made better off by taking the tolled tunnel through higher tips and shorter trip times.

Authors
     King, David , Columbia University
     Peters, Jonathan Richard, City University of New York, Staten Island



Event Number:477
Event Title:Rethinking Paratransit
Event Date:Jan 24 2012 8:00AM- 9:45AM
Event Location:Hilton, Georgetown West
Event Description:
Event Agenda:

Taxicabs for Improved Urban Mobility: Are We Missing an Opportunity? (12-2097)
    
Taxi services critical pieces of urban transportation systems. Taxicabs come in a variety of ways, from metered fares to informal jitneys, and provide critical mobility for people of all incomes. Despite the ubiquity of taxi service in cities, there is limited scholarly research that explores how people use taxi service to support transit-oriented lifestyles and enhance mobility, and there is scant research exploring the complementary aspects of taxi service for conventional transit. In this paper we argue that taxi service is a critical aspect of a transit system, and taxi usage exhibits complementary characteristics to conventional transit. Specifically, taxi usage is asymmetrical where origins and destinations have very different spatial distributions. This suggests that taxi riders have multi-modal travel journeys. In many cases taxi trips are part of journeys that began with transit trips, yet planning and expanding taxi service as an extension of transit networks is rarely undertaken in practice. We use regulatory and Geographic Positioning System (GPS) data from New York City as a case to demonstrate the asymmetrical nature of taxi usage and innovative regulatory approaches that foster high rates of taxi usage that complements transit ridership.

Authors
     King, David , Columbia University
     Peters, Jonathan Richard, City University of New York, Staten Island
     Daus, Matthew , City University of New York, Staten Island