Navigating an urban environment beyond the shortest path

The first thing that comes to someone’s mind when the term Smart City is thrown around, is efficiency! Efficiency in energy consumption, efficiency in city government operations, efficiency in transportation and so on. Efficiency in transportation has become synonymous to fast/short transportation. But is this really making us, the city-dwellers, smart(er)? Isn’t this making us prisoners of time? Is this what we really want from our cities of the future? Efficiency? For sure efficiency in some (many) aspects is top priority (e.g., energy), but when it comes to navigating through the urban fabric efficiency should not be our top priority. Cities are living organisms and people are the nutrients that they need to survive and thrive. Consequently, following always the same efficient paths will lead to inadequate nutrition of specific parts of the city. Not to mention that this minimizes serendipity (and potentially your chance of finding love as Ariel Sabar describes in “Heart of the City: Nine Stories of Love and Serendipity on the Streets of New York“)

Daniele Quercia and his colleagues developed alternatives to shortest path routing, by considering routes that make people feel happy, routes that are filled with delightful smells (e.g., the smell of a bakery early in the morning) and routes that allow you to experience the city through its sounds. This was a breakthrough in urban way finding and inspired us to take it a step further. Why focus on a single objective for navigation? After all if we focus on a single objective most probably we are still minimizing serendipity, since the path that makes us the happiest will always do so! How about if we really have to be at school by 5pm but at the same time we want to increase our exposure to trees, or to street art? This is an example of multi-objective routing, where we want to find paths that optimize two (or potentially even more) objectives. There are several challenges associated with the problem of multi-objective routing with the two most important being:

  1. Many times the two objectives are conflicting, for the simple fact that a longer path will have more of everything (trees, street art, etc.).
  2. There are many many paths connecting two points in a city and each one of these provides different tradeoffs between the two objectives. However, we cannot show all these paths (possibly tenths or even hundreds) of paths to a dweller.

Luckily we have developed an algorithmic approach that is able identify a small set of paths that capture the different trade-offs that are possible given the structure of the road network. While one can see the technical paper for details, the main idea is to identify what we call non-dominated or Pareto optimal paths. These are paths for which there are no other paths that are better with respect to all the objectives of interest! To visualize that we can assume that every path is characterized by two values, x and y, that represent the performance of the path with regards to the two objectives. Let us assume that we are interested in maximizing the x-objective and minimizing the y-objective. If we plot the values for every pair of possible paths between our original and destination we will get a plot like the following:

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We are interested in paths that lay on the red line (called Pareto frontier or skyline, depending on the field literature you are reading). In this artificial example, there are only few paths on the frontier, but in a real network, there can be tenths or hundreds of paths. We have developed an algorithm for choosing a small number of them (7-10) that covers all the major tradeoffs. For example, the two points in the orange circle practically offer similar tradeoffs between the two objectives and hence, we can return to the user one of them.

Application

We have used our algorithm to provide paths in the city of Pittsburgh that offer tradeoff between length and exposure to trees! For the latter, we used a nice dataset recently released that includes information for the trees cared for and managed by the city’s  Department of Public Works Forestry Division.  Hence, our objective is to minimize the length of the path, while maximizing the exposure to trees, making for a relaxing path. For example, let us assume that we want to go from Oakland to Shadyside. There are many paths to follow and the following map shows 4 of them (the ones returned by our algorithm).  The user can choose between the shortest path (the blue one), which is also the one with the smallest exposure to green, or the greenest path (the…green path), which is also the longest path! We also offer the user the choice of two other paths (red and black) that are neither the shortest nor the greenest, but they are non-dominated (i.e., would provide a good tradeoff)!

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One can think of several other objectives that can be included such as safety of biking/driving (e.g., due to a snowstorm), exposure to historic landmarks, exposure to places with personal significance to the user etc. The possibilities are only limited by the  data available to us!

This research is part of the PittSmartLiving project, which aims to put humans into the center of urban navigation and cyber-physical systems in general, and facilitate the design if systems that are truly smart – both technically but also socially!

Five things we have learned about incentives

Will people wait 30 minutes for the next bus, if they can get $2 off from the sandwich shop across the street? What if it’s raining? What if the Penguins have just lost a game? Researchers in the PittSmartLiving project are trying to understand how external and internal factors (such as weather and emotions) affect how we trade off time and money. These questions not only help us understand more about human behaviors, but also are the key to develop solution to transform Pittsburgh into a smart and sustainable city. This is the idea behind our NSF-funded project that seeks to simultaneously fuel up marketplace and multimodal mobility with a smart mobile app and data analytics.

Our initial survey, conducted in February 2017 through the University Center for Social and Urban Research (UCSUR) with close to 900 Pittsburghers, reveals some interesting things about incentives:

  1. Reliable information means more than money:

65% of our respondents said they would use public transit if they had better information on bus capacity and arrival times. Surprisingly, only 57% said the same when asked about monetary incentives.

  1. ..especially for the older population:

Most of our respondents over 60 would not change their travel behavior given monetary incentives, however, would do so when given more reliable information.

  1. Higher income = harder to change:

Regardless of the incentive offered, Income is negatively associated with the willingness to use public transit. Though we have not solved the money = happiness dilemma, it seems that more money does buy less bus tickets.

  1. More education = easier to change:

Controlling for income, age and having a car, we find that the effectiveness of incentives increases with education.

  1. Not all incentivizes are created equal: cash is the best:

64% of our respondents ranked cash incentives the highest. This preference for cash is unchanged across all income and education groups.

What’s next?

This is just a start! In the following months, we will start a series of studies focusing on how people make day to day decisions with regards to time and money. We will examine these questions through survey, controlled experiments in the lab, and novel field experiments. Stay tuned! (Feel free to follow us on twitter and/or contact us)

 

Postdoc Position in Economics and Computer Science

The Graduate School of Public and International Affairs at the University of Pittsburgh has an opening for a 2-year post-doc position in Mechanism Design for Social Applications, with a possible extension to the third year. This position supports collaboration between GSPIA and the School of Computing and Information (SCI).

 The collaboration includes Pitt Smart Living, a project funded by a $1.4M National Science Foundation grant: ‘Building a Smart City Economy and Information Ecosystem to Motivate Prosocial Transportation Behavior’ (#1739413). The post-holder will play a significant role in building a marketplace around public transport, including designing time-sensitive coupons from local businesses to rebalance transit riders at rush hour.  Working with Profs Sera Linardi (experimental economics), Alexandros Labrinidis (data science), Yu-Ru Lin (computational social science), Adam Lee (data privacy) and with Prof Onur Kesten in an advisory role (Carnegie Mellon University, market design), the post holder will use theoretical modelling and lab and field experiments to:

  • investigate commuters’ response to uncertainty in travel time
  • model firms’ decision problem in offering coupons,
  • match commuters to coupons

The project aims to not only publish in academic journals but also create and deploy practical applications. Other projects may include mechanism design for social work.

Candidates should have a strong background in market design.  A background in transport economics is helpful but not necessary.  The candidate should be near completion of a PhD in microeconomics, computer science or similar fields. Review of applications will begin February 18, 2018, and will continue until the position is filled. Applications should include a curriculum vitae, copies of written work, and a motivation letter addressing candidate’s broader interest in social applications of mechanism design. Two letters of reference should be sent directly by the referees. Applications and request for further information can be sent by e-mail to: Prof. Sera Linardi (linardi@pitt.edu)

Western PA Mobility Showcase

We are excited to be a part of the Western PA Mobility Showcase that the Department of Mobility and Infrastructure (DOMI) of the City of Pittsburgh is organizing.

The Showcase will be open to the public, free of charge, on Thursday, January 4, 2018, from 12 noon to 2pm and 5pm to 7pm at Alumni Hall at the University of Pittsburgh’s Alumni Hall (4227 Fifth Ave).

Be sure to stop by our booth, learn more about the project, and participate in our survey (to win an iPad)!

More information about the showcase at http://bit.ly/WPAmobility

Light Rail arrivals now showing in Pittsburgh City Hall

We are happy to report that the PittSmartLiving display at the lobby of the historic City-County Building now includes real-time information about light rail arrivals for the nearby Steel Plaza station. Many thanks to the Port Authority for making that data available and to TransitScreen for incorporating the data feed.

As always, the transportation data feed can be accessed at http://tsgo.io/pghcityhall (even from your mobile phone).

t-station-screenshot
Screenshot showing arrivals for the Blue line (Nov 27, 2017)

Additional information:

New PittSmartLiving display at Carnegie Library of Pittsburgh – Main

TransitScreen Display in the Lobby of the Carnegie Library of Pittsburgh – Main

We are very happy to announce that one more PittSmartLiving display went live recently, in the lobby of Carnegie Library of Pittsburgh – Main (in Oakland). The display provides location-specific real-time information about:

  • Port Authority bus arrivals
  • HealthyRide bicycle availability
  • Pitt Shuttle arrivals
  • Current Weather

This makes the Carnegie Library of Pittsburgh the 4th Public Library in the USA that has a TransitScreen installation. The screen can also be accessed online, at https://tsgo.io/carnegielibrarypgh (even from your mobile phone).

This is the seventh display of the PittSmartLiving pilot project which aims to evaluate the benefits of making multimodal transportation information available in real-time to city-dwellers, through public displays and a mobile app (forthcoming).

If you have any feedback for this or any of the other PittSmartLiving displays, please contact us.

Multidisciplinary Team Receives National Science Foundation Funding to Improve Transit [Pittwire]

A multidisciplinary team of Pitt investigators has received a three-year, $1.44 million NSF grant to build and evaluate a marketplace and a mobile app for multimodal transportation. The marketplace will provide incentives such as discounts at nearby businesses to encourage riders to take a later bus if the next one is full.

The funding will enable the Pitt Smart Living Project to place additional multimodal, realtime transportation information screens around the city. A half-dozen screens are located in Oakland and Downtown in collaboration with TransitScreen, through seed funding from the University.

Read more: Pittwire Accolades article

PittSmartLiving project gets $1.44 million from the National Science Foundation

We are excited to announce that our team has received a three-year, $1.44 million NSF grant to design, develop, deploy, and evaluate a marketplace and a mobile app for multimodal mobility, as part of our PittSmartLiving project. The marketplace will, for example, provide personalized incentives for people to take a later bus if the next one is full. The mobile app will enable multimodal trip planning, where for example part of the trip is done by bus and part of the trip is done by taking a HealthyRide bicycle or a Pitt Shuttle.

The funding will also allow us to place an additional 10-15 multimodal real-time transportation information screens in Pittsburgh. These will supplement the half-dozen locations in Oakland and Downtown already deployed in collaboration with TransitScreen, a DC-based company providing displays of real-time information. The pilot project was paid for through seed funding from the University of Pittsburgh.

Principal investigators are project leader Alexandros Labrinidis, project co-leader Konstantinos Pelechrinis, Adam J. Lee, and Yu-Ru Lin of the School of Computing and Information; Sera Linardi of the Graduate School of Public and International Affairs; and Kent Harries and Mark Magalotti of the Swanson School of Engineering.

In addition to TransitScreen, we are excited to collaborate with the Port Authority of Allegheny County, Healthy Ride, the City of Pittsburgh, Oakland Business Improvement District,  the Pittsburgh Downtown Partnership, Envision Downtown, the Oakland Transportation Management Association, Pittsburgh 2030 District, Radius Networks, UPMC, the University of Pittsburgh Department of Parking, Transportation & Services, the University of Pittsburgh Office of Community and Governmental Relations, the University of Pittsburgh Center for Social & Urban Research, and Daniele Quercia, Head of the Social Dynamics team at Bell Labs, Cambridge UK.

More information about the project can be found at https://PittSmartLiving.org. For news and updates, you can also follow us on twitter (@PittSmartLiving) and Facebook (@PittSmartLiving), or you can check out one of the project’s screens in Oakland and Downtown Pittsburgh.

Pitt Smart Living project hopes to ‘democratize,’ incentivize transportation [The Pitt News]

A Pitt research project is attempting to “democratize” and incentivize public transportation in Pittsburgh using public information screens and a mobile app.

The Pitt Smart Living project is currently in the pilot phase, according to Alexandros Labrinidis, the Pitt computer science professor leading the project. This phase involves installing screens, powered by startup company TransitScreen, displaying data from multiple feeds — including Port Authority buses, Pitt and UPMC shuttles and Healthy Ride bikes.

Read more: The Pitt News article by John Hamilton

TransitScreen provides real-time transportation information at City-County Building [Post-Gazette]

TransitScreen, the service to inform commuters about the availability of all kinds of transportation options that began in Oakland in April, is now available at the City-County Building, Downtown.

The free service is essentially a display monitor that tracks Port Authority buses, ride-share services like Lyft and Uber, car-sharing service Zipcar and Pittsburgh’s bike-sharing program. The service usually is provided by a large employer, but the local system is paid for as a demonstration project by the University of Pittsburgh as part of its Smart Living project to see if the monitors can be used to encourage commuters to spend their time waiting for transportation at shops and restaurants.

Read more: Post-Gazette article by Ed Blazina