General Exam

Collaborative Versioning in Cities

Urban planning has traditionally been a top-down process controlled by experts who operate behind closed doors, with only sporadic opportunities for the community to comment through public hearings. Over the past decade, many online platforms have emerged that promise to boost civic involvement by streamlining communication between citizens and government officials, but it is unclear that they actually facilitate meaningful engagement and collective decision-making. Sidewalk Lab’s Quayside Development in Toronto proposed innovative systems for the city, but the project was canceled in large part due to difficulty in creatively engaging with the public, and failure to build the level of trust necessary for community acceptance and approval green2019smart. More effective platforms for collective design and community participation are arguably even more important than any technology embedded in such development projects.

Urban design is a complex and iterative process. Too often, important information is lost as the project evolves, both by designers and in the public presentation of the results. The community sees a coarse snapshot at discrete points in the process, and how one got there is lost. Contrast this with community programming. Github, for example, provides a set of tools by which the programming community and users can see and contribute to the evolution of a design. This can help inform a new model for pubic design processes. “Open Source” is the analog for “participation” – all benefit and all contribute.We believe that this tool for collaboration allows (1) consensus building using accumulated history, (2) exchange of mutual knowledge through remixing, and (3) a transparent process with low barriers to participation.

My research is aimed at developing this model as a real tool for urban design. In my prior work, I have shown how simple version control concepts a la Github can be applied to create families of related designs sakai2015implementation where the evolution can be traced, validated, and discussed. Now we can start to use automated consensus mechanisms and machine-based versioning to elevate the planning methodology to include the public in a constructive way.

The basis for this research is mastery of three areas: [1] public consensus and participation in planning and design, [2] technical support for machine- mediated consensus and discussion, and [3] how we learn, build, and incorporate innovation, using techniques that align with version controlling such as remixing and curating. In subsequent doctoral studies, I will build on this premise and consider ways to enable collaborative versioning with citizens about their city.


Researchers in the City Science Group have been thinking about collective consensus building in cities mainly through a project called CityScope. Within this system, I have been developing and maintaining CityIO, a software layer that acts as an intermediary between simulations, physical tables, and the front end visualization.

An extension of this system could allow citizens to edit their design proposals. This method and the tool supporting it is a kind of collaborative editing that involves citizen participation.

I will pursue methods to organize these examples while addressing concerns about the existing democratic process.

Ultimately, I contend that tools that help the city adopt and revise a master plan over time better reflects the needs of an agile, changing world. With sufficient community input, these plans will also come to better support the values of the residents as the community grows together.


  • Who is saying urban planning process are slow? Why?
  • What is the right size of a community?
  • Does the current method have enough deliberation?
  • What are the recent examples of community engagement in cites?
  • What worked? How are we evaluating?

alexander1962use green2019smart alexander1964city sadik2017streetfight curry2019good tomasello2009we forrester1970urban panagiotopoulos2012online janssen2018innovating rubin2019politics kiewiet1991logic pollitt2004agencies roberts2015age roberts2004public ferrate2010google samuel2020representation

Reader: Kent Larson


There are two perspectives from which I will explore the technical aspects of this idea. The first perspective lies in the scope of Distributed Consensus. There are a variety of consensus mechanisms that are being used in a variety of circumstances from auctions (which agree on value) to automated means that support a currency. These are formalizations of voting systems that are especially germane given that machine-based mediation can channel the noise of low-friction participation in potentially useful ways. The second perspective is knowledge of the technologies that support collaboration in the software industry, which is one of the most successful industry for collaboration currently taking place. These emerged as a combination of version control for software development and community participation in the evolution of a system.


aragon2017deliberative ongaro2014search sakai2015implementation howard2020paxos lynch1989hundred cao2016json Coglan2019 schimpf2010fossil chacon2014pro lamport2019part lamport2019byzantine ali2016blockstack archer2018keys bunz2018bulletproofs kissner2009general merkle1987digital laurie2014certificate blum1983coin blum2020e2e

Reader: Andrew Lippman


The act of creating something new by quoting and combining what others have done is not only essential to scientific pursuits, but is also found in a variety of cultural and creative activities. There are two reasons to explore this.

The first is to look for concepts that underpin collaboration in the other media mentioned above, and explore how they might apply to collaborative work in city and town planning.

The second reason is to confirm how these creative activities, which are premised on others’ intervention, can be established as a community and, by extension, a regional identity, and how this can affect each other in planning and thinking about the neighborhood.


  • Define “collaboration”, effort has been put to define cooperation. How do other words or techniques share this characteristics. e.g “remix”, “curation”
  • How can we categorise different ways to “remix”?
    • syncronized? async?
    • vertical? horizontal?
  • How do current planning methods use collaboration among stakeholders?
  • There is another similar word “bricolage” from Levi Strauss, what other aspects that this word enrich?

hardt2015google lvi1966savage malone2018superminds manovich2005remixing manovich2007comes o2007curatorial lessig2008remix de2011course churchman1967guest bateson1979mind tidball2013positive arnstein1969ladder irvin2004citizen sennett2012together

Area Reader: Gesa Ziemer

Gesa Ziemer (Prof. Dr. phil.) is Professor for Cultural Theory and Cultural Praxis and Vice President Research at the HafenCity University Hamburg. She is currently a fellow of the Humboldt Foundation (Feodor-Lynen Program) at the Harvard Kennedy School, Cambridge, MA, USA. Her research foci are: the digital city, new forms of cooperation, urban public life, and artistic research. She holds a Guest Lectureship at the Lucerne School of Art and Design in Switzerland. She is a member of the Accreditation Committee of the Scientific Council of Germany. Moreover, she is a member of the Supervisory Committee of Hamburg Innovation, a community for the transfer of knowledge in Hamburg, and a member of the Advisory Boards of Lucerne School of Art and Design and the Choreography Centre PACT Zollverein Essen. She regularly serves as an evaluator, i.a. for the Deutsche Forschungsgemeinschaft, the Swiss National Science Fund, German federal ministries, and private foundations (e.g. Volkswagen, Robert Bosch).

General Exam: Feedback General Exam: MAS format


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