# Collective Deliberation with Physicalizations

Nathalie Bressa, Samuel Huron

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Nathalie Bressa, Samuel Huron. Collective Deliberation with Physicalizations. ACM Conference on Designing Interactive Systems 2024, Jul 2024, Copenhagen, Denmark. Physicalization from Theory to Practice: Exploring Contemporary Challenges for Physicalization Design https://data-physicalization.github.io/fromt2p-dis2024/. hal-05165232

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# Collective Deliberation with Physicalizations

Nathalie Bressa

nathalie.bressa@telecom-paris.fr

i3 (UMR 9217), CNRS, Télécom Paris, Institut
Polytechnique de Paris

France

Samuel Huron

samuel.huron@telecom.paris.fr

i3 (UMR 9217), CNRS, Télécom Paris, Institut
Polytechnique de Paris

France

<figure><img src="image_2.png" /><figcaption>Figure 1: Voting with pebbles Greece, 490 BC, attributed to the Brygos Painter. Getty Museum, 86.AE.286</figcaption></figure>

## ABSTRACT

Data physicalization is a promising approach to support co-located collaborative deliberation processes by visualizing information relevant to the deliberation. In this position paper, we first explain the potential of physicalizations for collective deliberation. Then, we identify a set of considerations for designing new physicalization systems for deliberation.

## KEYWORDS

Physicalization, deliberation, input visualization, participatory data physicalization.

## 1 INTRODUCTION

The first representation of a democratic deliberation process is depicted on a Greek wine cup from 490 B.C (Figure 1). In ancient Greece, dropping a pebble in an urn allowed citizens to express their opinions on political matters. Counting the stones provided the mechanism which anchored one of our earliest voting systems. Transferring the scenario to our times, this is an example of a physical representation of data used in deliberation. The collected data are the opinions of voters, and the representations are the pebbles. A dedicated deliberation process may accompany or precede the vote itself.

Although dedicated deliberation processes have been shown to reinvigorate democratic practices [11] in the face of waning trust

in democratic institutions [10], there remains a lack of tools specifically tailored for in-situ deliberation. Deliberation is an exchange of arguments leading to choice [9] and as such, a crucial mechanism for decision-making, particularly on divisive issues such as climate change. Despite the importance of deliberation, few works have focused on creating tools specifically to support deliberation in situ. Increasing numbers of digital civic technology platforms [13] aim to facilitate remote asynchronous civic participation but face poor participation rates and accessibility challenges [4], particularly for non-digitally literate participants.

In information visualization, the support of decision-making through visual representations of data has a been investigated extensively. While physicalizations have a historic tradition in the use of deliberation, they have only recently emerged as a dedicated research direction in the information visualization field. Work in information visualization on decision-making has mainly focused on single-user desktop computer tools that support displaying a large number of data dimensions to help weigh options with the help of charts. What is primarily missing are tools for the participation of multiple people in a larger deliberation process. Physicalizations are a promising approach to address this challenge because physical tools support people with different backgrounds and digital novices due to their tangible nature, potential for collaborative and co-located use, and ability to collect complex data with simple actions [3, 6, 12].
## 2 CONSIDERATIONS

Physicalizations have the potential to support co-located collaborative deliberation processes by visualizing relevant information, providing a shared view of changing opinions and arguments of people, and enabling people to physically change and manipulate this shared overview. For example, physicalizations could be used to collect, record, and represent multiple arguments, opinions, and positions of people over time during a deliberation process. Designing physicalizations for deliberation remains an open research challenge. We need to better understand what should be represented during deliberation, how it should be represented, and how to design people's interaction with the physicalizations. The following are potential considerations for designing physicalizations for deliberation processes:

(1) **Expected outcome.** There are various collective deliberation scenarios [1] that can lead to different outcomes. For instance, resolving problems within a community group has a different expected outcome than establishing policies, participatory budgets, or planning of new facilities. Resolving a community problem likely results in reaching a consensus or compromise among people. Establishing policies usually leads to defined rules described in a text. A participatory budget results in quantitative data, while planning new facilities results in a description of temporal data and required actions. As a result, the process of collective decision-making can yield diverse outcomes in terms of data formats and types. Specifying the intended expected outcome is crucial for the deliberation process and the design of an appropriate physical representation.

(2) **Data.** What should be represented is an important question for collective deliberation with data physicalizations. We distinguish three potential types of data: data on the topic being deliberated or discussed, data that represents aspects of the deliberation or discussion, and data that represent the outcome of the deliberation or discussion.

**Data on the topic.** Data physicalization can support deliberation by collecting data from participants that are related to the topic of the discussion, as in Edo [12] or Let's play with data [5, 7].

**Data on the deliberation.** The physicalization can also represent aspects that directly relate to participants' deliberation activities. For instance, voting on a question, as seen in Figure 1, or arguments and stances in consider.it [8].

**Data on the outcome.** Another type of data can correspond to the expected outcome. For example, in a participatory budget deliberation, a physicalization of the future budget can be used to support the discussion. However, this representation does not reflect the deliberation process itself.

(3) **Representation.** Designing the visual representation of a collective physicalization that is assembled by potentially multiple participants synchronously over time comes with unique challenges related to input visualizations [3]. This includes aspects such as designing a dynamic visual mapping, constraints on the mapping, the assembly model and input modalities, and the different states of the physicalization over time.

(4) **Process.** Physicalizations can support different aspects of the deliberation process. They could be used before to inform the discussion, during to externalize the thoughts and positions of the participants, and after as a tool to summarize, comment on, and analyze the resulting process. Similarly, the timing of interacting with, constructing, or inputting data into the physicalization might occur at different stages of the deliberation. It is important to consider how to appropriately design the procedure to take into account social interaction biases such as conformity, leadership influence, self-censorship, and others [2].

## 3 CONCLUSION

In this position paper, we acknowledge the history and potential of using participatory physical representation of data to support collective deliberation. We highlight considerations for future research and design. In particular, we list different types of data that can support the deliberation: data on the topic, the deliberation process, and the outcome. We see a great potential in re-exploring the millennia-old tradition of using physical representations to support future participatory collective data driven decision-making and sense-making.

## ACKNOWLEDGMENTS

This project was supported by the Living Lab 5G project financed by the Banque Publique d'Investissement (BPI).

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