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Are you interested in human stigmergy and how it works?

Our summary today works with the article titled A survey of environments and mechanisms for human-human stigmergy from 2005 by H. Van Dyke Parunak, presented at the Second International Workshop of E4MAS in Utrecht. Since we are investigating the future of cities, I thought it would be interesting to see the schema to analyse stigmergy among humans. This article presents the examples and suggests how the use of stigmergy can be extended.

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Welcome to today’s What is The Future For Cities podcast and its Research episode; my name is Fanni, and today I will introduce a research paper by summarising it. The episode really is just a short summary of the original paper, and, in case it is interesting enough, I would encourage everyone to check out the whole paper. Stay tuned until because I will give you the 3 most important things and some questions which would be interesting to discuss.

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Stigmergy is the coordination of agents in a shared environment. These agents can be anything: bugs, ants, humans or computers. The essence of stigmergy is the coordination of bounded agents embedded in a potentially unbounded environment. The agents both sense the environment which guides their actions and modify it, as a result of their actions. According to Parunak, stigmergy among humans is pervasive because it is hard to find a functioning social institution without such coordination among people. Accepting that stigmergy is everywhere in human interactions, can help to govern the success of this strategy. Agents always interact locally in the environment so they are not overwhelmed regardless of how big their whole system is. Furthermore, these local interactions can yield a coherent system level outcome that provides the required control for the whole system.

Stigmergy was formed in the study of insects. The term comes from the Greek words of stigma, meaning sign, and ergon, meaning action, and captures the notion that an agent’s actions leave signs in the environment, signs that it and other agents sense and that determine their subsequent actions. So one agent’s actions influence the system, which in turn influences the other agents’ actions. Even though it started with bugs, stigmergy is ubiquitous in the human interactions. Stigmergy seems to be the only way for a large distributed population to coordinate in a distributed system.

In stigmergy, the environment is accessible to the agents with appropriate sensors. Each agent is an individual object with a well-defined boundary, while the environment is not one element, like the Cartesian space or a graph structure. When the environment is not monolithic, each agent is localised in that environment, meaning that their sensors and actions are confined to one region of the environment. If the agent is mobile, it can change location in the environment, but at any moment it is at one location. This localisation allows agents to not get overwhelmed and the stigmergic systems to scale without exceeding the load on each agent.

The interactions and dynamics of the individuals agents are usually nonlinear, resulting in a system that is susceptible to formal chaos. However, this structure enables self-organisation because these dynamics allow the system and agents to explore its state efficiently. There are four varieties of stigmergic interaction depending on the given signals and their nature. An interaction can be marker-based, like insects leaving pheromones, or situation-based, like ants creating cemeteries without special markers. The other distinction is whether the signals are qualitative or quantitative. Whatever the details of the interaction, examples from natural systems show that stigmergic systems can generate robust, complex, intelligent behaviour at the system level, even when the individual agents are simple and individually nonintelligent. In these systems, intelligence resides not in a single distinguished agent, nor in each individual agent but in the interactions among the agents and the shared dynamical environment.

Current stigmergic human interaction can be based on digital computers and not. Humans have long coordinated their activities through non-computational environments, like in movement coordination, market systems, elections, document editing, and viral marketing. These examples were based on non-computational interactions, but they could be enhanced with some technology. However, the advent of information technology has extended the applicability of stigmergic mechanisms for human coordination, through sensing, communication and information processing, like intelligent transportation systems, collaboration environments, recommendation algorithms, scheduling and planning.

There are numerous sensors, computers, and non-digital aspects of stigmergy in human interactions to be improved or preserved. To enhance the transparency of this interaction, human interface devices will be critical. The foundations need to be radically different to allow the new body of theory, the nonlinearity of dynamics, and the nature of emergent behaviour. The stigmergic systems require extensive use of simulation for their design and analysis because of their emergent character. The openness of the information – because individuals act on other individuals’ information – poses a challenge to security and privacy.

Our environment is intrinsic to stigmergy. Not just bugs or computational devices collaborate in a stigmergic way, but any functioning social institution needs to. In stigmery, the system becomes intelligent due to the individual agent’s interactions not because of their individual capabilities. Aspects, such as transparency, simulation and attention to security and privacy can enhance current and future collaborations across humans, strengthening human-human stigmergy.

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What was the most interesting part for you? What questions did arise for you? Do you have any follow up question? Let me know on Twitter at WTF4Cities or on the wtf4cities.com website where the transcripts and show notes are available! Additionally, I will highly appreciate if you consider subscribing to the podcast or on the website. I hope this was an interesting paper for you as well, and thanks for tuning in!

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Finally, as the most important things, I would like to highlight 3 aspects:

1. Stigmergy is the notion that an agent’s actions leave signs in the environment, signs that it and other agents sense and that determine their subsequent actions.
2. Stigmergic systems can generate robust, complex, intelligent behaviour at the system level, even when the individual agents are simple and individually nonintelligent because intelligence resides not in a single distinguished agent, nor in each individual agent but in the interactions among the agents and the shared dynamical environment.
3. Human stigmergy has been based on non-digital systems, however, with the advent of information technology, it can be advanced with special attention to the highlighted aspects like transparency and simulation.

Additionally, it would be great to talk about the following questions:

1. How can you describe your city if it is the emergent property of the inhabitants interacting with each other?
2. What do you think about yourself as an acting agent in a stigmergic system?
3. How could you change your behaviour as an acting urban agent in your city to create a better future?

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