Following on from our previous article covering ‘The Wasted Chewing Gum Bacteriome’, we will be steering away from Ecological-based science and moving towards an entirely different field.
The key word being ‘moving’…
That’s right – you guessed it. This week, we will be looking at Kinetics.
More importantly, Ig-Nobel Prize Winning Kinetics.
A Quick Reminder – What are the Ig-Nobel Prizes?
If you have read any of our previous articles on the subject of the Ig-Nobel Prizes – you can skip this section! If, however, you have never heard of this award ceremony then keep reading for a quick introduction.
The Ig Nobel Prizes were set up to honour those people and projects that make people laugh, then think. The prizes are handed out for the weird, the imaginative, the unusual – anything that can spur people’s interest in science, medicine or technology.
Usually, the ceremony is held every September as a gala-type event in Harvard University’s Sanders Theatre. Unfortunately, in a Covid blighted world this was not possible so the entire event was streamed online.
It is possible to watch the full event for free by clicking here.
Previous ceremonies have had the prizes presented to recipients by Nobel Laureates in front of the massed 1100 spectators. Thousands more watch along online.
The Kinetics Prize
The 2021 Kinetics Prize was handed to a team of researchers from Japan, Switzerland, and Italy. The team consisted of Hisashi Murakami, Claudio Feliciani, Yuta Nishiyama, and Katsuhiro Nishinari – who conducted research into why pedestrians do sometimes collide with one another.
The prize was handed over by Carl Weiman (a previous winner of the Nobel Prize in Physics). In the acceptance speech for the award there is a great simplified explanation of what the research uncovered, as well as a brilliant visual demonstration of the findings in action.
If you would like to see the award and acceptance speech from the team behind ‘Mutual Anticipation can Contribute to Self-Organisation in Human Crowds’, then the timestamp to navigate to is 57:17.
The background to ‘Mutual Anticipation can Contribute to Self-Organisation in Human Crowds’
According to the introduction of the research paper (with reference to other papers), crowds of humans are known to take part in a wide variety of self-organising behaviours, in a similar vein as to how birds flock or fish school. Research has already been undertaken into understanding human crowd behaviour and the pedestrian flows within them to improve management of mass events and pedestrian transportation. Some collective patterns of human organisation in crowds have even been shown to contribute to horrible events like trampling.
Conversely, there other phenomena that provide functional benefits to the group as a whole – even if there is no ‘conductor’ or external control. Lane formation has been observed, where unidirectional lanes are formed spontaneously in bidirectional pedestrian flows. This unconscious organisational pattern lowers the risk of collisions between pedestrians and enhances the flow of traffic. As such, it is clear to see the applications of research into this area with crowd management.
We were fortunate enough to receive a response from Claudio Feliciani, one of the award-winning scientists involved in this project. Claudio had already covered some similar work as a PhD student, completing experiments investigating the bidirectional flow of pedestrians. The promising results from this were enough to encourage Hisashi Murakami (the first author of the project) to get involved, who added another layer by observing the cognitive component in the collective motion of people.
This was well received by Claudio, who was full of praise for his colleague and said this extra layer was important in –
“… making the image complete.”
Claudio’s compliments towards the rest of team help to underline a possible factor of their success – their team dynamic. As a team they bounced well off one another, Murakami’s incredibly diverse theoretical knowledge and experience complimented brilliantly by Claudio’s technical knowledge and know-how from similar experiments with people.
“…even if you have a good idea, it is usually difficult to put it into practice alone or it may not work as expected because the idea might be good, but details always play an important part.”
A Snapshot of ‘Mutual Anticipation can Contribute to Self-Organisation in Human Crowds’
For the purpose of this article the findings of the research paper have been simplified, with some parts omitted. If you would like to read the full, original paper – you can do so for free here: https://www.science.org/doi/10.1126/sciadv.abe7758
Influence of visual distraction on the emergence of lane formation:
Experiments involving two groups of 27 pedestrians along a ‘mock corridor’ in a bidirectional flow were undertaken. An additional task was imposed on three of the participants in one of the two groups to visually distract them and potentially disrupting their anticipatory reactions with others. The distraction for this experiment was the use of a mobile phone while walking.
The hypothesis for this experiment was that distracted pedestrians at the front of the group (facing directly into the oncoming crowd) would have the biggest influence on crowd dynamics. In order to put this hypothesis to the test, three experimental conditions were set – front, middle, and rear (in addition to the control with no distraction).
For the front condition in the experiment, three participants were selected at random to walk at the frontmost positions of their group while distracted by a phone. The other conditions were very similar to this, but distracted participants were assigned to either the middle or rear. For each condition, the experiment was repeated 12 times.
Figure 1 – Bidirectional Flow Experiments with Distracted Pedestrians.
- Snapshot of experiment under the front condition (where the distracted pedestrian is at the front of a group).
- Representative examples of reconstructed pedestrian trajectories, where yellow indicates movement of left to right, and red indicates movement of right to left. (Murakami, Feliciani, Nishiyama and Nishinari, 2021)
Photo credit: Hisashi Murakami, Kyoto Institute of Technology; The University of Tokyo
The development of traffic organisation over time is shown in Figure 1 B). The pedestrians would walk towards one another in opposite directions and in order to avoid colliding would deviate from the most direct path. The pedestrians were found to self-organise themselves into two or more unidirectional lanes and then follow straight courses, with the front condition distracted pedestrians disturbing this behaviour the most.
How to reach such an interesting hypothesis?
Arriving at this hypothesis was by no means a straightforward process.
Previous experiments with people walking in two opposite directions along a corridor piqued the researchers’ curiosity – who had noticed that the way in which people moved before making lanes was markedly different to the movement once organized into lanes. The team also noticed that people had a tendency to move laterally when there was the same number of people moving in each direction – which they concluded is likely due to no single group being dominant and able to communicate their intentions, leading to a sort of ‘mutual agreement’.
Claudio states –
“… we had some clues that some form of communication occurred and which kind of information is exchanged was not clear. Communication form is still unclear, but we know it is a mutual process in which people indicate their future positions and, at the same time, read the one of the people from the opposite direction.”
Act natural, we’re being watched…
Working with humans as subjects of experimentation sometimes presents ethical or moral challenges. Neither of which were an issue with this research project.
In fact, the challenges the researchers had to overcome and the considerations made for this particular project were much more humorous in nature –
“Getting participants behaving in a natural but yet “neutral” way is always a challenge. If people bring emotion during the experiments results may change and it is difficult to assess whether the surprising results was due to a particular situation or is indeed a new discovery.”
One of the earlier experiments undertaken by the researchers encountered this problem.
The participants (pedestrians) were told that the following run was going to be the last. Because of this, the motivation (at the thought of a break) and speed of the participants increased – leading to the final run also being the fastest. Usually, the walking speed of participants would remain largely stable during the day or decrease slightly as they began to get tired.
This anecdote reiterates the point that experiments must always be well organised and without a clear structure so the participants cannot predict what comes next. If this happens, they may try to prepare for an anticipated situation and their behaviour may change.
Claudio reminds us –
“…finding a combination between a schedule which seems random to the participants but whose instructions are easy to understand is always a challenge.”
Response from the scientific community
There has been a sense of surprise surrounding this research due to the many novel components. Although similar experiments have been performed by other researchers in the field, relatively few have had the imagination to use coloured caps and a birds-eye view to observe lane formation.
There has also been a lot of attention given to the distraction element of the project – with this in particular being a hot topic of discussion.
“…attention has been given on the fact people were walking with the smartphone, although that was only a way to distract people and we also considered having them read a book. The smartphone solution was simply chosen as it would be more natural for participants…”
Although it is now understood that people will mutually communicate with one another while walking through a crowd, and that their future position is conveyed – it is still unclear how exactly how this is communicated.
Claudio gives us a glimpse of the future –
“…we are working with eye-tracking glasses to understand what are people looking when they take a specific action. I hope to get more involved with people from psychology/cognitive science as there is a lot to learn from them.”
This study goes a long way to explaining something we have all experienced, but have likely never given much thought to. Next time you’re walking down a busy street and think about using your phone, spare a thought for the people behind you…
As you can imagine, setting up a research project like this takes a lot of effort. Claudio describes the project as –
“Fun but a lot of work!”
Just because something is difficult and doesn’t work first time does not mean an idea is doomed. Even award-winning researchers encounter their fair share of roadblocks – but as Claudio reminds us, a positive mentality when a problem is encountered is the key to a successful project.
“Try to always understand what the true fundamental mechanism you want to study… always think twice on what you really want to know, and whether that is the real cause behind the problem. Of course, failing is always good, but one should also understand what was the failure to learn.”
A special thank you…
To Claudio Feliciani for selflessly giving up his time to answer our questions about the project he was involved in. For each question posed to him, Claudio provided in-depth and insightful answers – which makes writing articles like this an awful lot easier!
Without his responses, this article would not have been possible. So, we would like to take this time to give our thanks and wish Claudio and the other researchers the very best of luck with any future research projects.