Pedestrian Potential-Collision Standoffs, and Symmetry Breaking

May 28th, 2016

We’ve all experienced this phenomenon: you and someone else are walking towards each other in opposite directions, and you don’t want to collide. Do you shift to the left or to the right? And how should you shift to avoid a standoff? In a new paper on the arXiv, physicists Nickolas Morton and Shaun Hendy of the Department of Physics at University of Auckland have examined this problem through the lens of statistical mechanics. Here is an excerpt from their abstract:

If both make the same choice then passing can be completed with ease, while if they make opposite choices an embarrassing stand- off or collision can occur. Pedestrians who encounter each other frequently can establish “social norms” that bias this decision. In this study we investigate the effect of binary decision-making by pedestrians when passing on the dynamics of pedestrian flows in order to study the emergence of a social norm in crowds with a mixture of individual biases. (…) We construct a phase diagram that shows that a social norm can still emerge provided pedestrians are sufficiently attentive to the choices of others in the crowd. We show that this collective behaviour has the potential to greatly influence the dynamics of pedestrians, including the breaking of symmetry by the formation of lanes.




Dead Duck Day, June 5th, honoring homosexual necrophilia in the mallard

May 28th, 2016

DeadDuckDay-logoSunday, June 5th, 2016 is the 21st edition of Dead Duck Day, arriving precisely one year after last year’s Dead Duck Day. At exactly 17:55 h [Rotterdam time] we will honor the mallard duck that became known to science as the first (documented) ‘victim’ of homosexual necrophilia in that species, and earned its discoverer the 2003 Ig Nobel Biology Prize.

Dead Duck Day also commemorates the billions of other birds that die from colliding with glass buildings, and challenges people to find solutions to this global problem.

Please join the free, short open-air ceremony next to the new wing of the Natural History Museum Rotterdam (the Netherlands), right below the new Dead Duck Memorial Plaque— the very spot where that duck (now museum specimen NMR 9989-00232) met his dramatic end.

Sarah Forbes

Sarah Forbes

This is what will happen:

  • The traditional Ten Seconds of Silence.
  • Review of this year’s necrophilia news: two new clear cases in birds became known to science, and the first case in a Dutch mammal (!) will be revealed.
  • The reading of the special ‘Dead Duck Day Message’. This years message is send in by Sarah Forbes, former curator of the Museum of Sex (MoS) in New York and author of the book ‘Sex in the Museum’.
  • The announcement of the second performance of ‘The Homosexual Necrophiliac Duck Opera’ in London, on sacred grounds, June 24th, 2016.
  • The first-ever Dead Duck Day Fashion Show. The first batch of t-shirts, designed by Mark Prinsen, will be for sale.
  • A six-course duck dinner, after the ceremony.

The traditional six-course (dead) duck dinner at the famous Tai Wu Restaurant is also open to the public (at your own expense).  Reserve you seat by e-mailing to: info [at]


BONUS: More on the history of Dead Duck Day on the official Dead Duck Day website:

BONUS: Here is Kees Moeliker’s TED Talk about the dead duck:

Car Horn Honking Studies (part 1)

May 27th, 2016

Anyone who has driven a vehicle in various different countries might have observed that the national rate of ‘horn honking’ varies considerably – but why? A widely-cited study by Douglas T. Kenrick and Steven W. MacFarlane (published in 1986) investigated whether one simple variable – temperature – might be having an effect.


The team organised that a “female confederate” driving a Datsun 200SX would repeatedly perform a potentially irritating manoeuvre at a set of traffic lights in Pheonix Arizona.

“When the light turned red, she moved her car to the head of the intersection and waited for a subject to pull in behind her. The confederate then waited for the light to turn green and remained stationary throughout the 12-second course of the light.

The confederate was instructed to keep still, with her eyes forward, car in neutral, foot off the brake, and her hands on steering wheel. Once the green light had changed, the confederate made a legal* right turn on the red light.”

An observer recorded how long the cars which were behind her spent honking their horns. 75 such tests were conducted between April and August, when the “Temperature Humidity Discomfort Index” varied from 86º to 116º (Fahrenheit).

“Results indicated a direct linear increase in horn honking with increasing temperature. Stronger results were obtained by examining only those subjects who had their windows rolled down (and presumably did not have air conditioners operating).”

See: ‘Ambient Temperature and Horn Honking : A Field Study of the Heat/Aggression Relationship’ in: Environment and Behavior, March 1986 vol. 18 no. 2 179-191.

* Question [optional]: Under what circumstances is it possible to make “a legal right turn” on a red light?

Coming soon: Horn Honking part 2


The cat-flap as a psychoanalytic metaphor

May 26th, 2016

CatFlapStefano Bolognini, who is president of the International Psychoanalytical Association explores the usefulness of the cat-flap as a psychoanalytic metaphor in his book ‘Secret Passages : The Theory and Technique of Interpsychic Relations’ (2011 – Routledge).

The book is reviewed by Professor Cordelia Schmidt Hellerau in an essay entitled ‘SECRET PASSAGES:SOPHISTICATING THE CAT-FLAP’ (in: Psychoanalytic Quarterly, Volume LXXXI, Issue 2, pages 443–455, April 2012.) Bolognini’s work, explains the professor :

“[…] provide[s] us with the sense of getting to know a seasoned psychoanalyst who loves his work and generously shares with us not only the highlights of successful interpretations, but also the at times stumbling, tentative, or awkwardly searching steps that will help both, analyst and patient, find their way to the cat-flap.”

The ‘cat-flap’ metaphor in this context is illustrated by passages from the book.

“Perhaps, without our knowing, there was a draft, a door left ajar between our mental apparatuses, or a small opening, almost invisible, like in the great wooden doors of Italian houses in medieval times, at the bottom of which was a swinging flap (a ‘cat-flap’) through which the house cat could come and go unheeded, unseen, and without disturbing its owners, intent on other pursuits. [p. 66]

[The cat-flap] . . . is a good symbol for a structural (it is part of the door) and functional (it was specifically designed so that the cat can carry out its function of catching mice inside and outside the house) device that is not only intrapsychic but also interpsychic. The cat-flap is quite distinct from the door, which allows the passage of people, and from incidental cracks, which allow the passage of mice, clandestine, parasitical guest that harm the community / interpsychic-relational apparatus. [p. 67]”

Bonus Assignment [optional]:

Click to continue reading “The cat-flap as a psychoanalytic metaphor”

The M-through-Z of Social Dilemmas (podcast 65)

May 25th, 2016

Social situations sprout all kinds of awkwardness. You can classify some of those awkwardnesses under the letters M through Z, as we do in this week’s Improbable Research podcast.

SUBSCRIBE on, iTunes, or Spotify to get a new episode every week, free.

This week, Marc Abrahams  — with dramatic readings by Robin Abrahams tells about:

The mysterious John Schedler or the shadowy Bruce Petschek perhaps did the sound engineering this week.

The Improbable Research podcast is all about research that makes people LAUGH, then THINK — real research, about anything and everything, from everywhere —research that may be good or bad, important or trivial, valuable or worthless. CBS distributes it, on the CBS web site, and on iTunes and Spotify).