Would you trust these eyes?

January 30, 2013

A recent blog post at Science 2.0 reported on a fascinating study by a team of researchers from Charles University in Prague. These researchers published in PLOS One their findings on the relationship between eye colour and perceived trustworthiness of faces.

Which of these two people looks most trustworthy?

Photos by Randen Pederson (L) and “Garrett” (R) – click for details

The team (Karel Kleisner, Lenka Priplatova, Peter Frost, and Jaroslav Flegr) showed photographs of 40 male and 40 female faces to their subjects, and asked them to rate how trustworthy the faces looked. They found a significant relationship – brown-eyed faces were perceived as more trustworthy.

Kleisner, Priplatova, Frost, and Flegr found (after controlling for “dominance” and ”attractiveness”), a very significant (p < 0.001) link between eye colour and perceived trustworthiness, in both male and female faces (image from their paper)

The genius of Kleisner et al., however, was not to leave it at that, but to repeat the experiment after altering the eye colours on the photographs. This revealed that eye colour per se had no effect. Rather, the perceived trustworthiness was linked to aspects of facial shape – aspects that normally correlate with eye colour.

They write: “brown-eyed faces tended to have a rounder and broader chin, a broader mouth with upward-pointing corners, relatively bigger eyes, and eyebrows closer to each other. This was also the pattern of a trustworthy face.

These results are consistent with earlier work by Alexander Todorov, Sean Baron, and Nikolaas Oosterhof, who found that not only are certain facial shapes perceived as trustworthy, but that these faces generate a measurable response in the Amygdala, detectable with functional Magnetic Resonance Imaging. I’m not sure why this brain response exists, but presumably it is one of the things which confidence tricksters exploit.

Would you trust this brown-eyed man? Frank Abagnale, whose life was portrayed in the film Catch Me If You Can (photo by “Marcus JB”)

– Tony

School Shootings – Can Potential Shooter Profiles be Identified?

January 8, 2013

In light of the recent shootings, in Newtown, Connecticut. New debates have been sparked on the idea of gun control and identification of potentially unstable individuals who could commit such crimes.

An article on Science Daily website, School Shootings: What We Know and What We Can Do, highlighted some recent research studying past events and tragedies to accumulate a profile of potential shooters and how these individuals can be identified ahead of time. The article uses research by Dr. Daniel J. Flannery on explaining how shooters demonstrate similar features such as depression, low self-esteem, narcissism and a fascination with death. However these key aspects and similarities across shootings are not strong enough to produce conclusive profiles which could allow for future prevention of such tragedies.

Other research has produced similar findings, Leary, Kowalski, Smith and Philips (2003) analysed multiple shootings between 1995 to 2001. They found that depression, low self-esteem and narcissism were all present in the individuals involved in the shootings. However they all also shared one more common attribute and that was social rejection. Social rejection alone cannot fully explain these acts of violence as most people navigate through life and at some stage are exposed to social rejection. However this social rejection coupled with psychological problems or a fascination with death may lead to acts of violence occurring.

Unfortunately research in this area is inconclusive and therefore specific attributes and characteristics have not been idenitifed to put in place preventative measures to reduce the chances of such tragedies occuring again.

– Stefano

Human Sciences, Statistics, and R

January 6, 2013

The use of statistics has long been important in the human sciences. An early example is an analysis by William Sealy Gosset (alias “Student”) of biometric data obtained by Scotland Yard around 1900. The heights of 3,000 male criminals fit a bell curve almost perfectly:

Histogram © A. H. Dekker, produced using R software

Standard statistical methods allow the identification of correlations, which mark possible causal links:

XKCD teaches us that “Correlation doesn’t imply causation, but it does waggle its eyebrows suggestively and gesture furtively while mouthing ‘look over there.’”

Newer, more sophisticated statistical methods allow the exploration of time series and spatial data. For example, this project looks at the spatial distribution of West Nile virus (WNV) – which disease clusters are significant, and which are merely tragic coincidence:

Distribution of significant clusters of human WNV in the Chicago region, from Ruiz et al.

SPSS has been the mainstay of statistical analysis in the human sciences, but many newer techniques are better supported in the free R toolkit. For example, this paper discusses detecting significant clusters of diseases using R. The New York Times has commented on R’s growing popularity, and James Holland Jones points out that R is used by the majority of academic statisticians (and hence includes the newest developments in statistics), R has good help resources, and R makes really cool graphics.

A really cool graph in R, using the ggplot2 R package (from Jeromy Anglim’s Psychology and Statistics Blog)

An increasing quantity of human-science-related instructional material is available in R, including:

Through the igraph, sna, and other packages (and the statnet suite), R also provides easy-to-use facilities for social network analysis, a topic dear to my heart. For example, the following code defines the valued centrality measure proposed in this paper:

valued.centrality <- function (g) {
  recip <- function (x) if (x == 0) 0 else 1/x
  f <- function (r) sum(sapply(r, recip)) / (length(r) - 1)
  apply (shortest.paths(g), MARGIN=1, f)

This definition has the advantage of allowing disconnected network components, so that we can use these centrality scores to add colour to a standard plot (using the igraph package within R):

Social network diagram, produced using R software, coloured using centrality scores

– Tony

Emergence, Intelligence, Networks, Agents: WEIN

December 1, 2012

Networks are ubiquitous, and often large. The WWW contains over a trillion pages. The Internet contains over 900 million hosts. Facebook has over 900 million active users. The human brain contains over 80 billion neurons. The world has over over 7 billion people.

The behaviour of such networks is determined not just by the behaviour of individual nodes, but also by the network topology. The famous six degrees of separation often hold, for example. Network dynamics and self-organization are also important.

From the nodes and links of these large networks, fascinating things emerge. Nobody expected what happened when a small internal network at CERN was scaled up to planetary size, for example. And somehow, the interactions of our billions of neurons make us intelligent.

The 5th International Workshop on Emergent Intelligence on Networked Agents (WEIN’13) will be exploring some of these phenomena at AAMAS in Saint Paul, Minnesota next May.

The WEIN 2013 Call for Papers is out, and submissions are due January 30. It is likely to be an interesting event, and one that should help to build bridges between the multi-agent system and complex network communities.

Bridging disciplines: the PLoS One Map of Science

– Tony

Driver Distraction – are we being distracted away from real solutions?

October 29, 2012
Person using cell phone while driving.

Person using cell phone while driving. (Photo credit: Wikipedia)


Driver distraction is a major cause of accidents on our roads.  More research into driver distraction is therefore welcome.


Traditional media available in vehicles, such as radios and entertainment systems, can affect visual attention, and the current use of GPS navigation assistance and personal communication devices have been repeatedly shown to interfere with the primary driving vigilance and motor control task.  Such research has informed road authorities to restrict their use, particularly with regard to mobile phone use and texting for example.


The introduction of Intelligent Transport Systems has the potential to overload the driver if such systems are not tailored to driver workload according to location, traffic density and other ambient conditions.  A more accurate and layered approach to driver workload and attention level can provide a structure upon which information can be conveyed appropriately and distractions reduced or minimised.

Hume Freeway looking south towards Victoria, r...

Hume Freeway looking south towards Victoria, running parallel to Albury railway station. (Photo credit: Wikipedia)


There are many instances however where use of communication devices in vehicles may actually help in vigilance (for example, long distance driving) and the ability to operate a mobile office whilst driving has undoubted productivity benefits.  The problem is that the driving environment can potentially change in milliseconds and cause an overload of the driver’s available perceptual and attentional resources.


The aspect of appropriate speed limits in long distance driving could also be re-addressed.  There has been a spate of single driver transport accidents on the Hume Freeway recently which have had tragic (and potentially disastrous consequences). Apart from driver fatigue and scheduling issues, is the posted speed limit too low to maintain sufficient driver arousal levels?  Long boring drives at inappropriately low speeds could also encourage further distraction (such as use of mobile devices) perhaps even increasing the potential danger.  This may not be ideal given that the severity of an incident at 100kph is still as catastrophic as one at 110 or 120kph.  If speed kills, then surely it follows that the only safe speed is zero. There is a balance between the efficient movement of goods and the consequences of error.  Does this mean that interstate transport needs to travel at 40kph so that any incidents that occur are relatively minor? Would this result in more incidents because drivers would be bored out of their minds whilst blowing out transport schedules? There needs to be an open discussion by professionals in the field as to assessment of all of the risks rather than the current thinking that slowing traffic is the only solution as seems to be the case at present.  The posted speed relative to the road design and condition could be reducing driver arousal and performance level below the desired optimal range.


60KM/H Speed limit sign in Australia.

60KM/H Speed limit sign in Australia. (Photo credit: Wikipedia)

The Human Machine Interface (HMI) remains central to safe and effective vehicle operation as the information it provides will allow the driver to retain effective control of the vehicle and help influence or even determine their behaviour. Information flow to the driver must be intuitive, readily understood, timely, and be responsive to driver attentional and distraction state.  Unfortunately, there are many who have very little understanding of this requirement. For example, presentation of the “bells and whistles” mentioned in this proposed level crossing warning system  may actually distract a driver at the worst possible time and cause more problems than the technology is trying to solve. Human scientists understand the many facets that determine the best way of presenting information so that it is perceived, recognised and acted upon in an optimal manner.  If the proponent of this system had engaged human factors expertise in the first place or heeded their advice he may not have made such ill-considered comments. Perhaps he may get some guidance as to the importance of listening to human factors professionals when he presents his data at the upcoming ITS conference in Vienna. It would be good to have some critical assessment by any human scientists attending this conference of any actual (rather than derived or contrived) interactions that occurred during the trials which were conducted of this system.


The area of human interaction with technology is very complex and simplistic approaches (such as further unrestrained visual or auditory “bells and whistles blaring”) will rarely be the best solution.  All the more reason to design and test proposals from a human science standpoint, heed the results and incorporate them into any proposed system.  Which underscores the importance of the many respected facilities that incorporate human science input as a keystone of their research in ITS applications, vehicle design and driver behaviour.  Hopefully their research findings are weighted appropriately (ie. seen as valid and reliable) by the governing authorities as compared to those of the “bell and whistle” variety.










Sleeping in the moonlight… or not

August 21, 2012

Moritz von Schwind, Selene
and Endymion‎, 1831

In 1609, the English writer Thomas Dekker wrote these lines in praise of sleep:

For do but consider what an excellent thing sleep is: it is so inestimable a jewel, that, if a tyrant would give his crown for an hour’s slumber, it cannot be bought … sleep is that golden chain that ties health and our bodies together. Who complains of want, of wounds, of cares, of great men’s oppressions, of captivity, whilst he sleepeth? Beggars in their beds take as much pleasure as kings. Can we therefore surfeit on this delicate ambrosia? Can we drink too much of that, whereof to taste too little tumbles us into a churchyard; and to use it but indifferently throws us into Bedlam? No, no. Look upon Endymion, the Moon’s minion, who slept threescore and fifteen years, and was not a hair the worse for it. Can lying abed till noon then, being not the threescore and fifteen thousandth part of his nap, be hurtful?

Full moon (from Weird
Tales, Sept 1941)

The modern prevalence of jet travel and shift work has prompted considerable research in sleep and sleep-related issues, since many travellers and shift-workers struggle to find effective strategies for managing sleep. Thomas Dekker is certainly correct about the effects which sleep deprivation can have.

However, although Selene (the Moon) caused Endymion to sleep, she is unlikely to be of any help here. In fact, the full moon reduces hours slept, and this effect may underlie traditional beliefs in lunacy caused by the moon. Not to mention the legends about werewolves.

– Tony