Irrational markets
Network models of financial systems are useful for understanding the inter-connectedness of banks and the fragility of the banking system (11 August, p 6). They are, however, less useful when it comes to predicting the timing of crashes.
The models need to recognise that banking behaviour and financial market behaviour are generally affected by human actions, subject to self-interested economic incentives and, perhaps more importantly, psychological flaws and biases.
Research in behavioural and emotional finance is recognising that bankers and investors are subject to periods of extreme exuberance, overconfidence, excitement and excessively risky investment – as witnessed by the subprime banking crisis. These are followed by periods of extreme pessimism, caution, risk aversion and underinvestment, causing a sequence of extreme bubbles and crashes in markets. Understanding the psychology of participants, and when their mood swings may occur, will help to improve the predictive and prescriptive powers of crash-detection models.
From Richard Hind
While this latest forecasting model is all very interesting, is anything going to change while the financial sector is dominated by greedy, unscrupulous men backed by self-serving politicians? Maybe I should model that concept in a spreadsheet to help them understand my concerns.
York, UK
Comfort and eating
Reading Jim Horne’s article concerning the potential link between childhood obesity and lack of sleep (14 July, p 26), I wonder whether anybody has considered the following: if I have had a stressful day, or am ill, or have spent a great deal of time outdoors or in the cold, I tend to sleep for longer. Surely a child in Victorian or Edwardian times would sleep more, due to their comparatively poorer living conditions, diet and health, and the prevalence of other hardships.
Perhaps the true link to be studied is that between quality of life and obesity. Do centrally heated homes, readily available calories, good healthcare and less stressful lives result in obesity?
Choose free will
Neither Benjamin Libet’s experiments nor those of people who now aim to correct him in the debate on free will are – as they may appear – disinterested enquiries (11 August, p 10). They are all neatly designed to support a 20th-century dogma: the belief that thought cannot possibly influence action. That is clearly why the experiments are so carefully shaped to leave absolutely no work for thought to do.
In real life, by contrast, we need to decide not just when to do a fixed action, but what to do: a climber faces an awkward rock; a physicist confronts a new problem; a tennis player chooses a shot.
What distorts current thinking on this issue is the almost superstitious personification of the brain as something separate from the agent – as a powerful extra character in the drama. In fact, what does the deciding is the whole person. The subjective, bodily and cerebral aspects of that person can be thought about separately, but they are not competitors. They are complementary elements of the whole.
From Patrick Gaunt
Interpreters of Libet’s brain-activity experiment assert that the trigger to act must be internal because the subjects are asked to ignore any external information. But as Arthur says in the 2010 film Inception: “Don’t think about elephants. What are you thinking about?”
The work by Aaron Schurger that you report shows parallels between the behaviour of the human brain and a neural network model. The conclusion ought to be: free will may still exist, but it probably takes a form similar to the free will experienced by a sufficiently powerful computer.
Bingley, West Yorkshire, UK
Self-diagnosis harm
We may be on the verge of a new revolution in medicine with self-management of chronic conditions, as alluded to in Nic Fleming’s look at self-trackers (4 August, p 40). For example, Scotland currently spends around £1.5 billion on unplanned emergency care for such conditions. Saving 20 per cent on these admissions would account for up to 3 per cent of our health budget.
There is, however, an even larger problem with diagnosis through screening. Fleming refers to this in passing when considering preventive mastectomies. The problems for politicians are how to stop or refocus excessive and sometimes harmful screening, and how to appropriately support self-monitoring for those with chronic conditions.
From Christopher Bush
Fleming writes that websites such as Patientslikeme and CureTogether can “generate new medical knowledge”. Such online forums are also breeding grounds for pseudoscience, promoted by desperate sufferers of awful diseases looking for anything that might relieve their pain.
This negative, in my view, far outweighs the positive.
Shipley, West Yorkshire, UK
Frog death spawn
In his article on the fungal disease that is killing amphibians (7 July, p 42), Bob Holmes misses one important and rather frightening point about the spread of the fungus Batrachochytrium dendrobatidis (Bd). Among the first and most striking victims were the golden toad of Monteverde, Costa Rica, and the Australian gastric-breeding frogs Rheobatrachus silus and R. vitellinus – living in protected areas far away from pollution and other environmental influences caused by humans.
It seems that the alleged carriers, the clawed toad and bullfrog, cannot be held responsible for delivering the fungus to these remote locations. We must look for an alternative or additional agent that has been in both Costa Rica and the Australian Rheobatrachus sites. The obvious first vector for Bd is frog scientists and their gear.
Bob Holmes writes:
• The spread in Costa Rica , but biologists do now take precautions when visiting uninfected areas.
Whole in their theory
Discussing the physical relevance of Schrödinger’s wave function (28 July, p 28), Matthew Pusey and his colleagues argue that the two atoms in their thought experiment are truly independent of each other. But they also argue that something controls their behaviour. So if something controls them, they are not independent.
No, the answer to the quantum puzzle is monism: there are no independent parts, just a whole.
Sex-test woes
I wrote a paper about female athletes disqualified after the first “sex testing” of competitors in 1966 and am stunned that similar practices have resumed (21 July, p 26).
What is called into question by such tests, largely of female athletes, is not so much their sex as their humanity. It was devastating to women in the 1960s who were suddenly told they were “not women” by virtue of their genetics; it will be no less so now.
It is a shame that the International Association of Athletics Federations and the International Olympic Committee would practise such a barbaric and discriminatory policy. My heart goes out to those who have spent years preparing to compete, only to be thrown out because of their “unenhanced” bodies.
Deities of Olympus
Of all the amazing physical aptitudes shown in the recent Olympics, double-amputee 400-metre runner Oscar Pistorius indeed stands out, not just for a world-class performance, but for doing it without lower legs (11 August, p 26). Of course Olympians are demigods, as Anders Sandberg writes, but from the heights of Pistorius’s achievement, even they look pretty small.
From Antony Wheeler
How can we get some real scientific value from an Olympics governed by rules restricting testosterone levels, surgical improvements and performance-enhancing drugs (11 August, p 4)?
My vision includes an “anything goes” games. Surgery, drugs, whatever – the first across the line wins. Imagine the scientific benefit from finding out which drugs really do give a competitive advantage. Imagine the benefits to disabled people of serious research and testing in sport of possible enhancements to vulnerable knee joints.
Would the athletes expose themselves to possible side effects from unproven drugs? Why not? A few seem pretty keen already, even though the drugs are illegal. Perhaps athletes would compete not for countries, but in the names of drug firms or university research teams. And forget betting – imagine the effects of winning a gold in the 100-metre sprint on the firm’s share price.
Mackay, Queensland, Australia
Mission impassable
I am all in favour of other nations getting into the race for Mars, but I have concerns for the Dutch programme mentioned in your brief look at possible crewed missions (4 August, p 6).
Those involved claim they will “establish the first [human] settlement on Mars in 2023” and “to fund the one-way trip” will make a TV reality show. One way? That should cut costs by much more than half.
Crab in wrong class
In your Instant Expert on fossils you say “crustaceans such as horseshoe crabs” (4 August). But horseshoe crabs are within the Arthropoda, closely related to the arachnids, and definitely not crustacean. My old professor at Manchester defined crustacea as: “Arthropods with two pairs of antennae; nothing more.” Merostomata have no antennae.