Four articles this month and it’s a pretty mixed bag. The most controversial article of the bunch is one that links autism with wealth, but the one drawing a link between human intelligence and disease rates in different countries comes a close second. Then, there’s the highly speculative paper that offers a new model of the universe that abandons the familiar Big Bang. Finally, just for fun, there’s one article talking about a cheap and effective way of deterring thieves from stealing your car.

Autism, disease of the rich?

The precise causes of autism is as yet unclear and it doesn’t help matters that there’s a major anti-intellectual movement that attempts to link the disease to vaccination. This post on Neuroskeptic points out that autism appears to be more common in rich countries than poor ones, which is odd, but might be explained by the fact that many cases of autism in poor countries might simply be undiagnosed. A new paper however attempts to correct for this ascertainment bias and it discovered that not only were incidences of autism more common in richer countries, they were also more common among richer people in rich countries, independent of ethnicity.

The post notes that this is a clear case of correlation but makes no definitive claims about causation. It does offer some ideas about how being rich might make your children more likely to be autistic (richer parents might more often choose to have children later in life) or how being more likely to be autistic also makes you more likely to become rich (because the traits associated with autism might also be associated with interest in complex intellectual problems that might come in useful in certain professions or trades). All this is naturally speculative and prone to revision, but I think it’s a great example of how semi-casual observation can easily lead to counter-intuitive and highly interesting results.

Disease makes you dumber

The second article covers very similar territory except in this case the results are in line with intuition. It has long been known that the average intelligence of the human species, as measured by various IQ tests, appears to be rising for the past several decades. At the same time, the average intelligence in different parts of the world are not equal. Trying to offer any type of explanation to either of these puzzles has been controversial for obvious reasons. This article from The Economist highlights a theory that addresses both of them at the same time.

Researchers at the University of New Mexico propose that the effects of infectious diseases account for both observations. Places with lots of parasites and other types of pathogens harm the brain development of children who grow up there. As sanitation and the quality of medical care improves over time, disease rates fall and biological resources that were once devoted to fighting off infection can be harnessed to aid brain development, spurring higher average IQs.

They support this conclusion by drawing on data from the World Health Organization on disability-adjusted life years lost disease covering 192 countries and IQ studies from 113 countries. Even after adjusting for other possible contributing factors such as income, education, changing levels of agricultural labor and climate, the correlation held true. It also helps their case that there is direct evidence of diseases affecting cognitive development. Intestinal worms, malaria and diarrhea have variously been demonstrated to have long-term effects on afflicted children.

Finally, the authors posit that there is a type of medical affliction that should rise in line with average intelligence: asthma and other forms of allergies. As these conditions are thought to be linked to immune systems that have not been challenged enough by infection, it stands to reason that a country’s allergy levels will be correlated with the average IQ of its population. This will be the next subject of their research.

There is no Big Bang

Next is a physics paper covered in the Physics arXiv Blog from the MIT Technology Review. The Big Bang is one the rare concepts from astrophysics to have succeeded in seizing the imagination of the mainstream public as it is an intuitively appealing as well as a logically sound explanation of how the universe began. However this theory has relied on assuming the existence of a mooted form of dark energy to explain the increasing rate of expansion of the universe that astronomers have observed. This is annoying as, by definition, we cannot detect dark energy and have no idea what it actually is, and because this flies in the face of the conservation of energy as ever increasing amounts of dark energy would be needed to explain the universe’s ever increasing rate of expansion.

So along comes Wun-Yi Shu of the National Tsing Hua University in Taiwan who offers an alternative model of the universe that does not require the Big Bang. According to his model, space and time are not independent entities. Rather, space and time continually converts back and forth into each other in a cyclical process with the speed of light being the conversion factor between the two. Therefore, the observed expansion of the universe is a case of mass and time being converted into space and length. When the universe inevitably contracts, the inverse happens. The universe according to this view has no definite beginning and end. Instead, there are only alternating cycles of expansion and contraction, with no singularities allowed.

Naturally, this is merely a mooted first look and it’s likely that this is just the latest of many failed alternative explanations. Currently, this idea’s biggest problem is that it can’t explain the cosmic microwave background, which among other things, manifests as static on Earth. According to the Big Bang theory, this represent the dying echoes of that first explosion, still detectable even after countless billions of years. Still, even if it comes to nothing, I enjoy reading about new ideas in physics that radically challenge the accepted status quo and admire the chutzpah behind such proposals.

Choose your car color carefully

Finally, I’ve included an article about how car colors affect the rate of car theft and why, from Vox. Ben Vollaard of the University of Tilburg examines car theft statistics in the Netherlands that finds that cars of some colors are much more prone to theft than others. He finds that the most common car colors in the country, namely black, blue and silver / grey are also the ones that thieves favor the most. The color thieves stayed away from the most was pink. None of the pink cars included in the statistics were stolen.

This raises the question of why such unusual colors serve as a deterrent to thieves. The article proposes two possible explanations. One is that cars in unpopular colors have a low resale value and thieves naturally go for the most valuable cars. The second one is that cars in bright colors tend to stand out more and thieves who steal them are more easily caught.

To determine which explanation is correct, the author looked at statistics for red-colored cars. It turns out that red was a popular color in the 1990s but is now out of fashion. If thieves truly avoided red cars because they feared the bright color would attract attention, then theft rates for red cars would have been the same in the 1990s as they are today. This turned out not to be the case as theft rates for red cars were higher in the 1990s. This suggests that thieves are primarily motivated by the resale value of the vehicle and do not fear attracting undue attention.

Apart from the educational value of learning how to properly choose the colors of the cars you purchase, I find this article to be an excellent example of the unconventional uses of economics that are in fashion. It’s amazing how far a little out-of-the-box thinking can take you.