Come again?

“HOW extremely stupid not to have thought of that!” Many statisticians, confronted with the GRIM test might find themselves echoing Thomas Huxley’s words when he read about the idea of natural selection. The GRIM test, short for granularity-related inconsistency of means, is a simple way of checking whether the results of small studies of the sort beloved of psychologists (those with fewer than 100 participants) could be correct, even in principle. It has just been posted in PeerJ Preprints by Nicholas Brown of the University Medical Centre Groningen, in the Netherlands, and James Heathers of Poznan University of Medical Sciences, in Poland.

To understand the GRIM test, consider an experiment in which participants were asked to assess something (someone else’s friendliness, say) on an integer scale of one to seven. The resulting paper says there were 49 participants and the mean of their assessments was 5.93. It might appear that multiplying these numbers should give an integer product—ie, a whole number—since the mean is the result of dividing one integer by another. If the product is not an integer (as in this…Continue reading
Source: Economist

Graphic details

A PICTURE is said to be worth a thousand words. That metaphor might be expected to pertain a fortiori in the case of scientific papers, where a figure can brilliantly illuminate an idea that might otherwise be baffling. Papers with figures in them should thus be easier to grasp than those without. They should therefore reach larger audiences and, in turn, be more influential simply by virtue of being more widely read. But are they? Bill Howe and his colleagues at the University of Washington, in Seattle, decided to find out.

First, they trained a computer algorithm to distinguish between various sorts of figures—which they defined as diagrams, equations, photographs, plots (such as bar charts and scatter graphs) and tables. They exposed their algorithm to between 400 and 600 images of each of these types of figure until it could distinguish them with an accuracy greater than 90%. Then they set it loose on the more-than-650,000 papers (containing more than 10m figures) stored on PubMed Central, an online archive of biomedical-research articles.

To measure each paper’s influence, they calculated its article-level…Continue reading
Source: Economist

Engines of creation

JUNE 22nd is the 20th birthday of “Quake”. Its release, by a Texan firm called id Software, was a milestone in the history of video games. “Quake”, a grim and gory fantasy “shoot-’em-up”, pioneered many now-commonplace features of computerised play. Its most striking innovation was its fully three-dimensional world. This was drawn by a piece of software, called a game engine, regarded at the time as jaw-dropping.

These days “Quake” looks like a muddy brown mess. Two decades of advances in processing power, allied with cut-throat competition between games designers, have advanced the art tremendously. Game engines are now a product in their own right. Besides drawing the graphics, they handle tasks like simulating physics (such as gravity, say, or object collisions) and connecting players to each other online. They are, in other words, the platforms upon which games are built. Most games companies buy them pre-made, off the shelf. And not just games companies. Game engines have become so good at creating high-quality facsimiles of reality that they are attracting the attention of firms that, until now, have had nothing to do with video…Continue reading
Source: Economist

It’s the pits

Tinker, tailor, soldier, cleaner

TO DISCOVER how to use a waste material to clean up hazardous chemicals is a notable achievement. To do so while working in a war zone is doubly impressive. But that, with a little help from some foreign friends, is just what Abdulsamie Hanano of Syria’s Atomic Energy Commission, in Damascus, has done. Over the past four years Dr Hanano, who works in the commission’s molecular-biology department, and his colleagues have developed a way to use the stones (or pits) of dates, a waste product of the fruit-packing industry, to clean up dioxins, a particularly nasty and persistent type of organic pollutant that can lead to reproductive and developmental problems, damage the immune system, and even cause cancer. Dioxins are produced mainly as a by-product of industrial processes.

Dr Hanano lit on date stones for this task for three reasons. One was that they are rich in oils of a sort that have an affinity for dioxins. The second was that, though they are not unique in this oil-richness, unlike other oil-rich seeds (olives, rape, sesame and so on) they have no commercial value. The third was that,…Continue reading
Source: Economist

Gut feelings

Bacterial protection service

ONE of the less-known problems of obesity is that obese mothers are 50% more likely than those of normal weight to give birth to children who go on to develop autism. This correlation is perplexing, but some suspect it is connected to differences between the gut bacteria of the overweight and of those who are not. One researcher who thinks this way is Mauro Costa-Mattioli of Baylor College of Medicine, in Houston. He has just published evidence in Cell that, in mice at least, a clear relationship does exist between gut flora, obesity and social behaviour. What is particularly intriguing is that the culprit seems to be a single bacterial species.

Dr Costa-Mattioli and his colleague Shelly Buffington set up a series of experiments, each of which involved feeding 100 female mice a normal diet or a high-fat diet for eight weeks, getting those mice pregnant and then examining both the behaviour and the gut flora of their offspring. To monitor behaviour, the researchers put the pups through tests that measured how long they spent interacting with strangers and with inanimate…Continue reading
Source: Economist

Gaming goes to Hollywood

See: <a…Continue reading
Source: Economist

How “likes” affect teenagers’ brains

FOR the first six months after teenagers in Colorado pass their driving test, the state bans them from carrying non-sibling teenage passengers unless someone over 21 is also in the car. It is not alone in this ageist approach. Fourteen other American states impose similar restrictions. The reason is that mountains of data show teenagers take risks more readily in the presence of their peers.

But, in today’s virtually enabled world, “presence” is a slippery concept. As a study published in Psychological Science by Lauren Sherman of the University of California, Los Angeles, and her colleagues shows, peers’ influence can travel even through something as apparently trivial as the “like” button in social media.

Dr Sherman, an expert on digital-media use and the development of the adolescent brain, was aware of many studies suggesting peer pressure can be exerted digitally, through chat rooms and messaging systems. But she also knew that little work had been done on what actually happens in the brain as teenagers engage with the technology. She knew, too, there was no understanding of how they respond to more subtle…Continue reading
Source: Economist

Turning air into stone

THIS year the world’s power stations, farms, cars and the like will generate the equivalent of nearly 37 billion tonnes of waste carbon dioxide. All of it will be dumped into the atmosphere, where it will trap infra-red radiation and warm the planet. Earth is already about 0.85°C warmer than last century’s average temperature. Thanks to the combined influence of greenhouse-gas emissions and El Niño, a heat-releasing oceanic phenomenon, 2016 looks set to be the warmest year on record, and by a long way.

It would be better, then, to find some method of disposing of CO₂. One idea, carbon capture and storage (CCS), involves collecting the gas from power stations and factories and burying it underground where it can do no harm. But CCS is expensive and mostly untried. One worry is whether the buried gas will stay put. Even small fissures in the rocks that confine it could let it leak out over the course of time, undoing much of the benefit. And even if cracks are not there to begin with, the very drilling necessary to bury the gas might create them.

A paper just published in Science offers a possible…Continue reading
Source: Economist

Bugs in the system

MICROBES, though they get a bad press as agents of disease, play a beneficial role in agriculture. For example, they fix nitrogen from the air into soluble nitrates that act as natural fertiliser. Understanding and exploiting such organisms for farming is a rapidly developing part of agricultural biotechnology.

At the moment, the lead is being taken by a collaboration between Monsanto and Novozymes, a Danish firm. This consortium, called BioAg, began in 2013 and has a dozen microbe-based products on the market. These include fungicides, insecticides and bugs that liberate nitrogen, phosphorous and potassium compounds from the soil, making them soluble and thus easier for crops to take up. Last year researchers at the two firms tested a further 2,000 microbes. The top-performing strains boosted maize and soyabean yields by about 3%.

In November 2015 Syngenta and DSM, a Dutch company, formed a similar partnership, and earlier that year, in April, DuPont bought Taxon Biosciences, a Californian microbes firm. Hopeful startups abound. One is Boston-based Indigo, whose researchers are conducting field tests of some of its library of 40,000 microbes to see if they can alleviate stress induced by drought and salinity in cotton, maize, soyabeans and wheat. Another is Adaptive Symbiotic Technologies, of Seattle. The scientists who set up this firm study fungi that…Continue reading
Source: Economist

The hole story

Instant duck pond

POTHOLES are a scourge of rich and poor countries alike. The American Automobile Association recently calculated that 16m drivers in the United States suffered pothole damage to their vehicles in the past five years. That damage ranged from punctures, via bent wheels, to broken suspensions. The bill to fix it was about $3 billion a year. In India, meanwhile, the cost of potholes is often paid in a harsher currency than dollars. There, more than 3,000 people a year are killed in accidents involving them. Yet cash-strapped governments often ignore the problem, letting roads deteriorate. In Britain, for example, some £12 billion ($17 billion) would be needed to make all roads pothole-free. Ways of repairing potholes more cheaply and enduringly would thus be welcome. And several groups of researchers are working on it.

The most common cause of potholes is water penetrating cracks in a road’s surface and weakening its foundation. This is a particular problem with asphalt surfaces. These are made from an aggregate of materials bound together by sticky bitumen. The constant pounding of traffic disintegrates the…Continue reading
Source: Economist