Progress Daily

Bradford DeLong has estimated that for most of the the past 7,000 years economic growth proceeded at a steady exponential rate, with a doubling of output about every 900 years (see “Estimating World GDP, One Million B.C.–Present“). Within the past few centuries, output began doubling faster and faster (the Industrial Revolution), approaching a new steady doubling time of about 15 years. That’s about 60 times faster than in the previous seven millennia.

In the roughly 2 million years our ancestors lived as hunters and gatherers, the population rose from about 10,000 protohumans to about 4 million modern humans. If, as we believe, the growth pattern during this era was fairly steady, then the population must have doubled about every quarter million years. Then, beginning about 10,000 years ago, a few humans began to settle down and live as farmers. The resulting communities grew so fast that they quickly accounted for most of the world population (the Agricultural Revolution). From that time on, the farming population doubled about every 900 years — some 250 times faster than before.

Both eras before now switched suddenly to a new era having a growth rate that was between 60 and 250 times as fast. Both switches were completed in much less time than it had taken the previous regime to double — from a few millennia for the agricultural revolution to a few centuries for the industrial one.

If a new revolution were to show the same pattern as the past two, then growth would quickly speed up by between 60- and 250-fold. The world economy, which now doubles in 15 years or so, would soon double in somewhere from a week to a month. If the new revolution were as gradual (in power-law terms) as the Industrial Revolution was, then within three years of a noticeable departure from typical fluctuations, it would begin to double annually, and within two more years, it might grow a million-fold. If the new transition were as rapid as the Agricultural Revolution seems to have been, change would be even more sudden.

In the era of hunting and gathering, the economy doubled nine times; in the era of farming, it doubled seven times; and in the current era of industry, it has so far doubled 10 times. So if the number of doublings is similar across these three eras, then we seem overdue for another transition.

About two-thirds of all income in the rich countries is paid directly for wages, and much of the remaining third represents indirect costs of labor.

As machines become more “intelligent,” the economy would start growing much faster. We could create machine workers in much less time than it takes to breed, rear, and educate new human workers. Being able to make and retire machine workers as fast as needed could easily double or quadruple growth rates.

The cost of computing has long been falling much faster than the economy has been growing. When the workforce is largely composed of computers, the cost of making workers will therefore fall at that faster rate.

As the economy begins growing faster, computer usage and the resources devoted to developing computers will also grow faster. And because innovation is faster when more people use and study something, we should expect computer performance to improve even faster than in the past.

“Economics Of The Singularity,” by Robin Hanson

According to Joel E. Cohen, there is enough grain grown on earth to feed 10 billion vegetarians. But much of it is being fed to cattle, which are eaten by the world’s wealthy.

There may be enough acreage already planted to keep the planet fed forever, because 10 billion humans is roughly where the UN predicts that the world population will plateau in 2060. (In the late 1980s, Brown University’s World Hunger Program calculated that the world then could sustain 5.5 billion vegetarians, 3.7 billion South Americans or 2.8 billion meat-loving North Americans.)

The world’s current population, with 1,000 square feet of living space each, could fit into Texas.

A water shortage that raised prices to around $150 would make it profitable to build pipes from the polar icecaps, or desalinate seawater, as the Saudis already do.

“Malthus Redux,” by Donald G. McNeil Jr.

About one in 20 children have a group of symptoms that has come to be known as attention-deficit hyperactivity disorder (ADHD). About 60% of them carry those symptoms into adulthood. ADHD is believed to be genetic, and is associated with particular variants of receptor molecules for neurotransmitters (chemicals that carry messages between nerve cells) in the brain. In the case of ADHD, the neurotransmitter is often dopamine, which controls feelings of reward and pleasure. People with ADHD apparently receive positive neurological feedback for “inappropriate” behaviour.

ADHD sufferers are impulsive. They have trouble concentrating on any task unless they receive constant feedback, stimulation and reward. They tend to perform poorly in modern society and are prone to addictive and compulsive behaviour.

Dan Eisenberg speculated that such behavior may be advantageous for people who lead a peripatetic life. Since today’s sedentary city dwellers are recently descended from such people, natural selection may not have had time to purge the genes that cause it.

Eisenberg tested this by studying the Ariaal, a group of pastoral nomads who live in Kenya. The receptor Mr Eisenberg looked at was the 7R variant of a protein called DRD4, a variant is associated with novelty-seeking, food- and drug-cravings, and ADHD. (See “Dopamine receptor genetic polymorphisms and body composition in undernourished pastoralists.”)

The researchers looked for 7R in two groups of Ariaal. One was still pastoral and nomadic. The other had recently settled down. They found that about a fifth of the population of both groups had the 7R version of DRD4. However, the consequences of this were very different. Among the nomads, who wander around northern Kenya herding cattle, camels, sheep and goats, those with 7R were better nourished than those without. Among their settled relations, those with 7R were worse nourished than those without it.

This discovery fits past findings that 7R and a set of similar variants of DRD4 (the “long alleles”) are more common in migratory populations.

There remains the question of why 7R is found in only a fifth of the Ariaal population. One possibility is that its effects are beneficial only when they are not universal, and some sort of equilibrium between variants emerges.

“The misfits,” The Economist

The biggest investment boom in history is under way. Over half of the world’s infrastructure investment is now taking place in emerging economies, where sales of excavators have risen more than fivefold since 2000. In total, emerging economies are likely to spend an estimated $1.2 trillion on roads, railways, electricity, telecommunications and other projects this year, equivalent to 6% of their combined GDPs — twice the average infrastructure- investment ratio in developed economies.

Morgan Stanley predicts that emerging economies will spend $22 trillion (in today’s prices) on infrastructure over the next ten years, of which China will account for 43%. China has spent more (in real terms) in the past five years than in the whole of the 20th century.

Never before has infrastructure spending been so large as a share of world GDP. Even at the peak of Britain’s railway mania in the 1840s, total infrastructure investment was only around 5% of GDP; China is already spending around 12% of its GDP.

The World Bank estimates that a 1% increase in a country’s infrastructure stock is associated with a 1% increase in the level of GDP.

Goldman calculates that a 1% increase in the share of people living in cities leads to a 1.8% increase in demand for installed electricity capacity. A 1% rise in income per head leads to a 0.5% increase in demand. Putting this together, electricity capacity may have to surge by 140% in China and by 80% in India over the next decade.

A 1% increase in income per person leads to a 1.4% increase in the number of passengers travelling by air, so the number of air passengers could jump by more than 350% in China and by 200% in India over the next decade.

“Building BRICs of growth,” The Economist

Ray Kurzweil predicts that if you can live another 15 years, your life expectancy will keep rising every year faster than you’re aging. And then you can be around for the Singularity (when humans and/or machines start evolving into immortal beings with ever-improving software) a few decades later.

In 1976, when Kurzweil pioneered a device that could scan books and read them aloud, it was the size of a washing machine. Two decades ago he predicted that “early in the 21st century” blind people would be able to read anything anywhere using a handheld device. In 2002 he narrowed the arrival date to 2008. Kurzweil debuted his cellphone-sized reader this year.

In the late 1980s, Kurzweil predicted the explosive growth of the Internet in the 1990s and a computer chess champion by 1998 (a year late, it turned out).

Kurzweil makes his predictions using what he calls the Law of Accelerating Returns. More than a century ago, machines’ computing power doubled about every three years; then in midcentury the doubling came every two years; now it takes only about a year.

During the past century there has been exponential growth in the number of patents issued, the spread of telephones, the money spent on education, etc.

Exponential progress has recently begun in nanotechnology, the ease of gene sequencing, and the resolution of brain scans.

Kurzweil says that if his predictions seem overly optimistic that’s because exponential upward curves appear deceptively gradual at first.

“Scientists imagine they’ll keep working at the present pace. They make linear extrapolations from the past. When it took years to sequence the first 1% of the human genome, they worried they’d never finish, but they were right on schedule for an exponential curve. If you reach 1% and keep doubling your growth every year, you’ll hit 100% in just seven years.”

“The Future Is Now? Pretty Soon, at Least,” by John Tierney

According to a new report by Marilyn A. Brown, et al., (”Shrinking the Carbon Footprint of Metropolitan America“) each resident of the 100 largest US metropolitan areas is responsible on average for about 2.5 tons of carbon dioxide in energy consumption each year, 14% below the 2.9 ton national average.

Those 100 cities (where two thirds of the people in the US live) still account for 56% of the nation’s carbon dioxide pollution. But their greater use of mass transit and population density reduce the per-person average.

Emissions of carbon dioxide are highest in the eastern US, where people rely heavily on coal for electricity. They are lower in the West, where weather is more favorable and where electricity and motor fuel prices have been higher.

“City dwellers dubbed ‘green’,” by H. Josef Hebert

If you take Wikipedia as a unit — every page, edit, talk page, & line of code, in every language — that represents something like the cumulation of 100 million hours of human thought (according to Clay Shirkyon & Martin Wattenberg).

Television-watching represents about two hundred billion hours, in the US alone, every year. That’s 2,000 Wikipedia projects a year. Americans spend 100 million hours every weekend just watching the ads.

Imagine that people replace only 1% of the their TV time with the production & sharing of online content. The Internet-connected population watches roughly a trillion hours of TV a year. One per cent of that is 100 Wikipedia projects per year worth of participation.

“Gin, Television, and Social Surplus,” by Clay Shirkyon

Globalization has accounted for only a small share of job creation and destruction over the past few decades. According to Pankaj Ghemawat, 90% of fixed investment around the world is domestic. Companies open plants overseas, but that’s mainly so their production facilities can be close to local markets.

According to Thomas Duesterberg, the US’s share of global manufacturing output has actually increased slightly since 1980.

The chief force reshaping manufacturing is technological change (hastened by competition with other companies, foreign and domestic). Manufacturing productivity has doubled over two decades. Employers now require fewer but more highly skilled workers. According to William Overholt, between 1994 and 2004 the Chinese shed 25 million manufacturing jobs, 10 times more than the US.

“The Cognitive Age,” by David Brooks

Reading the 3bn “base pairs” in human DNA — akin to letters, encoding a total of between 20,000 and 30,000 genes that are the “words” of genetics — is getting faster as companies find quicker ways to “read” entire stretches of DNA at a time, like reading a sentence in chunks rather than letter by letter.

The cost of sequencing an individual genome is thus falling exponentially — just as the cost of hard disk space or transistors on a chip did when computing took off.

The rapidly falling cost and time needed to map your DNA:

2003
$440M
13 years to map

2007
$10M
4 years

2008
$100K
4 weeks

2012
$100*
2 days

*Forecast

“Mapping the individual - cheaply,” by Charles Arthur

Justin Wolfers and Betsey Stevenson analyzed all the major post-war happiness studies data (.pdf file here), including new data from the Gallup World Poll, which contains detailed data on subjective well-being for 132 countries in 2006. Contrary to previous researchers using less complete date, they found that: 1) Rich people are happier than poor people. 2) Richer countries are happier than poorer countries. 3) As countries get richer, they tend to get happier.

The following chart takes the average levels of satisfaction reported on the Gallup Poll’s 0-10 scale, and plots it against G.D.P. per capita (note the log scale):

The correlation between average levels of happiness and average incomes is very high — greater than 0.8.

The relationship between happiness and log income appears nearly linear. Thus, a 10% rise in income in a rich country like the USA appears to increase happiness by about as much as a 10% rise in income in Burundi — in fact, the slope appears to get steeper above $15K!

A 10% rise in income in Burundi requires one-sixtieth as much income as a 10% rise in income in the USA. Thus, even if the slope is three times as steep for rich countries as poor countries (as Wolfers & Stevenson estimate), this still means than an extra $100 has about a twenty-times-greater effect on happiness in Burundi.

“The Economics of Happiness, Part 1 & Part 2,” by Justin Wolfers