Archives for population



Why Are the Japanese No Longer Interested in Sex?

From the Guardian:

Japan’s under-40s appear to be losing interest in conventional relationships. Millions aren’t even dating, and increasing numbers can’t be bothered with sex. For their government, “celibacy syndrome” is part of a looming national catastrophe. Japan already has one of the world’s lowest birth rates. Its population of 126 million, which has been shrinking for the past decade, is projected to plunge a further one-third by 2060.

And:

The number of single people has reached a record high. A survey in 2011 found that 61% of unmarried men and 49% of women aged 18-34 were not in any kind of romantic relationship, a rise of almost 10% from five years earlier. Another study found that a third of people under 30 had never dated at all. (There are no figures for same-sex relationships.) Although there has long been a pragmatic separation of love and sex in Japan – a country mostly free of religious morals – sex fares no better. A survey earlier this year by the Japan Family Planning Association (JFPA) found that 45% of women aged 16-24 “were not interested in or despised sexual contact.” More than a quarter of men felt the same way.

 The article contains a number of speculations as to cause, well worth reading. At least the Malthusians will be happy.



The Academic Origins of China’s One Child Policy

In our latest Freakonomics Radio podcast, “Misadventures in Baby-Making,” we describe an academic paper by a Dutch mathematics professor that might have been one of the inspirations of the controversial One Child Policy in China.

Here’s the story: in the early 1970s, Geert Jan Olsder co-authored the paper “Population Planning; a Distributed Time Optimal Control Problem.” He saw population as a mathematical constraint problem, where an optimal birth rate could be found:

“Given a certain initial age profile the population must be “steered” as quickly as possible to another, prescribed, final age profile by means of a suitable chosen birth rate.”

The model considered the natural birth rate and mortality rate, an economic constraint, and time. And like any good empirical scientist, Olsder makes this warning in his paper:

“This paper is not concerned with the social and political problems involved in establishing the best mechanism for a program of population management….The optimal birth rate may unbalance the age distribution during the time interval concerned, which could give rise to economic and social problems.”

Read More »



The World’s Fastest-Growing Cities: Kabul is No. Five

In honor of the world’s estimated population hitting seven billion next week, Foreign Policy has compiled a list (with beautiful photographs) of the world’s seven fastest-growing cities. China and India dominate the list, but a few of the entries may surprise you. For example, number five is Kabul, Afghanistan.

“One of the oldest cities in the world, it is growing rapidly despite — or perhaps because of — the security concerns that plague Afghanistan,” writes Kedar Pavgi. “The city has 6 million inhabitants, and continues to expand at 4.74 percent a year. But the city faces serious resource shortages. By 2050, the city will need six times the amount of water it currently uses in order to quench the thirst of its inhabitants. Read More »



America, the Underpopulated?

A recent editorial in The New York Sun argues that all this political bickering about immigration among Republican candidates misses an important truth: America is actually underpopulated. From the article:

[N]ot a single Republican candidate has spoken up for the idea that America is an underpopulated country. In terms of population density, it is, at 83 persons a square mile, an impoverished country, barely a quarter of the rich density of China, which is running way behind India. America just has enormous room for population growth.

And a desperate need.

What do you think, readers? Is America under-populated? Would Montana and Wyoming, for example, benefit from a few more people?

(HT: Paul Kedrosky)



What Will Be the Impact of Seven Billion People?

On Halloween this year, the world’s population will hit seven billion — or so estimates the United Nations Population Fund. Spooky, considering we hit six billion only a little more than a decade ago. Elizabeth Kolbert offers a brief history of population growth in a recent New Yorker article:

Depending on how you look at things, it has taken humanity a long time to reach this landmark, or practically no time at all. Around ten thousand years ago, there were maybe five million people on earth. By the time of the First Dynasty in Egypt, the number was up to about fifteen million, and by the time of the birth of Christ it had climbed to somewhere in the vicinity of two hundred million. Global population finally reached a billion around 1800, just a couple of years after Thomas Malthus published his famous essay warning that human numbers would always be held in check by war, pestilence, or “inevitable famine.”

Of course, we all know that Malthus was a little off the mark. Read More »