This blog is intended to go along with Population: An Introduction to Concepts and Issues, by John R. Weeks, published by Cengage Learning. The latest edition is the 12th (it came out in 2015), but this blog is meant to complement any edition of the book by showing the way in which demographic issues are regularly in the news.

If you are a user of my textbook and would like to suggest a blog post idea, please email me at: john.weeks@sdsu.edu

Saturday, November 18, 2017

Dogs Are Good for Your Health!

Thanks to Todd Gardner and several others for pointing to a great study reported on by BBCNews showing that dogs are associated with better health among their owners than among people without dogs. The analysis is drawn from a large population-based longitudinal database in Sweden and the findings were just published in Scientific Reports.
We aimed to investigate the association of dog ownership with incident cardiovascular disease (CVD) and death in a register-based prospective nation-wide cohort (n = 3,432,153) with up to 12 years of follow-up. Self-reported health and lifestyle habits were available for 34,202 participants in the Swedish Twin Register.
Their overall conclusion is as follows:
[I]n a nationwide population based study with 12 years of follow-up, we show that dog ownership is associated with a lower risk of cardiovascular disease in single households and with a reduced risk of cardiovascular and all-cause death in the general population.
Taken together, we believe our longitudinal population-wide design provides the most robust evidence so far of a link between dog ownership and health outcomes, although bias from reverse causation, misclassification and confounding cannot be excluded.
Note that the authors are careful about the direction of causation. It may be that healthier people are generally more likely to have dogs, but even if that were true it doesn't negate the possibility that dogs can improve your health.

The one caveat that I would throw into the mix is that dog ownership is not always associated with loving the dogs. Our current German Shepherd was abandoned by its owner at a high-kill animal shelter here in Southern California when he was about one year old. Fortunately for Larry Bear (our name for him--his photo from just a few minutes ago is below) and for us, he was rescued by Coastal German Shepherd Rescue, and then he "rescued" us as we gave him his forever home. He's good for our health, and we're good for his health--it's a nice combination
.


Friday, November 17, 2017

Land Grabs and Hunger in Africa

A few days ago I posed the question: Can we keep feeding a growing population? My answer was don't bet on it, and other news this week speaks to some of the problems. Yesterday Reuters reported that the United Nations now estimates that the number of hungry people in Africa rose by 10% in 2016, pushing the overall number to 224 million. The explanation given was that the combination of conflict and climate change has made it harder to grow and distribute food in the sub-Saharan region. 

Keeping in mind that Africa has the fastest growing population in the world, what happens there has a huge impact on the global hunger picture. And one of the things happening in Africa is a land grab by wealthier countries who want to increase food productivity not necessarily for Africans, but rather as a source of food for themselves. Timothy Wise of the Small Planet Institute in Cambridge, Massachusetts (and also a senior researcher at the Global Development and Environment Institute at Tufts University) has been studying these issues for some time now and his group recently sent out this summary of some of the events he has been covering:
Tim was in Maputo October 23-24 for the Trinational People’s Conference on ProSAVANA, the controversial Mozambique-Brazil-Japan agricultural development project widely denounced by local farmers and communities as a land-grab. Fifty farmers took turns lecturing ProSAVANA director Antonio Limbau that they did not want large-scale foreign investments, they wanted support for their own food production. Tim has covered the conflict since 2014 (see previous articles here and here). This year he has also researched a controversial Chinese rice project; look for an in-depth report on the project soon.
While in Maputo, Tim presented at an African Union-sponsored three-day conference on “Climate Smart Agriculture,” the new catch-all term for agricultural practices that mitigate and adapt to climate change. He was part of an ActionAid-sponsored event on agro-ecology, where he laid out the evidence supporting a transition to soil-building agro-ecological practices, in contrast to the Green Revolution practices of monoculture fed by synthetic fertilizers. Colleagues from Zambia and Malawi presented case studies, and Tim offered observations of the successful project he’s seen in Marracuene, Mozambique. (See articles here and here.)
The point is that Africa needs its land to grow food for its rapidly growing population and it needs help (meaning investments, but not ones that are essentially confiscatory) to implement sustainable methods for increasing per acre productivity. The region's population growth will not be sustainable if Africans are routinely taken advantage of with respect to their agricultural land. 

Thursday, November 16, 2017

Weaponized Mosquitos May be Headed Your Way

Malaria continues to be one of the biggest killers of humans in the world, and since mosquito bites are the method by which the malaria parasite infects a human, controlling mosquitos is a big deal. And, of course, mosquitos help spread other deadly diseases besides malaria, including dengue fever and the Zika virus. Over the years I have often blogged about both mosquitos and malaria--most recently in April of this year on World Malaria Day, when I discussed a new malaria vaccine being introduced. Last week we had yet another development, as the U.S. Environmental Protection Agency approved the release of what are called "weaponized mosquitos" in 20 U.S. states.
The US Environmental Protection Agency has given its approval for MosquitoMate, a Kentucky-based biotechnology company, to release its bacteria-infected male mosquitoes in several parts of the United States.
The company’s lab-grown mosquitoes, which it calls ZAP males, are infected with the Wolbachia bacteria, naturally occurring in many insects, but not in Aedes aegypti, a vector for viruses such as yellow fever, dengue and Zika. When bacteria-infected males mate with uninfected females, the females produce eggs that don’t hatch. In addition, infected mosquitoes are less likely to spread disease.
Entomologist Stephen Dobson, CEO of MosquitoMate, told Quartz that the company could start selling the infected mosquitoes in the summer for use by municipal bodies and individual homeowners. The male mosquitoes don’t bite, which should make the release of these insects sound less alarming. 
The 20 approved states are California, Connecticut, Delaware, Illinois, Indiana, Kentucky, Massachusetts, Maine, Maryland, Missouri, New Hampshire, New Jersey, Nevada, New York, Ohio, Pennsylvania, Rhode Island, Tennessee, Vermont, and West Virginia, as well as Washington, DC. The permitted states include mostly those with similar weather conditions to Kentucky, New York, and California, states where the company earlier conducted trials.
While companies like MosquitoMate are trying to make mosquitos less dangerous, a report today from Nature News suggests that an old-fashioned anti-malaria strategy is being brought back in Africa:
In a sea of high-tech malaria fixes — everything from drug-delivery by drone to gene-edited mosquitoes — an old-fashioned approach is saving thousands of children in West Africa, according to studies presented this week at the American Society of Tropical Medicine and Hygiene (ASTMH) meeting in Baltimore, Maryland. 
The measure, called seasonal malaria chemoprevention, involves giving children a dose of antimalarial drugs once each month in the rainy season to prevent the disease in hard-hit regions. Researchers have previously demonstrated this strategy in large clinical trials but they had feared that their positive results wouldn’t be replicated in the messy, real world, because chemoprevention requires thousands of local health workers to deliver drugs to children in villages far from hospitals, pharmacies and paved roads.
I personally have always taken anti-malaria drugs with me to Africa, and the idea that these drugs could help save children from malaria through this selective dosage strategy is very intriguing. We are still at that stage where we have employ all of the "weapons" we can. 

Wednesday, November 15, 2017

Migration Morphs Into Slavery in Libya--UPDATED

CNN has put together a very troubling report on the way in which human migration from Sub-Saharan Africa to Europe by way of Libya has morphed into not just human trafficking, but into real slavery.
Each year, tens of thousands of people pour across Libya's borders. They're refugees fleeing conflict or economic migrants in search of better opportunities in Europe. Most have sold everything they own to finance the journey through Libya to the coast and the gateway to the Mediterranean.
But a recent clampdown by the Libyan coastguard means fewer boats are making it out to sea, leaving the smugglers with a backlog of would-be passengers on their hands. So the smugglers become masters, the migrants and refugees become slaves.
As the route through north Africa becomes increasingly fraught, many migrants have relinquished their dreams of ever reaching European shores. This year, more than 8,800 individuals have opted to voluntarily return home on repatriation flights organized by the IOM.
This turn of events is probably not a surprise to the researchers at the "Human Costs of Border Control" project at the University of Amsterdam. 
On the basis of globalization theories, as well as on the basis of developments in European migration policies, we hypothesize that since 1990 migration law has witnessed a shift from migration control (reactive, focus on concrete individuals) to migration management (pro-active, focus on potential migrant populations). A second hypothesis is that the increased number of ‘irregular’ migrants dying on their way to Europe is an unintended side-effect of this shift. Thirdly, we propose that as a consequence of the shift to border management, the human rights protection previously available regarding migrant fatalities under border control, has become considerably less effective.
After ten years of work, they have just wrapped up their research, the results of which remind us that migration policies are actually matters of life and death in their consequences.

UPDATE: The Migration Policy Institute in Washington, DC has just posted a very interesting review of the changing migration policies between Spain and Morocco and between Italy and Tunisia. Reading this helps to illustrate how complicated the policy issues are with respect to migration from South to North.

Tuesday, November 14, 2017

Can We Keep Feeding a Growing Population? Don't Bet on it

In 2011, Professor David Lam of the University of Michigan was the President of the Population Association of America and in his presidential address at the Annual Meeting that year in Washington, DC, he predicted that there should be plenty of food to go around even as the world added another 4 billion people. [Like all presidential addresses, this was published later that year in the journal Demography.] Professor Lam updated some of these ideas in a recent article in the online news magazine of the International Union for the Scientific Study of Population (IUSSP). This was followed yesterday by a sort of rebuttal of that optimism from Richard Grossman, a retired gynecologist and public health physician.
As a demographer, it is appropriate that Lam should focus on humans. However, I fear that he has largely ignored the environment in which we live when he wrote this essay. I have difficulty accepting his statement: “An important source of optimism about the world’s ability to support an additional 4 billion people is the success in supporting the previous 4 billion.” My concern is that the past 4 billion have degraded natural world upon which we depend, and that this degradation will make the world much less welcoming to the next 4 billion.
If you've read Chapter 11 of my Population text you will know that I too worry about this same issue, and you won't find anything really new or exciting in what Grossman is saying. Rather, it is very troubling. Grossman also reminds us that Lam's optimism back in 2011 was subsequently challenged by Professor Stan Becker of Johns Hopkins University: 
In 2013, Professor Stan Becker challenged Professor Lam after his presidential address at the Population Association of America in 2011 in which he forecast “I expect that it [the world] will have improved in many ways, including lower poverty, higher levels of education, and plenty of food to go around” (Lam 2011:1259). Drs. Lam and Becker have a wager on food prices (collected by FAO) over the period 2001-10 to 2011-2020, with Lam predicting they will go down and Becker predicting they will go up. Half of the period of interest has passed (2011 to 2016), and prices have risen, by about 51% globally (Table 1).
And, of course, prices are going up because we have essentially used up all the available good farmland, we have to apply new and expensive technologies to get more food out of each acre of land, and we waste a lot of land and food on animals that are killed for humans to eat. 

Sunday, November 12, 2017

South Koreans Push for the Right to Choose

For several decades abortion has been a legal and important method of fertility control for women in China and Japan. Not so in South Korea, where abortion has been outlawed since 1953 except for cases of rape, severe health threat to the mother, or a severe fetal defect. This week's Economist reports on a new push in South Korea to legalize abortion. The interesting thing about this effort is that it became necessary because a few years ago a concerted effort emerged to enforce the restrictions on abortion.
[F]or a long time governments turned a blind eye to it, viewing it as simply another form of birth control. Doctors readily provided it. Many people did not even know that it was illegal to have one. To this day the government estimates that around 170,000 pregnancies are aborted every year.
But in 2010 a group called Pro-Life Doctors started reporting hospitals offering abortions to the police. Wealthy and politically influential religious groups began campaigning against the practice too. The president at the time, Lee Myung-bak, a devout Christian, vowed to prevent illegal abortions. He created a task force to ensure the law was enforced, presenting the move as a way to lift falling fertility rates. It did not work: in 2016 there were only 406,000 live births, the lowest number on record. It did lift prices though: during Mr Lee’s term, the cost of a furtive abortion reportedly rose tenfold.
Keep in mind that a relatively rapid drop in fertility has been one of the keys to South Korea's economic success. At the same time, the birth rate is only slightly below replacement level, and is higher than in either China or Japan. Thus, it is a bit of a stretch to suggest that penalizing abortions will make a huge difference in the birth rate. This is largely a humanitarian reproductive rights issue.
A recent survey found that only 36% of people want to keep abortion as a criminal offence, down from 53% in 2010. The constitutional court is due to rule soon on a challenge to the abortion law, on the grounds that it is an unwarranted infringement of women’s personal liberty. In 2012 the court voted narrowly to uphold it, but several more liberal judges have joined since then.
To the extent that religion might play a role in the abortion debate, it is interesting to note that South Korea is a country in which there is no religious majority. A Pew Research report shows that people with no religious affiliation are the largest single group (46%), followed by Christians (29%) and Buddhists (23%). The current President, Moon Jae-In is a Roman Catholic. 


Friday, November 10, 2017

How Well Can We Predict Our Own Survivability?

Having recently had my own brush with death, I was fascinated by one of the articles in the latest issue of the Vienna Yearbook of Population Research (Volume 14--2106) published by the Vienna Institute of Demography. Well, actually, they are all good articles, but the one by Alberto Palloni and Beatriz Novak caught my eye for two reasons: (1) Professor Palloni is a Past President of the Population Association of America (click here for an interview with him), and (2) we humans tend to be very interested in our potential ability to evaluate our own likely age at death.

In their research, Palloni and Novak compared people's own subjective responses about their probability of surviving to a particular age, with life table probabilities based on calculations from death certificate analysis at the national level. Their source of data for people's subjective probabilities was a set of questions asked in the Health and Retirement Study (HRS), funded over many years by the National Institutes of Health.
The HRS is a longitudinal survey designed to gather information on individuals in the U.S. from pre-retirement into retirement. The first wave’s (1992) target population included individuals born between 1931 and 1941 who were living in households, and the spouses or partners of these individuals, regardless of their ages. Out of the 15,497 individuals who were eligible to be interviewed in 1992, 12,654 respondents were actually interviewed. Since then, the individuals in this initial cohort have been re-interviewed every two years. The entire survey consists of five birth cohorts who have been incorporated into the study over time. In the present study, we examine data from the first, fourth, and fifth HRS cohorts.
Here's what they found:
We show that the subjective probabilities are remarkably close to the results of actual life tables constructed from observed data, that whites underestimate their survival chances more than blacks, that women underestimate their survival chances more than men, and that the subjective underestimation of conditional survival increases with age in all population subgroups. We find significant differences in the survival outlooks of the original HRS cohort and a more recent HRS cohort (1992 versus 2004). These differences persist after introducing suitable controls. The observed mortality differentials between smokers and non-smokers, obese and non-obese individuals, and high-education and low-education groups are quite close to those of these subgroups’ subjective survival expectations. Finally, we find large updating effects that result from recent health shocks on subjective expectations.
As the authors note, this is really an extension of the literature showing that self-rated health generally comes very close to what physicians would say about you in a physical exam. We tend to know ourselves pretty well, and tend to monitor our likely chances of survival in a reasonably realistic way. 

Thursday, November 9, 2017

Will People in Poland Start Breeding Like Rabbits?

Thanks to Justin Stoler for the link to a BBC video on a new attempt by the Polish government to get people to raise the birth rate--encouraging them to "breed like rabbits". The video also reminds us of other attempts at this, including the Danish advertisement aimed at getting young adults to think romantically and not just have sex, but to have kids.

I'm guessing that this will not be an easy sell in Poland. The country's total fertility rate dropped down to replacement level way back in 1990, and it has slowly slipped since then down to almost 1.3. The slowness of the drop has been beneficial in the sense that it has not sent huge shocks through the age structure. Poland is aging, right along with the rest of Europe, but the population aged 20-64 (working ages) has been pretty steady at about 65% of the population. At the moment there are just about as many people under 20 as there are 65 and older. The total population size peaked in 2000 at just above 38 million, and it is still above 38 million, so there is nothing to suggest pushing the panic button.

It seems likely that this attempt to raise the birth rate is meant as a pushback against complaints by the EU that Poland has refused to accept any refugees from the Middle East. The Telegraph noted a couple of months ago that the new right-wing government in Poland is not interested in accepting refugees. Since refugees tend to be young adults--often with their children--they could be seen as an alternative to native Poles raising their birth rate, but that is clearly not currently a popular option in Poland. (And, by the way, the Danes are not interested in new refugees, either...)

Monday, November 6, 2017

Guns are a Public Health Risk in the U.S.--Redux

It is painful to note that it was scarcely a month ago that I blogged about the fact that guns are a public health problem in the United States. That was in reference to the mass shooting in Las Vegas, but Sunday's massacre at a church in Sutherland Spring, Texas, has raised that issue again. Nicholas Kristof has a very good Op-Ed in today's NYTimes laying out the case--yet again. His approach is one that makes sense, and could (please!) be politically palatable both to gun-owners and non-owners--following what we did for automobiles by making them safer.
Gun enthusiasts often protest: Cars kill about as many people as guns, and we don’t ban them! No, but automobiles are actually a model for the public health approach I’m suggesting.

We don’t ban cars, but we work hard to regulate them – and limit access to them – so as to reduce the death toll they cause. This has been spectacularly successful, reducing the death rate per 100 million miles driven by 95 percent since 1921.

Take a look at the history of motor vehicle safety since World War II:
It took a long time to make cars safer, but we've done a good job of this. The sooner we start on making guns safer, the better off we will all be.
Some of you will protest, as President Trump did, that it’s too soon to talk about guns, or that it is disrespectful to the dead to use such a tragedy to score political points. Yet more Americans have died from gun violence, including suicides, since 1970 (about 1.4 million) than in all the wars in American history going back to the Revolutionary War (about 1.3 million). And it’s not just gang-members: In a typical year, more pre-schoolers are shot dead in America (about 75) than police officers are.

Yes, making America safer will be hard: There are no perfect solutions. The Second Amendment is one constraint, and so is our polarized political system and the power of the gun lobby. It’s unclear how effective some of my suggestions will be, and in any case this will be a long, uncertain, uphill process.
We cannot sit back passively and wait for things to happen. People need to talk to their members of Congress, non-profit organizations need to get involved, and the gun manufacturers need to be brought into the dialogue, just as auto manufacturers were. 

Monday, October 30, 2017

More Sleep + Less Sugary Soda = Better Heath

OK, with any luck you already know these things, but it always helps to have new research come along to remind us of these truths. The Nation's Health (from the American Public Health Association) summarizes a study published recently in the Proceedings of the National Academy of Science
We show that more than one-half of racial differences in cardiometabolic risk can be explained by sleep patterns—namely, less total sleep and lower sleep efficiency among African American than European American adults. Sleep is a malleable health behavior that is linked with characteristics of the social and physical environment and could be an effective target in national efforts to reduce racial health disparities.
Differences in sleep patterns may be attributed to increased exposure to social stresses, the study showed. Stressors associated with socio-economic status and systemic discrimination can lead to low sleep efficiency.
Although the study compared racial/ethnic groups, the lesson is true for everyone--better sleep is associated with better health. You can find out more about this by thumbing through issues of the Journal of Sleep Research--with luck it won't put you to sleep... 

Sugary sodas have been under attack for a long time and the evidence continues to mount that they push your weight up, and that is bad for your health in a variety of ways. The latest research comes from the American Journal of Public Health and uses data from a population of teachers in Mexico.
We followed 11 218 women from the Mexican Teachers’ Cohort from 2006 to 2008. Dietary data were collected using a semiquantitative food frequency questionnaire. Weight was self-reported, and waist circumference was self-measured. We used linear regression to evaluate changes in sugar-sweetened and sugar-free soda consumption in relation to changes in weight and waist circumference, adjusting for lifestyle and other dietary factors.
Decreasing consumption of sugar-sweetened soda was associated with less weight gain, and increasing consumption of sugar-sweetened soda had an opposite association. These results were similar when waist circumference was used as a measure of adiposity. The impact of changes in sugar-sweetened soda intake on weight appeared to be stronger among women who were overweight or obese at baseline relative to women who were of normal weight. Changes in sugar-free soda consumption were not associated with weight change.
Thus, if the consumption of sugary sodas increased over a two-year period, so did a person's weight. Conversely, less sugary soda was associated with a weight loss. The results were not huge, but this was only a two-year timeframe. And the fact that sugar-free sodas had no effect lends credibility to the findings.

So, drink less sugary soda, get more sleep, and, by the way, don't forget to be vaccinated against the flu. 

Sunday, October 29, 2017

Chinese Government Doesn't Want Us to Know About the Low Birth Rate

A recent story in the South China Morning Post notes that the latest Statistical Yearbook from China omits mention of the birth rate. Very suspicious!
China’s National Bureau of Statistics has been publishing the data on the “age-specific fertility rate of child­bearing women” – the measure of how many children were born to different age groups – annually since 2004.
But in the 2017, China’s statistics yearbook, which sets out the data from the previous 12 months, the bureau said it had decided to remove these figures, which help to calculate the country’s overall fertility ratio [the total fertility rate, as we would call it].
Almost three years ago, as the one-child policy was being lifted in China, I commented on the fact that demographers did not expect a rise in the birth rate, whereas the Chinese government did. Not surprisingly, the demographers appear to continue to be right.
The statistics agency’s number, which indicated a fertility ratio of 1.05 in 2015, ran counter to an estimated fertility rate of 1.6 from the National Heath and Family Planning Commission, the body that is responsible for China’s family planning policy and ruthlessly implemented the country’s one-child policy for decades. 
While the statistics agency did not explain why it stopped publishing the data, demographers said it underscored the problems with China’s official population figures.
Liang Zhongtang, a demographer who sat on the state family planning commission in the 1980s, said China’s fertility rate had failed to show any meaningful increase after the country officially rolled out a universal two-child policy in 2016, adding that could be one reason for the non-disclosure. “A gap between what the government actually got and what they had expected may persuade them to stop releasing the data,” Liang said.
If the birth rate really is still close to one child per woman, as we expect it really is, the consequences for China's age transition are clear: the aging population will continue to grow more quickly than the younger labor force, and this will create continual strains on the Chinese economy. It is not clear whether or not this feeds into the new "Xi Jinping Thought on Socialism with Chinese Characteristics for a New Era" that is now enshrined in the communist party's constitution. What we do know from the South China Morning Post story is that family planning wasn't mentioned by Xi during the recent communist party gathering. "Instead, Xi used the much milder term “population policy” and stressed that China must “enhance strategic research” into its demographics."

Wednesday, October 25, 2017

Demographic Effects of Girls' Education in Developing Countries

The National Academies Press just released a synopsis of a workshop organized earlier this year by the Population Committee of the National Academy of Sciences on the topic of "Demographic Effects of Girls' Education in Developing Countries." The workshop was headed up by Ann Blanc of the Population Council, Jere Behrman of the University of Pennsylvania and Cynthia Lloyd who is now an independent consultant but was with the Population Council for many years. The main question raised was this: Why does education have an impact on fertility? In other words, what are the causal linkages?

In general, the participants in the workshop (who were all demographers doing work in the area of girl's education and fertility in developing countries--especially in Africa) concluded that an education can change the way a girl thinks about her place in the world and this can influence her decision-making about the timing of both marriage and childbearing. At the same time, having a baby early almost always truncates a girl's education and sets her back for the rest of her life. So, the causal links work in two directions.

I read through the synopsis of the workshop looking for things I didn't already know, and the major point that was brought out that needs some consideration is the idea that the quality of education may actually be lower now than it used to be in some of the countries that were being discussed. If that is true, then the impact of education on attitudes and behaviors of young women may be less than in the past. Still, however, I saw nothing to suggest I should modify the following summary that you will find on page 207-208 in Chapter 6 of the 12th edition of my text:
It is nearly axiomatic that better-educated women have lower fertility than less-educated women in any given society. It is the identification of this kind of fertility differential that helps to build our understanding of reproductive dynamics in human societies, because it causes us to ask what it is about education that makes reproduction so sensitive to it. In general terms, the answer is that education offers to people (men and women) a view of the world that expands their horizon beyond the boundaries of traditional society and causes them to reassess the value of children and reevaluate the role of women in society. Education also increases the opportunity for social mobility, which, in turn, sharpens the likelihood that people will be in the path of innovative behavior, such as fertility limitation, that they may try themselves. Indeed, the role of education is so important that demographers at the Vienna Institute of Demography have created a whole set of population projections incorporating trends in educational attainment as a predictor of fertility levels.

Sunday, October 22, 2017

The Demographics of Not Moving to Where the Jobs Are

There seems to be general agreement that Donald Trump's base of support are people who feel they are being left behind by the process of globalization and they want some change. It seems highly unlikely that Trump's proposed tax cuts will help those people, but this week's Economist takes a stab at the problem. 

The general pattern in the past in most countries of the world has been for people to go where the jobs are. My wife's grandfather migrated from Denmark in the late 19th century because there were no jobs there, but there was a chance to be a successful farmer in the American midwest. In my lifetime, my family certainly moved for economic reasons. During the first 12 years of my life, we lived in two different cities in northern California, three cities in Oregon, and one city in Arizona before settling down in San Diego. But Americans are moving less than they used to, according to Census data assembled by the Economist (see below). 


The Economist suggests that several demographic factors may help to understand this slowing of migration. There are now many more two-earner households, making it harder for couples to move (or even to decide where to move if they are going to move). At the same time, people may have older parents who are aging in place and who expect or at least hope that their children and grandchildren will be close enough to help them out. Another major impediment to movement is the high cost of housing in almost all of the urban places that are home to the superstar companies. The higher wages in those places may be offset by the cost of living there. There is also the fact that many unemployment and welfare benefits are place-specific. If you move, you lose those benefits, thus reducing the incentive to move since most people tend to be risk-averse.

The principal suggestion for change proposed by the Economist amounts to local economic development. This could involve a public-private partnership to invest in new types of businesses where globalization has left a labor force looking for work. Going along with this could be an investment in local community colleges geared toward teaching people the skills that these new companies need for success. This is so crazy it might just work.

Friday, October 20, 2017

How Many Births Were Averted in China by the One-Child Policy?

My thanks to Stuart Gietel-Basten for pointing to a story in Science magazine by Mara Hvistendahl about a controversy brewing over how many births were averted in China by their one-child policy.
A new study of China’s one-child policy is roiling demography, sparking calls for the field’s leading journal to withdraw the paper. The controversy has ignited a debate over scholarly values in a discipline that some say often prioritizes reducing population growth above all else.
Chinese officials have long claimed that the one-child policy—in place from 1980 to 2016—averted some 400 million births, which they say aided global environmental efforts. Scholars, in turn, have contested that number as flawed. But in a paper published in the journal Demography in August, Daniel Goodkind—an analyst at the U.S. Census Bureau in Suitland, Maryland, who published as an independent researcher—argues that the figure may, in fact, have merit.
Now, to be honest, I'm not sure that Goodkind's study is "roiling demography," but the paper is, in fact, written in a somewhat contentious style because it is obvious that Goodkind knows that his analysis will likely be unpopular. To be sure, he notes explicitly that his conclusions are different from those of a lot of people, including Stuart Gietel-Basten, and Mara Hvistendahl who wrote this story for Science. 

If you have read Chapter 6 of my book, you will know from Figure 6.9 (see below) that the drop in fertility was very similar in China (where the one-child policy was implemented in 1979) to that in Taiwan, where there was no such policy. 


The Taiwanese are culturally very similar to those in mainland China and, despite the fact that economic development may have taken off a bit earlier in Taiwan than on the mainland, the two countries were already on the same downward fertility path before China implemented its one-child policy. Goodkind tends to dismiss that argument in his paper, preferring to believe that the differences in economic development were more important than the data seem to suggest. Another major issue that I have with the Goodkind paper--that no one seems to have noticed--is that he assigns too high a TFR to China in 1970, thus artificially creating a more rapid decline in fertility in that country than the UN data (which he claims to have used) would suggest.

My reading of Goodkind's paper is that it is much ado about nothing. While one may question the editors of Demography as to whether it should have been accepted for publication, it at least reminded us that there's nothing to see here folks. The one-child policy was a human rights disaster and, in my view, was not necessary to the drop in fertility in China. The Chinese were going to avert those births with or without that policy.

Wednesday, October 18, 2017

Can Movies and TV Programs Lower Egypt's Fertility?

Fertility has been going up, not down, in Egypt over the past few years, as I have blogged about twice over the past two years (here and here). A paper just published in Demographic Research by researchers at the Wittgenstein Centre for Demography and Global Human Capital in Vienna analyzes the available data--especially from the Demographic and Health Surveys--and comes to the following conclusion:
We find that well-educated women between 20 and 29 years lack labour market opportunities. They may have preponed their fertility. Fertility could start declining again once the labour market situation for women has improved. On the other hand, the family model of three children is still widespread in the country.
I admit that I have never used the word "prepone", but it is the opposite of "postpone" and it makes sense in this usage. In a footnote in the paper, the authors indicate that the Egyptian government was trying to figure out what to do in order to lower the birth rate. My thanks to Abu Daoud who found a story about one of the things being tried--movies and TV programs.
In announcing the results of Egypt's 2017 census on Sept. 30, President Abdel Fattah al-Sisi also identified major issues surrounding the population that has grown past 100 million: early marriage, insufficient housing and, most important, overpopulation. He said, “We must face these flaws in society in collaboration with civil society and media.” His reference to the media gave newspapers and websites the green light to analyze the potential of the media as well as the film industry in confronting overpopulation in the country.
Overpopulation and problems associated with it, such as higher costs of living and uncontrolled urbanization, have long been on the agenda of the Egyptian cinema, along with issues that are hampering the lowering of birth rates, such as a rejection of birth control.
One of the challenges here is that the government has to back up any influence that the media might have by making family planning programs readily available to couples. And, of course, there has to be recognition that getting women back to work is a key element in lowering fertility. Even in urban areas, fertility remains higher than one might expect. More than a decade ago, my colleagues and I published an article on fertility in Cairo, in which we noted that:
Fertility transitions are historically thought to have started in cities and then spread to the rest of the country. This would suggest that in Egypt we would find that Cairo was well ahead of the rest of the nation in its fertility transition. The data suggest otherwise and highlight the fact that many parts of Cairo are still experiencing high levels of fertility.
There is still a long way to go to lower fertility in Egypt, but the country desperately needs to slow that pace as soon as possible--since it is, among other things, a nation facing potential water scarcity and the dangers associated with that. 

Tuesday, October 17, 2017

The Demographics of Water Scarcity

Many thanks to the folks at Population Matters for pointing to a report detailing the impact of water scarcity on youth unemployment and migration. The story comes from the International Institute for Sustainable Development and refers to analyses recently undertaken by UNESCO's World Water Assessment Program.
It finds close links between the impacts of water scarcity and migration patterns in regional hotspots including in the African, Mediterranean, South Asian and East Asian regions. The report also shows that water availability and quality impacts both youth employment and social stability.
The publication finds that growing climate variability affects water resources and the availability of jobs for youth, especially in arid and semi-arid regions. While the jobs most affected by water scarcity are in agriculture, other affected sectors include animal husbandry and fisheries. Populations migrate as a way of adapting to the lack of both water and employment opportunities.
The story has a link to a downloadable version of the report, which seems well-researched and referenced. Although it is not emphasized in the report, we know that the underlying problem here is population growth. With respect to Northern Africa, for example, the report highlights the propensity for conflict in places like MENA (see the map below) where water scarcity is combined with rapid population growth:
The figure also shows the hotspots of water-related disputes in the Mediterranean and North Africa (MENA) region, e.g. Jordan River, the control of the water resources of the Golan Heights or of the Litany River (Chazournes et al., 2013). Other conflicts among riparian countries are related to the allocation of the water from the Nile (Veilleux, 2015) and the downstream impacts of the Turkish Southeastern Anatolia Project (GAP) (Hommes et al., 2016). Often, these conflicts are caused by the high and intensive use of water in agriculture (in 2000, amounting to 63-79% of total water usage in North Africa) in a context of endemic water scarcity, which leaves other sectors and household water scarce. Notwithstanding, food security is in peril as population growth – coupled with constantly decreasing water flows since the 1960s – has in fact required an ever growing water usage in agriculture. The current situation is symptomatic of a low-adaptive capacity to climate change (Brauch, 2011).

Keep in mind that people have been thinking about these connections for a long time. In particular, I have mentioned in Chapter 1 of my book, as well as in blog posts, that Thomas Friedman of the NYTimes has linked water scarcity and population growth to the civil war still going on in Syria. 

Monday, October 16, 2017

The Plague is Still Upon Us

Mention of the plague usually brings up mental images of the Black Death (the bubonic plague) in the Middle Ages, the high mortality of which brought important demographic changes to a lot of villages in Europe and elsewhere. But the disease is still walking amongst us, as a story by Reuters today points out.
A probable case of plague in the Seychelles, imported from Madagascar, is believed to have sparked the Indian Ocean country’s first outbreak of the disease, the World Health Organization (WHO) said.
Plague, which is mainly spread by flea-carrying rats, is endemic in Madagascar. A large outbreak has killed 57 people since late August, according to the U.N. agency, the first time the disease has appeared in non-endemic urban areas, including in the capital Antananarivo.
Seychelles health authorities reported a probable case of pneumonic plague on Oct 10 in a 34-year-old man returning from a visit to Madagascar, the WHO said. “The patient continues to be hospitalized in isolation until completion of the antibiotic treatment. He is currently asymptomatic and in stable condition,” the WHO said.
Nearly 70 percent of cases in Madagascar have been pneumonic plague, a form spread human-to-human that is more dangerous than bubonic plague and can trigger epidemics. The pneumonic form invades the lungs, and is treatable with antibiotics. If not treated, it is always fatal and can kill a person within 24 hours.
Most of us have never been either to Madagascar or the Seychelles, but that doesn't mean we are immune to the risk of the plague. The US Centers for Disease Control reports that an average of 7 cases per year are reported each year in this country. Note also that while the bubonic plague is usually transmitted by fleas feeding on infected rats, pneumonic plague can be directly passed from one human to another--no fleas or rats required.

Sunday, October 15, 2017

Dan Brown--Novelist and Demographist

I have admitted before that I am a fan of Dan Brown and I always look forward to the release of his books--the latest of which is Origin. When his novel Inferno came out in 2013, I blogged about it because the theme of the book was about the threat of global overpopulation (as I note on page 8 of the 12th Edition). He refers to Malthus as a "demographist" and I had never heard that term until Dan Brown used it. A Google search suggests that it is a synonym for demographer, but I think I am going to be a little more nuanced. A demographer is someone who has an academic background in the field of demography and teaches and/or does research on demographic issues. By contrast, I am going to label as a demographist those who use demographic ideas and information without necessarily having a lot of background in the field of demography. That is not a bad thing; it is just a different thing. 

So, by that definition, Dan Brown is a demographist, along with being a brilliant novelist (and of course it doesn't hurt that his protagonist is a college professor!). His novels take place in real places that he has obviously carefully researched, and with real substantive themes, typically related in some way to religion. I thought about that, in fact, when on page 29 of Origins, Brown describes atheists as "one of the planet's fastest-growing demographics." Based on reports from Pew Research, I'm guessing that this is not an easy statement to fact-check, but the data do seem to suggest that the proportion of people in the U.S. who say they are atheists is growing. The number is larger if you more generally refer to people with "no religion" (which doesn't necessarily mean they don't believe in God). 

Interestingly enough, the "culture clash" between atheists and followers of traditional religions that forms the theme of Origins is taking place in Spain, and much of the action occurs in Barcelona--in Catalonia--a current hotbed of culture clashes, as I recently discussed.

Overall, then, reading Dan Brown novels is another example of how demography underlies everything in the world, whether we realize it or not.

Thursday, October 12, 2017

Inside Demography--An Interview with Andrew Cherlin

Dr. Andrew Cherlin is the Benjamin H. Griswold III Professor of Sociology and Public Policy at John Hopkins University, and is a Past President of the Population Association of America (PAA). He is one of the world's foremost family demographers--widely published, cited, and quoted. He has appeared in numerous of my blogs over the years, starting in 2010 and most recently just a couple of weeks ago.

Last April he was interviewed by members of the PAA History Committee (which I chair) during the PAA's annual meeting in Chicago, and we now have this interview available online at the website of the PAA. One of the important themes in Dr. Cherlin's work over the years has been to bridge the gap between academic research and public policy. Here is an excerpt from page 18 of the interview:
The recent development that I see as most productive among policy people is an agreement among conservatives and liberals that both economics and culture make a difference.
In the economic realm, people with college degrees are the winners in our globalized and automated economy. And they’re the ones who have a marriage-based, stable family life these days. What we need to do is help the people who are not the winners, help them by getting them better educated, not necessarily college degrees for all, but community college training and other apprenticeship-based programs. That’s what we need to do.
On the cultural level, I do think there is a role for stressing the importance of stability in family life. And there is nothing wrong with the liberals doing that. So we need to think about both economic and cultural ways to lessen the class divide that in 2017 seems so strong among American families.
In my view, this is the one of, if not the, most important reason for doing demographic research--to improve our understanding of how the world is working, so that we can do our best to improve life for all humans. 

Wednesday, October 11, 2017

Will Malaria Ever Be Gone From Africa?

Malaria has been one of the biggest killers of humans over the centuries, and an enormous amount of international effort has gone toward eradicating the parasites and the mosquitos that carry the parasite from one victim to another from the earth. The mosquitos (the vectors) flourish especially in warm, wet weather, so it is the mid-latitudes in which malaria is most prevalent, as you can see from the map below:



The most deadly of those parasites is the Plasmodium falciparum, which is prevalent in sub-Saharan Africa. There is probably no researcher in the world who has done more to track and map malaria than Robert Snow at Oxford University, and in the latest issue of Nature, he and his colleagues have traced the spatial spread of malaria across the face of Africa for the past 100 years. Take a look at the map below and see if you can spot a trend:

The change over time is, sadly, not so obvious, as Snow and his colleagues discuss:
The reduction in malaria transmission intensity has not occurred equally between countries or within countries (Fig. 1)[see above], with more substantive declines and ‘shrinking of the map’ occurring at the margins of the historical range of P. falciparum transmission than in the heartland of Africa’s most efficient vector species, Anopheles gambiae sensu stricto and Anopheles coluzzii. This heartland forms a densely populated belt from West Africa through Central Africa toward Mozambique, and represents the most severely impacted area of the contemporary malaria-endemic world: it was ignored after 196017, 18 and risks being ignored today19. Our previous and current armoury of interventions has not eliminated malaria in this part of the world, and there is little indication that it will do so in the foreseeable future.
The take-away here is that we cannot be complacent. There is a lot of work to do to dramatically lower malaria rates in Africa and we cannot stop trying. 

Tuesday, October 10, 2017

Catalonia is Important to Demographic History

One of the hardest things that humans do everywhere in the world is to get along with people whose culture is different than theirs. Spain has a long history of culture clashes and the most recent is the referendum in Catalonia--in northeastern Spain--to become independent of Spain. The difference between Catalonia (whose regional capital is Barcelona) and the rest of Spain lies at the heart of our current understanding of the demographic transition. On page 85 of the 12th edition, I note that:

In the early 1960s, J. William Leasure, then a graduate student in economics at Princeton [and subsequently a Professor of Economics here at San Diego State University], was writing a doctoral dissertation on the fertility decline in Spain, using data for each of that nation’s 49 provinces. Surprisingly, his thesis revealed that the history of fertility change in Spain was not explained by a simple version of the demographic transition theory. Fertility in Spain declined in contiguous areas that were culturally similar, even though the levels of urbanization and economic development might be different (Leasure 1962). At about the same time, other students began to uncover similarly puzzling historical patterns in European data (Coale 1986). A systematic review of the demographic histories of Europe was thus begun in order to establish exactly how and why the transition occurred. The focus was on the decline in fertility, because it is the most problematic aspect of the classic explanation. These new findings have been used to help revise the theory of the demographic transition.
Those provinces that caught Bill Leasure's eye were especially the ones in Catalonia. Compare the map below of marital fertility rates in 1950 in Spain [from one of Leasure's publications] with the regional linguistic map of Spain [reproduced in a paper by Ron Lesthaeghe and Antonio Lopez-Gay]:




In the Catalan-speaking areas, marital fertility was lower than elsewhere and this was due partly to the fact that urban and rural fertility rates were both low. Elsewhere in Spain the birth rates followed the expected pattern of being higher in rural than in urban areas, but Catalonia was different. This caused demographers at Princeton at the time to rethink their approach to the demographic transition in order to take culture--not just economics--into account. Current demography theory is much more sophisticated (and complex) as a result.

Monday, October 9, 2017

Cereal Production Exceeds Population Growth--For Now...

Max Roser at Oxford does a magnificent job of putting data together to help people understand what's happening in the world, and one of his group's recent blog posts (by Hannah Ritchie) relates changes over time in cereal production to population growth. The tension between population and food was at the heart of Malthusian thinking and, to be frank, if were still back in the late 18th/early 19th century of Malthus's day, we would almost certainly agree with Malthus' view of the world. As I detail in my book, two important things have happened since then: (1) we have figured out how to control both mortality and fertility; and (2) we have figured out how to grow more food on an acre of land. Here's a graph of recent trends (which is interactive if you go there directly):


Cereal production accounts for more than half of the global caloric input (including cereals that are fed to animals that are then slaughtered for human consumption) and its production has increased faster than the population has grown. This is due almost entirely to agricultural intensification (more yield per acre), rather than extensification (we are already farming all of the good land).

Of course, we don't know how long this relationship will last--and that is the critical issue. As Ritchie notes in her blog:
The adoption and success of the Green Revolution has not been consistent across the developing world. Sub-Saharan Africa (SSA) has been a region of particular concern in terms of food security. Despite making significant progress in reducing hunger in recent decades, undernourishment in Sub-Saharan Africa remains the highest in the world (with almost one-in-five people living there defined as undernourished). 
In the chart below we see that SSA’s cereal production has been unable to keep pace with population growth. Despite an increase in cereal output of around 300 percent, per capita output has been declining. Overall, we see much greater emphasis on agricultural expansion in SSA, increasing by 120 percent since 1961—approximately equivalent to the total area of Kenya. Relative to Asia and Latin America, SSA’s improvements in yield have been much more modest (increasing by only 80 percent).
Since Africa has the world's most rapidly growing population, the fact that cereal production is lagging behind population growth is a very poor omen for the future, no matter how rosy the current global situation may seem. We have to stay real about this.