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July 12, 2003
If, as I suspect, Israel becomes an untenable state for Jews in future generations because of the growth of the Arab citizenry because of the latter's high birthrates (20% of the population now, I don't think that Jews would be comfortable if they grew to more than 30%, which it seems like they will barring another infusion of Jewish immigrants like the post-Soviet one or a sharp drop in Arab birthrates), I have always believed that the United States would be the number one destination for the Israeli Jewry fleeing the sinking boat of the "Jewish" state. But now I wonder, Germany has a problem with an aging native population, and a growing hostile Muslim minority, perhaps an influx of Jews could serve as a nice counterweight to the latter.
Just some heterodox ideas.
July 11, 2003
Genes are definitely in the house
On a related note, Future Pundit notes that individual DNA sequencing may become affordable rather soon.
They say the hardest thing to say is 'sorry', but actually it is 'I was wrong'.
However, having read Keith Devlin's article, I must admit I was wrong about Monty Hall. Colour my face red! Just as well I didn't take that bet...
I console myself with the thought that some of the people who got it right seem to have cheated by searching the web for the answer, as shown by the uncanny similarities between their comments and Devlin's article.
Or maybe it's another of those billion-to-one coincidences...
South African Census
The Economist has an interesting piece on the +'s & -'s of the new South Africa seen through the lens of the recent census. The article can be found in the extended entry....
Who are we?
FIFTEEN officials died counting South Africans in the census taken in October 2001, at least four of them from gunshot wounds. Many also had to face the dogs and electric fences of white residents unwilling to answer questions. The violence and the fear help explain the census results, published this week. These suggest that the white population is shrinking fast as a share of the total: from 10.9% in 1996 to 9.6% two years ago. The numbers speaking Afrikaans or English as a first language are also sharply down. English is now only the fifth most popular language.
Statisticians say that real emigration since 1996 is much higher than the official rates. Judging by immigration reports from Australia, Canada, America, New Zealand and Britain, more than 1m white South Africans (out of about 5m) left the country in the past few years.
The census also shows that 41.6% of adult South Africans lacked formal work in 2001, a rate much higher than the official figure of about 30% and sharply worse than it was in 1996. Among blacks, one in two lacked a job.
But, in other ways, many things have improved under democratic rule. On average, South Africans are better educated, slightly richer, and better housed, lit and heated than they were in 1996, though the averages hide persistent inequality. People also have more telephones, fridges, radios, computers and cars. They also have more neighbours. The overall population rose from 40.5m to 44.8m in 2001, up 10%.
Some of that rise is explained by migrants from nearby countries such as Zimbabwe. And the true total would probably be much higher if all illegal immigrants were included in the census. But counting people who squat in rough spots such as Johannesburg's Hillbrow is even more dangerous than braving the rottweilers of the white suburbs.
The Day Care Curve
Michelle Malkin is justifiably horrified by a spate of hot car deaths involving young children in daycare centers. She tries to tie it into her theory of how Americans are indifferent to their children, but I'd be interested to know the average IQ of low-level daycare workers (i.e. the one that perform the actual childcare). Among my friends, relatives and aquaintances, women of average or better intelligence who want to work with children become teachers, social workers, child psychologists etc. The lousy pay assures that few people who are smart enough to earn a college degree will stay in the profession. This might create pressure for more courses to qualify for state certification, but I'd rather see the standardized test scores, along background checks, for anyone minding my child. But I'm sure NO state certification exam will include an IQ test.
July 10, 2003
Blood, sweat, and duende
There has been some recent question about my ethnicity, with godless saying that I am of Iberian Spanish descent, and razib saying that I am Irish American. In fact, they are both right, but just so I don't get pigeonholed I'll be thorough about the crazy quilt that is my genetic heritage. On a board full of high caste South Asians, Jews and Malaysian Chinese, I may be bested only by David in gene pool diversity.
My mother is (ethnically at least) an archetypal Georgia cracker: Heavily Welsh and English with a little Cherokee thrown in for kicks. My paternal grandfather was 100% Irish, a computer nerd before his time. My paternal grandmother was from New Orleans, and her background was a patchwork of German, French, and European Spanish. The Spanish part came from a Galician ship's carpenter who settled in Cuba and had sons who left the country for better prospects (we actually found some distant relations in a Mexican Gulf Coast City). But anyway, New Orleans was the only big city on the Gulf in those days, and that's where this enterprising fellow went and begat a son who sired my beloved grandma. As far as I know these Cubans were 100% white. They certainly looked it, as they were all blue and grey eyed with blond to reddish hair. So I am English, Welsh, Native American, French, German, Spanish and Irish. Probably a few other things as well, but that's about as much as we know. Luckily I don't care about ethnic twaddle because I could get mortally offended on behalf of ANY of these folks!
Probability & Psychology
Let's play a game. Feel free to answer in the comment box. If you're familiar with the problem, don't give it away, but if you figure it out, please do. Please don't Google it either, I'll put up the link tomorrow afternoon.
The Monty Hall Problem
On the old television game show Let's Make a Deal, there was a segment where the host, Monty Hall, would present a contestant with three doors. Hidden behind one of these doors would be a prize and if the contestant guessed the right door he won the prize. A fairly simple guess game with a 1 in 3 shot of pay-off. Every now and again though, Monty would make things a little more interesting by giving the contestant an additional choice. After the contestant had picked one of the three doors, Monty would then open one of the other two unselected doors which he knew to be empty. He would then ask the contestant if they would like to remain with their first choice or switch over to the remaining unopened door.
The question is - In such a scenario would a contestant increase their chances of winning if they a) stick with their original choice, b) switch to the remaining unopened door, or c) it doesn't make a bit of difference either way?
Update with answer:
Well, a few brave souls in the comment box answered with the intuitive yet wrong answer of 'it doesn't matter either way', knowing full well that something had to be up or the question probably wouldn't have been asked ("who was buried in Grant's tomb" trick trick questions not withstanding), but no one got obstinate, like I was really hoping for.
The best way to illustrate this, as Sliggy mentioned in the box, is through extreme exaggeration. What if instead of three there were a billion doors you had to choose from, and the prize was behind only one? Your odds of picking the right door on one try are now 1 in a billion, which is to say zero. But now let's say after you pick Monty Hall goes through and opens all those millions of empty doors, except for one, and asks you if you want to switch. The only way for that other one not to be the right door is if you picked the 1 in a billion door on your first shot! . . . So still think it's 1 in 2?
I came across this problem on the evo psych discussion group in an article linked here. What interested me is the puzzle, yes, but perhaps more so the way in which people are drawn towards intuitive answers (and how that knowledge might be useful), and how accounts of this puzzle, with amusing consistency, always seem to indicate stubborn and/or angry reactions to the information (google it and see what I mean). Take this from the article:
Indeed, some individuals I have encountered are so convinced that their (faulty) reasoning is correct that when you try to explain where they are going wrong, they become passionate, sometimes angry, and occasionally even abusive.
And, just b/c we're Gene Expression, I'll quote Charles Murray on it too:
. . .you should know for future reference that, stuck at a boring dinner party, you can create instant chaos, and sometimes rupture long and close friendships, by introducing the Monty Hall problem.
Wait, I gave up too soon, it appears Burbridge refuses to submit!:
" . . . but the probability is still equal for each door. By opening a door, he gives you information about where the prize is not, but he gives you no information about where among the remaining options it is. Therefore there is no advantage in switching from your original choice.
The title of my post has been justified. Score!! :P
July 09, 2003
Is Thabo Mbeki a moron? Or are we seeing what we want to see?
I recently linked to an article that noted that the ANC leadership is disproportionately Xhosa, Mandela and Mbeki's tribe, while their political rival the Inkatha Party is dominated by Zulus. Another point is that the South African province most devestated by HIV-AIDS has been KwaZulu-Natal, while the Xhosa areas have been effected to a milder degree . It is often asked why an intelligent and cosmopolitan man like Mbeki would allow his own people to die because of his fixation with bizarro-theories of AIDS and even more bizarro-cures. There are a few assumptions at work here though, in the most liberal interpretation, Mbeki is president of all South Africans, white to black (and all shades in between). A more realistic one is that he represents black South Africans who are given voice through the ANC. Finally, another view is that the ANC is the tool of the Xhosa elite, princes like Mandela et al.
In weighing the cost vs. benefit of battling AIDS head on, breaking social taboos in talking about sexual relations as well as draining his budget in the face of enforced neo-liberalism from the international community, I wonder if Mbeki wonders if perhaps AIDS is not a "Zulu problem." I am not suggesting ethnic chauvanism is the main reason, or even one he explicitly considers, but how many of Mbeki's close friends are Zulu? (his best friend is supposedly an Indian man) How many of Mbeki's family members have married Zulus? How many live in KwaZulu-Natal?
The outside world might see Mbeki as a black man, but perhaps he sees himself as a Xhosa prince, and makes his decisions appropriately. AIDS is decimating South African society, true, but it almost certainly also further crystallizing the Xhosa hold on power and enabling relative Zulu decline.
 Circumcision is given as the main reason for the difference-Xhosa's practice it, Zulus do not.
Individual impact of affirmative action
Here is an excerpt of a testimony toward the reality of the negative stain that affirmative action has left on a Stanford law professor (Marcus Cole) over at Volokh Conspiracy:
For something similar, check out this page on Jon David Farley, a black mathematician. It states, "He graduated summa cum laude from Harvard University in 1991, where earned 29 A's and 3 A-'s." (not my bold-faced, they are present in the original!) Also, check out this page dedicated to black mathematicians.
This illustrates the trade-off between individual attainment and group achievement-I bold-faced that professor Cole teaches at Stanford because I wanted to highlight that he is not a typical individual, let alone a typical black American. Men like Marcus Cole will and do succeed no matter their race. On the other hand, I think we can admit that if affirmative action ended today, there would be far fewer blacks in the commanding heights of academe. That is the price that we would have to pay for Marcus Cole's self-esteem.
I say this not to belittle the pain Marcus Cole feels, but to remind ourselves that in trading in their individual self-respect black Americans have created a decent sized middle class, for only 1 out of 4 blacks lives the stereotype of the underclass lifestyle today. It might be harsh to state that black Americans have sacrificed their self-respect, but I believe Marcus Cole's assessment is an accurate reflection of reality in how others perceive high achieving blacks, insofar as they will always be high achieving blacks, rather than just high achievers. I myself live at the other end of the antipode of group evaluation, the moderate success of my group (South Asians) often gives people the immediate perception that I am intellectually nimble & technically oriented (or that I drive a cab!). I have known Asian Americans who aren't good at math or straight A students who would complain that they have to live up to group expectations and deal with daily disappointment from acquaintances who quickly realize they aren't geniuses.
The evaluation and legal organization of our citizenry along group lines has individual effects. There are costs and benefits to any given decision-those of us who disagree with affirmative action must admit those costs, and those who revel in the diversity that America's current status quo allows should take time out to reflect on the individual costs that they might never have to bear.
I've just been reading Bryan Sykes's 'The Seven Daughters of Eve'. It turned out much better than I expected. The publicity for the book emphasises the fictionalised reconstruction of the lives of the 'daughters' - Ursula, Xenia, etc - but fortunately this turns out to be a small and unimportant part of the book.
Most of the book is a very clear and readable account of the development of ancestry tracing through mitochondrial DNA. I thought I knew a bit about this already, but I understood it much better after reading the book.
The other big theme is the conflict between Sykes's thesis, based on Mito DNA, that the bulk of European ancestry is paleolithic, and the Cavalli-Sforza doctrine, based on principal components analysis of nuclear DNA, that the bulk of it is descended from neolithic immigrants from the middle-east. According to Sykes's account, Cavalli-Sforza has finally conceded that the 'paleolithic' element is much larger, and now claims that this is consistent with what he said all along! Is this right?
Just a few grumbles about the book: (a) no notes or bibliography (b) the fictionalised reconstructions don't seem to take much account of modern hunter-gatherer societies, e.g. their marriage and kinship customs, and (c) the usual politically correct flapdoodle about the 'nonsense of any biological basis for racial classifications' (page 359 in the Corgi edn.), when all he really means is the platitude that races are not 'pure' and sharply differentiated. Well, of course not.
July 08, 2003
no 'safe' time to avoid pregnancy
For 50 years, doctors have believed that about a dozen follicles, or egg sacs, grow at one time during a woman's menstrual cycle. From this group, only one follicle actually bursts and releases an egg, while the others shrivel and die.
Why archaeology isn't always taken seriously
Proximate vs. Ultimate
You have two brothers. Brother A & brother B.
A has an IQ of 115 while B has an IQ of 85. A tends to be a "thinker" while B is more of an impulsive "doer." A becomes an accountant. B becomes a roofer.
A saves much of his salary, finds himself a long term g/f and marries her when they are both around 30 & settled in their careers. They have one child, who they send to private schools and a private university who doesn't have to worry about financial needs for the first 25 years. Additionally, A's child will have a nice estate after A & his wife die because the parents saved and invested wisely. A is very happy with his life and looks forward to a comfortable retirement.
B goes from paycheck to paycheck, has two marriages and two children by each marriage. He can barely support his kids, between rent, bar-tab and child support. His children don't have any money for college at 18 so they either work or rack up large loans. The family is generally a mess and B hasn't even had time to think about the idea of retirement even though his back his killing him after all his years working on roofs.
Who is planning wisely? Who is making the "best" decisions? Certainly almost all of us would prefer A's situation. But while A has one child, B has four. In ages past someone like B might not have had the means to keep even one child fed, and so not had any progeny. But in our era of plentitude (in the West) infant mortality is low. Ultimately, B may have more descendents than A.
Though A is making the "wise" proximate decisions when viewed on the individual and familial scale, it might be strange to think that B is displaying the wisdom of evolutionary ages.
Human Biodiversity makes the Big Leagues
A dustup over Dusty Baker's physiological assessment of certain Cubs. Baker stands by his assertion that black and Hispanic players can take the heat better than whites. Great defense: "I'm not playing the race card. I'm telling it like it is," Baker said.
July 07, 2003
gender and writing style
"According to a team of computer scientists, we give away our gender in our writing style."
July 06, 2003
I'm an addict
Article on information addiction.
POPULATION FALLACIES: PART 3
This is about death.
The crude death rate in a population is the number of deaths per head (or per thousand, etc) in a given period. As with the crude birth rate, it has its uses, but it is seriously affected by the age structure of the population.
For most purposes it is more useful to consider age-specific death (mortality) rates, i.e. the proportion of people in a specified age group who die in the given period. Mortality rates are also used to estimate ‘life expectancy’. The term ‘life expectancy’ is so widely used that we all like to think we know what it means, but there is scope for serious misunderstandings.
To calculate the ‘life expectancy’ for someone at a given age is in principle quite simple. Take a large hypothetical cohort of people of that age, and use the mortality rate for that age to estimate the number who will die in the next year. Then take the hypothetical survivors and repeat the process, using the mortality rate for people a year older than the starting age. Continue with the process until all of the hypothetical cohort are ‘dead’. Then add up the total years of survival for the entire cohort, and divide by the number of individuals at the start. This gives average life expectancy at the starting age.
It is easy to see that this single figure for life expectancy tells you very little. There can be enormous variation around the average. It should also be clear that the average (mean) is likely to be different from the median, especially for older age groups. The average is stretched out by the minority of people who live to a very old age. In calculating life expectancy at age 80, one person who lives to 100 has as much weight as 20 people who die at age 81.
Still, life expectancy can be a useful way of summarising and comparing mortality experience of different ages, times, or places. For example, here are life expectancies in 1900 and 2000 for white US males of various ages (expected age at death is in brackets).
This shows clearly how life expectancy at all ages has improved between 1900 and 2000. But it would be a mistake to infer from these figures that a group of people born in 1900 actually lived, on average, for 48 years. The standard calculation of life expectancy uses a ‘period life table’ based on age-specific mortality rates in the same short period of time. So ‘life expectancy’ at birth in 1900 uses the mortality rates prevailing in 1900 for 10-year-olds, 20-year-olds, etc. It is a highly artificial construct.
There is an alternative method, using ‘cohort life tables’, which traces the experience of a cohort of people retrospectively, using the mortality rates which prevailed at relevant periods during their life. So the rate applied at age 30 to someone born in 1900 would be the observed mortality rate for 30-year-olds in 1930, not in 1900, as in the standard method. ‘Life expectancy’ calculated in this way can be substantially different, because it takes account of changes in medicine, nutrition, etc., during the cohort’s lifetime. For example, the cohort method adds more than 5 years to life expectancy at birth in 1900. Unfortunately, it is not always stated which method has been used.
The most prevalent misunderstanding of ‘life expectancy’ is to take it as a reliable prediction of how long people will live in future. The very term ‘life expectancy’ encourages this interpretation. But this is unjustified unless we have good reasons for supposing that age-specific death rates will stay the same as they are now. Over the short-to-medium term this is reasonable, in modern Western societies, because death rates usually do not change very rapidly. But over the long term they do change substantially. So if someone says that a newborn baby can ‘expect’ to live (say) 75 years, without heavily qualifying that statement, he is just a snake-oil salesman.
We tend to assume that life expectancy will go on rising, thanks to medical progress, improved nutrition, less smoking, and so on. This is a plausible assumption, but it could turn out wrong. Apart from the possibility of unknown new viral diseases, antibiotic-resistant bacteria, etc., there is the possibility that the genetic quality of the population is deteriorating. Calculations of life expectancy tacitly assume that today’s newborn children will be as resistant to disease in 80 years’ time (if they live that long) as present-day 80-year-olds are. But present-day 80-year-olds were born in the 1920s, when there were no antibiotics, nutrition was poor, TB was rampant, and infant and child mortality were much higher than now. To have survived to their 80s, they must be tough cookies. There is no guarantee that today’s children (or ourselves) will be equally resistant.