This tab examined the issue of 'gender shaping' last year and we continue the discussion here. This time we analyze simple probability models related to this issue. Imagine a population in a geographical area where parents adopt a policy of 'stop having children after the first boy'. Surprisingly (or maybe not), this practice in itself cannot really 'shape' or affect the stability of the population, as neatly explained by Prof. Thomas C. Schelling in his book 'Micromotives and Macrobehavior': no “stopping rules,” like stopping after the first boy, can affect the ultimate proportions. At the first round, half the babies will be boys. At the second round, only half the families have children, but they will be half boys. The half with only girls will proceed to the third round and again, by the 50–50 hypothesis, half will have boys and half girls. If at each round half are boys and half girls the total—no matter where it stops—will be half boys and half girls. (A corollary is that we know, without adding, how many children will be born. In the end, every family will have one boy; girls will equal boys; and, the average will be two children per family.)
Dr. Schelling also mentions: "It has occasionally been proposed that this motivation might explain a slight excess of boys over girls in some populations. Where female infanticide is practiced it is bound to have that result."
Thus when one sees F-M ratios like 89:100 in some pockets of Northern India, it's a scary indicator that a sizable percentage of baby girls have been murdered (the Gov of India has had in place a strict ban on sex-determination tests for many years now). Female infanticide is a relatively recent phenomenon in certain sections of society within India's 7000+ year culture where women were typically accorded an equal (perhaps higher) status compared to men. Russel Ackoff has discussed a related issue in his classic book many decades ago.
Although the boy-driven stopping rule does not affect the stability of the population and the resultant average family looks pretty normal, the internal distribution is asymmetric (another example of the flaw of averages?). For example, a boy will either be the only kid or the youngest kid in the family. In the latter case, the parents are 'focused' on producing a boy and then tending to his needs and thus more likely to ignore the needs of their girl babies, and as the family gets bigger, this situation, on a per-capita basis is likely to get worse. These conclusions are largely confirmed in a recent NBER econometric/statistical study that uses data-driven analytical models to answer the question "Are boys and girls treated differently". Girls brought up to adulthood in such a biased environment may well help perpetuate this vicious cycle in certain parts of India. The U.S. does not appear to suffer from the problem of gender-shaping, although the pro-abortion groups have required some deft arguments to enunciate their stance on the selective gender-based abortion question posed by anti-abortionists. On the other hand, there may be some issues to be overcome with respect to investments in girl children as far as their career choices, as very briefly touched upon in a prior post.