Here's the new thread for posting quotes, with the usual rules:
- Please post all quotes separately, so that they can be voted up/down separately. (If they are strongly related, reply to your own comments. If strongly ordered, then go ahead and post them together.)
- Do not quote yourself
- Do not quote comments/posts on LW/OB
- No more than 5 quotes per person per monthly thread, please.
What determines it? Ancestry. Race is basically a way of asking "who were your ancestors?" and accepting a blurry answer because, well, each person has a lot of ancestors! That version of race is obviously a biological reality, because people have different ancestries, even going back long distances, and the ancestry distribution can be geographically plotted. If you go back thirty generations for me, I would need to have about a billion distinct ancestors for there to be no inbreeding; the entire world didn't have that many people! Europe, the probable source for most of my ancestry, only had about 50 million people thirty generations ago, and even then it's unlikely that all of them are my ancestors- for one, many of them didn't have any children! I'd estimate somewhere less than 10% of the total world population at any point since 1000 AD is in my ancestry, and the distribution of their contribution to my ancestry is pretty localized. It's probable there's many people out there who share none of my ancestry for a full thirty generations back, and there's one who (probably) shares it completely.
Knowing she was adopted from Africa, odds are good that she's mostly African. That's only one step more informative than "human," since it only gives you the archaic racial category- Negroid- which tells you as much as "Caucasoid" or "Mongoloid." Ethnicity would give a much narrower picture- about one person in six is African, but only about one person in four thousand is Gurage.
Adding on the data that she's Ethiopian muddies the picture- due to its northeastern position, Ethiopia has been the site of significant mixing, and there's quite a bit of ethnic diversity: the primary ethnicity, Oromo, is only a third of the population- your Chinese daughter, though, most likely has significant Han ancestry (92% of the population of mainland China).
So, using the archaic terms and assuming she's from one of the more prevalent ethnicities, your daughter probably has about 60% Caucasoid ancestry and 40% Negroid ancestry.
So, good IQ estimates in Africa are generally hard to come by, but Ethiopia supposedly has the world's lowest average IQ, at 63 (administered in 1991, sample size of 250), and China is estimated to have an average IQ of 100. Working off that data (and assuming both groups have a standard deviation of 15), that gives a 96% chance that the Chinese daughter is smarter. Now, the Ethiopian data is spotty, especially the normality assumption- one of the pitfalls of historic IQ testing is that 0 scores are treated as 0s, dragging down the average, instead of an separate number of "people who didn't understand the concept of the test." It's also not clear what selection effects adoption has; children that get adopted out are likely to not be representative of the country as a whole, and it's hard to say if that would be a positive or negative effect. If we use the African American average IQ of 85 instead of the estimated Ethiopian averaged IQ, and still assume that we should use the Chinese average, we get a 76% chance that the Chinese daughter is cleverer.
Of course, given that they're your daughters, there's not much reason to guess; you could just get them both tested, which would be way cheaper and more informative than sponsoring another test of Ethiopian national IQ.
Yep. The most recent common ancestor of living humans lived at least a couple millennia (i.e. about seventy generations) ago. (EDIT: I'm not fully convinced that that implies that for any time t later than that, there's at least one with you no ancestry at time t. I'm too tired to trust my cognitive abilities right now.)
Do you have any reason in particular to suspect that you and your sibli... (read more)