What is going on is simple, and obvious to anyone with eyes - and I saw it happening in my kids primary school in a North Eastern city in England during that period of massive immigration through the 2000s.
The ability of the native population was on a bell curve, and the ability of immigrants was bimodal.
The Chinese (including Korean, Taiwanese, Hong Kong etc) were all in the top maths group and the top maths groups was mostly Chinese, one Jewish boy and a couple of locals. The bottom Maths group was I recall entirely Pakistani, Bangladeshi, Arabic, and African. Indeed the best students in most classes were usually Chinese - even though there were local kids of middle class professional parents in a higher proportion than usual.
When we got the children's attainment test scores, we were given the scores for the whole class (anonymously) to give context, and I was astonished to see they were actually bimodal (for 90 children - not symmetrical - since there were a lot of highly able children, but with two peaks and a point of rarity between). I asked the teacher why - given that this is a very unusual distribution for a school, but she had no idea, and it seemed that nobody had noticed or commented on the fact. The proportion of immigrant children was so high that it made this bimodal distribution.
The deep problem is that concepts such as 'immigration', and even more 'diversity', are actually calculated to conceal and confuse, by lumping together heterogeneous and indeed contrasting entities.
When we are forced to debate using these categories things seem much more complicated than they really are - thereby people cannot follow, and lose interest in the 'debate' - which is exactly the intention.
Hi James,
ReplyDeleteI read your recent immigrant paper. Apart from a few minor quibbles (e.g., calculating within country standardized differences using the cross national (?) SD of 100), I felt that it was excellently executed. Unfortunately, you didn't look at scores by country of origin.
While you did find that migrant scores highly correlated with those of natives, something which I didn't find when restricting consideration to European nations, as you noted, there are proximity migration effects which manifest when looking at a wider range of countries i.e., poorer scoring Latin Americans migrating to poorer scoring Latin American countries. Thus there seems to be an important confound. A paper now long in development by De Philippis, "Parents’ Country of Origin and Intergenerational Mobility of School Performance", did find that nation of origin is a substantial predictor of second generation PISA performance, taking into account national level effects, which include e.g., the effect of migrating to geographically, and thus cognitively, proximate nations. Unfortunately -- I seem to never be able to get exactly what I'm after -- the author didn't present effects controlling for parental selectivity (the difference between migrant parental attributes and the average of the origin nation ones), despite investigating the topic somewhat. Rather, effects controlling for SES differences between natives and immigrant parents are presented -- for my interest, this is controlling for the wrong differences. Anyways, to get to the point I was wondering if you were planning to extend the analysis by looking at origin effects (for PISA of course, which has the data)?
Dear John, Thank you for your detailed comments. I will answer the easier questions first, and then prevaricate on all the others, for a while anyway. Rindermann has a long list of papers in the pipeline, and we keep trying to bring them to publication, particularly because I have got so used to many of them in draft form that I keep imagining they are published, and very much want to reference to them. Getting further into origin effects is desirable, and we are aware that "who goes where and why" in terms of immigrant flows across the world is a likely confound, as you say. Personally, I am surprised how well the predictions come out if you assume that an immigrant from a particular country is probably at the average for that country, and will remain close to that for quite a while.
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