Raven (Jr) controls the use of his late father's Raven's Matrices and there has not been a proper published adult standardisation for ages. If you look at the current tables the whole thing is incredibly crude. A single extra point changes the percentile ranks considerably. Recently there was a substantial standardisation of the children's version, but until we get proper standardisation data on adults all analyses will have to be done on the raw figures alone. This is not a satisfactory situation, and reduces the applicability of what is essentially a good test.

A minor point on Raven's Matrices, which Jensen has always considered a good measure of g: the easy items are almost a definition of what it is to be intelligent, in that if you can't work them out then you have a very severe problem. I am sure Jane Austen would have coped. The point is that, for a well known test, the standardisation data is extremely crude, and the percentile ranks derived from the test are a crude mess. The raw scores are fine, and most studies concentrate on them, but the adult form needs a good re-standardisation before we can use the test to answer the important question of how much total intelligence is raised by adoption.

On the issue of the different achievements of Indians and Pakistanis in the UK, I think that immigration histories may have something to do with it. I understand that the original immigrants from Pakistan to Uk had been moved from their rural locations because of a dam project which flooded their farms. This would suggest lower intelligence following the usual rural/urban difference. Many Indians came to the UK as part of a betterment project: the opportunities were better, so long as the immigrants were carefully selected by their families as having the abilities and character necessary to put up with the stresses of migration. This would suggest more upwardly mobile and probably urban people, likely to be of higher intelligence. Migrations often attract very different sections of the bell curve, and this could be a partial explanation of the figures for recent African migrants, as upwardly mobile citizen who feel that Europe offers far better prospects than Africa at the moment. Frankly, although these data sets are interesting, I don't think we can make too many genetic assumptions when there are so may cultural biasing factors which relate to immigration histories.

At the formative stages of Sure Start I wrote to the Dept of Education asking if they had anyone on their planning team to run through the academic literature on compensatory education. The rather confused reply was that they hadn't included academics, but anyone could write in with suggestions! I was astounded at the lack of intellectual input, ignorance of the evidence based literature, and general unwillingness to learn from the past. I think I wrote them a few notes about the Abecedarian project, making the observation that apparent early gains in the 0 to 5 years of life rapidly faded, but still left a useful residue of 4 IQ points in later life. As you say, if there are no effects now, there will very probably be none later at any stage.

If education raises iq then it would be a commonplace that compensatory educational programs would create permanently raised iqs. Headstart failed, the Abecedarian project delivered 4 iq points, useful but hardly dramatic given the heroic input required (individual tutors from 4 months of age, dedicated high quality teaching till 5 years). Longitudinal studies can look at cross lagged correlations: ie. given iq and scholastic scores at 11, which are the better predictors of scholastic scores at 18.

Once again Ian Deary has got excellent population data and combined it with other data sets to produce clear results. His work is really taking on the concept of intelligence in terms of real life utility, and when his health and longevity studies are eventually completed we shall have a strong case for g being a fitness indicator of the highest order.

http://thompsonja.blogspot.com/ 
 
A single post about iq and social mobility in Britain, triggered by a report into increasing access to university.

Razib - I now see that you appear to propose two main measures of the benefits of immigration to the host country: the purely economic and the "ethno-cultural". A stranger may contribute to the former but detract from the latter. The clever Jew of your example boosts wealth but diminishes the "we are all Catholics together" feeling of the Catholic majority. This would be an entho-cultural loss. For example, London is full of strangers, and it is very difficult to share a joke, because of linguistic and cultural barriers. Therefore, the sense of being a Londoner, and having shared social capital, is dimished, even destroyed. People may retreat to same race, same class enclaves, and see the city as alien space. However, as others have observed, the only answer would be to require public mono-culturism as a condition of citizenship.

Razib, your reference to V-Dare has somewhat lost me. My premise is that immigration is primarily based on economic advantage: people emigrate to advantage themselves, and other countries let them in because they in turn seek some advantage. Low skill immigrants make immediate gains in wages, help take over unpleasant jobs, but vary in their ability to rise up the value chain. High skill immigrants contribute far more value, and as such benefit the host country considerably. Yes, all immigration imposes a "translation" cost, because different cultures have to put energy into understanding each other, and multi-culture can be a dangerous brew, though the US has done better than most at making it work. In the UK I think that immigration was unselective, short term, and based on a naive belief that all immigrants would "aculturate" by exposure to the weather. There was no nationalistic policy of integration, and until very recently, no ceremony surrounding "being British". (The concept still causes embarassment). But yes, the Japanese can say that being Japanese is best, and that stagflation at a very high standard of living is an entirely acceptable policy, with a settled and peaceable society.