New research says selective schools "make almost no difference"

Oops, sorry, just noticed the OP posted the source already!

It's worth nothing that there are a number of limitations to the study, some of which are acknowledged in the paper itself.

Firstly, the study only measures the results of science, maths and English GCSEs. Those are the subjects that are most likely to be set in state schools, because they have the largest numbers of pupils, and because maths in particular is perceived as a hierarchical subject. So the potential influence of a lesser degree of setting in subjects like MFL or history in state schools won't appear in the analysis.

The authors also dont acknowledge the potential ceiling effect that arises from using GCSEs as a measure, and especially those particular GCSEs. (One of the really odd omissions here is that they refer to an "English" GCSE, but don't seem to specify which one - even though they explain about triple science, and that they used an average of the 3 scores for that.) Especially if it is English Language they chose to use, the ceiling effect in that particular exam would have a big impact.

By "ceiling effect" I mean that GCSEs don't measure broader learning "above and beyond" what is required to get an A* at GCSE: learning that will be especially useful for A levels and university, as well as worthwhile in itself . This type of learning is much more significant for those whose A levels and degrees will be in humanities subjects, IMO , which is why I am concerned about the narrow range of GCSEs covered in the study.

Still, it's an interesting paper, even though I don't think it can be regarded as definitive. I'd be interested in the views of scientists/ mathematicians/psychologists on the methods of analysis and the reliability of the adjustments they made to the raw data.

You can read the whole thing here: www.nature.com/articles/s41539-018-0019-8

Hmmmmm. I think this study swerves to map the relationship of specific genes with school achievement.
I don't think it challenge previous findings that approx. 50% of variance in achievement/ability (depending on what you think the tests actually measure) can be accounted for by genes/heredity factors and approx. 50% by environmental factors.
We know that the environment interacts with genes and so even genetic influences will be influenced by the environment - diet, toxins, stress etc. will all interfere with our genes.

Isn’t the assumption that you can map intelligence/ educational potential to genes rather a contested one though?

If would of been interesting if they had selected another group from a non grammar area who attend comprehensives who had similar genetic profile to grammar to see how they performed in their GCSE's, if the study was to show the value of grammar/selective schools.

I'm not surprised by this at all.

Something that doesn't seem to be getting much press (the Guardian article doesn't even mention it!) is that all the students in this study were twins. My impression from private schools is that twins are really unusual - partly for obvious financial reasons. I have less evidence for it, but I think twins may also be less likely than singletons to be put in for selective grammars, because of the "what if only one gets in?" factor. So I wonder whether the results would be the same or different for non-twins?

Mostly this seems rather unsurprising. GCSEs are so basic that I would expect their ceiling effect to make using GCSE grades as a proxy for achievement really problematic. It may be the first time since The Bell Curve that it's been allowed to say that genetics might actually matter to achievement, though!

While I like the findings of the research I’m a bit uncomfortable about Toby Young’s involvement in a study involving research into genetics and intelligence.

Totally agree. It is not the school or teacher that matters but the student.