Genes and backgrounds matter most to exam results
Mar 26th 2018
PARENTS in England are faced with a choice when their children are old enough to attend secondary school. They can pay to send their offspring to a private school, which usually involves sitting an entrance exam. Alternatively, in some parts of the country, the child can sit an eleven-plus exam and, provided they pass, attend a grammar school. Grammar schools are publicly funded and tend to excel in league tables of academic performance. The overwhelming majority (about 90%) of British pupils, however, attend non-selective state schools.
英国的父母在他们的孩子长到可以上中学的时候，面临着一个选择。他们可以花钱把他们的孩子送到私立学校，这通常包括参加入学考试。或者，在这个国家的一些地方，孩子可以参加11 plus考试，只要他们通过，就可以上一所文法学校。文法学校是公共资助的，并且在学术表现的排行榜上比较出类拔萃。然而，绝大多数（约90%）的英国学生就读于非精英的公立学校。
Debate has raged for years over whether most selective schools do well because they provide a better education than state schools, or merely because they cream off the brightest and most privileged. According to research led by Robert Plomin and Emily Smith-Woolley, both of King’s College London, the educational benefits of selective schools largely disappear once the innate ability and socio-economic background of pupils at selective schools are taken into account.
多年来，人们一直在争论，大多数精英学校是否真的表现良好，因为它们提供的教育比公立学校更好，或者仅仅是因为它们攫取了最聪明、最富有的学生。根据伦敦国王学院的Robert Plomin和Emily smith woolley领导的研究，一旦考虑到精英学校学生的先天能力和社会经济背景，精英学校的教育优势就会消失。
As they report in npj Science of Learning, the researchers selected over 4,000 unrelated individuals from the Twins Early Development Study, a large ongoing project gathering information from British twins born in the mid-1990s. That information includes DNA data and the results of intelligence tests and exams.
正如他们在npj Science of Learning中所报道的，研究人员从双胞胎早期发展研究中挑选了4000多名不相关的个人，这是一个正在进行的大型项目，收集来自上世纪90年代中期出生的英国双胞胎的信息。这些信息包括DNA数据和智力测试和考试的结果。
At first the researchers calculated a genetic score taken for each child by adding up contributions from thousands of minor variations in their DNA that past studies (including data from 300,000 individuals) have linked to educational attainment. Pupils attending grammar and private schools had significantly higher genetic scores than those in comprehensives. But when those scores were adjusted to reflect each child’s test results at 11, as well as the education and occupations of their parents, the differences vanished. That makes sense. Previous research has shown that many of the traits that selective schools are screening for are, in part, inherited from their parents. The tests being used by schools appear to be inadvertently picking up some of these genetic differences.
起初，研究人员计算了每个孩子的遗传分数，通过加总他们的DNA中成千上万个微小的变化的贡献因素，过去的研究（包括30万人的数据）与教育程度联系在一起。在文法学校和私立学校就读的学生的遗传分数明显高于综合学校的学生。但是，当这些分数被调整，以反映每个孩子在11岁时的考试成绩，以及他们父母的教育和职业时，这些差异就消失了。这很有意义，之前的研究已经表明，精英学校所筛选的许多特征，在某种程度上是遗传自父母的。学校使用的测试似乎无意中发现了其中的一些基因差异。
The researchers then scored each child based on the results of science, maths and English GCSE exams, typically taken by all schoolchildren in England and Wales at the age of 16. On average, the results of children at private or grammar schools were a full GCSE grade higher than those at state schools. That suggests attending a selective school gives children a boost. Without correcting for any other factors the researchers calculated the boost to be worth about 7.1% of the difference in GCSE results.
然后，研究人员根据科学、数学和英语GCSE考试的结果对每个孩子打分，这通常是英格兰和威尔士所有学生在16岁时要参加的考试。平均而言，私立或文法学校的孩子的成绩比公立学校的学生要高。这表明，参加一所精英学校会推动孩子。在没有纠正其他因素的情况下，研究人员计算出了在GCSE成绩中，这种推动力在上述差异中，所占比例为7.1%。
But was this due to better teaching at these schools or an outcome of the selection procedure? To see, the team adjusted the grades based on the results of each child’s test scores, family circumstances and genes. Once they did this, the gap between the schools narrowed dramatically, with school type explaining just 0.5% of the difference in average GCSE grades. For any individual, genetics accounted for about 8% of the difference, modest in comparison with the many other factors involved, such as socio-economic backgrounds, test results at 11 and things still to be accounted for.
但这是由于在这些学校更好的教学还是选择流程的结果？为了观察，研究小组根据每个孩子的测试成绩、家庭环境和基因的结果调整了分数。一旦他们这样做了，学校之间的差距就缩小了，学校类型只解释了平均GCSE成绩差异的0.5%。对于任何一个人来说，遗传因素占了其中的8%，与其他许多因素相比，这是中等的，比如社会经济背景，11岁的测试结果，还有一些有待解释的因素。
The research comes with important caveats. First, the thousands of genetic variations so far linked to educational attainment are not well understood. Many of these variations may not be linked to intelligence at all. If, for instance, a weak bladder leads a child to perform poorly in timed exams or protuberant ears means bullying blighted their education, genetic variants for these traits will show up as disadvantageous. Stronger bladders and flatter ears will therefore confer advantages and better genetic scores. Second, had the study also been conducted in a nation, such as Denmark, where wealth is more evenly spread it is possible that genetics would appear to play a bigger role in educational outcomes, because socioeconomic disparities would have a lesser impact.
这项研究提出了一些重要的警示。首先，迄今为止，与受教育程度相关的数千种基因变异还没有得到很好的理解。这些变化中的许多可能根本与智力无关。例如，如果一个虚弱的膀胱导致孩子在计时的考试中表现不佳，或者是突出的耳朵，就意味着恃强凌弱会破坏他们的教育，那么这些特征的遗传变异就会被认为是不利的。因此，更强的膀胱和更平的耳朵将会带来优势和更好的遗传分数。其次，如果这项研究在一个国家进行，比如丹麦，那里的财富分布更加均匀，那么基因在教育结果中似乎扮演着更重要的角色，因为社会经济差异的影响较小。
The research does not appear to support “progressive eugenics”, as advanced by Toby Young, a journalist and a co-author of the study. Mr Young has argued that poor people should be able to screen embryos free on the basis of intelligence, if the technology becomes available. Setting aside ethical questions, many of the genetic differences that might appear to contribute to social mobility (think flatter ears, etc) may not be associated with actual intelligence. Overall, such an idea might shift educational attainment by a few percentage points at best. That is tiny compared with the advantages enjoyed by the children of the educated and wealthy.
这项研究似乎并不支持“进步的优生学”，这是由记者托比杨提出的，他也是这项研究的合作者之一。杨先生认为，如果技术可行的话，穷人应该能够在智力的基础上自由地筛选胚胎。撇开伦理问题不谈，许多可能看起来对社会流动性有贡献的基因差异（比如更平的耳朵等）可能与实际的智力无关。总的来说，这样的想法可能会把教育程度提高几个百分点。与受过教育和富有的孩子们所享有的优势相比，这是微不足道的。
This article appeared in the Science and technology section of the print edition under the headline "Selective evidence"
英文原文选自《经济学人》