It examined a wide set of results, including verbal reasoning tests, done by 11-year-olds enrolled in two major studies.
For both sets of children, the parents' socio-economic background was the most significant factor.
For those born in 1970, according to the authors, it didn't really matter where in England they were born and grew up - but for those born in 2000, regional difference had become "a more powerful predictive factor".
In 1970, being from an ethnic minority was a disadvantage: today the picture is more mixed, with some minority groups, like Chinese or Indian children, doing better than average.
Ofsted has warned of the regional variation for several years: in 2013 chief inspector Sir Michael Wilshaw described it as "unacceptable".
There is considerable difference between regions at GCSE. Last year, 72% of pupils in London achieved grades of A* to C, compared to 65% in Yorkshire and Humberside.
