Where is this shown ? In the Oxford data you link in the sibling comment, in the "Student numbers" PDF, the 2015 ratio for male/female Postgraduate research is

Where is this shown ? In the Oxford data you link in the sibling comment, in the "Student numbers" PDF, the 2015 ratio for male/female Postgraduate research is 1.37, Postgraduate Taught is 1.18 and for Undergraduate 1.12, in agreement with the 'especially' in the article.