A new study into causes of the scarcity of women in technical and scientific fields says that it is not discrimination by men in the field keeping the ladies away. Nor is it a repugnance felt by women for possibly dishevelled or unhygienic male nerds.

No, the reason that young women don't train in Science, Technology, Engineering and Maths (STEM) areas - and thus, don't find themselves with jobs at tech companies, in IT etc - is quite simply that they mostly don't know enough maths to do those courses.

"It is all about the mathematical content of the field. Girls not taking math coursework early on in middle school and high school are set on a different college trajectory than boys,” says economics prof Donna Ginther.

Ginther and a colleague, Shulamit Kahn, examined statistics on young women's maths qualifications and mathematical requirements for college courses in America. Put simply, they found that absence of women studying a given course can be accounted for simply by the fact that most young women don't know much maths.

The two economists were seeking to debunk a much-discussed study earlier this year which suggested that women were being kept out of STEM fields by innate prejudices held by faculty in those areas. The study was conducted by a philosopher, two psychologists and a sociologist.

“Their results didn’t add up,” Ginther says bluntly.

Other theories as to why there aren't many women in tech or (hard) science have been advanced. Some say that putting up sci-fi posters and leaving tins of coke about puts women off; others that women are just simply repelled by nerds; others that the problem - specifically for very attractive women - is that they fail to mention the fact that they're very attractive during job interviews.

Our own Tim Worstall chipped in recently on this subject, suggesting like Ginther that girls perhaps get steered out of maths - and thus out of engineering, tech and the tough sciences - well before any STEM people get a look at them.

"Really it happens a lot earlier than college,” says Ginther.

Ginther and Kahn's technical comment challenging the study appears today in premier boffinry mag Science, which also published the original paper. ®