From the article- 
When a group of computer science students decided to study the way that gender bias plays out in software development communities, they assumed that coders would be prejudiced against code written by women.<p>After all, women make up a very small percentage of software developers – 11.2% according to one 2013 survey – and the presence of sexism in all corners of the overwhelmingly male tech industry has been well documented.<p>So the student researchers were surprised when their hypothesis proved false – code written by women was in fact more likely to be approved by their peers than code written by men. But that wasn’t the end of the story: this only proved true as long as their peers didn’t realise the code had been written by a woman.<p>“Our results suggest that although women on GitHub may be more competent overall, bias against them exists nonetheless,” the study’s authors write.