"If negative stereotypes are present regarding a specific group, group members are likely to become anxious about their performance, which may hinder their ability to perform at their maximum level. For example, stereotype threat can lower the intellectual performance of African-Americans taking the SAT reasoning test used for college entrance in the United States, due to the stereotype that African-Americans are less intelligent than other groups. Importantly, the individual does not need to subscribe to the stereotype for it to be activated. Moreover, the specific mechanism through which anxiety (induced by the activation of the stereotype) decreases performance is by depleting working memory (especially the phonological aspects of the working memory system).
But do note that the same wikipedia page points out that several recent attempts to replicate the studies that claimed to measure stereotype threat have failed, putting the whole idea into question.
I'm not saying that out of some attempt to sweep away the general problem of improving diversity; it's just important to work on solutions that will actually make a difference.
There are also recent studies that confirm different manifestations of it, for example [1]. I tend to agree with Wikipedia on the publication bias aspect, but I don't think you can sweep away the impact of stereotypes at all. I also think working to change tech stereotyping (in general) as one of the things that will actually make a difference, so I guess I'm biased too.
> For those wondering why this is important, see:
http://en.wikipedia.org/wiki/Stereotype_threat
"If negative stereotypes are present regarding a specific group, group members are likely to become anxious about their performance, which may hinder their ability to perform at their maximum level. For example, stereotype threat can lower the intellectual performance of African-Americans taking the SAT reasoning test used for college entrance in the United States, due to the stereotype that African-Americans are less intelligent than other groups. Importantly, the individual does not need to subscribe to the stereotype for it to be activated. Moreover, the specific mechanism through which anxiety (induced by the activation of the stereotype) decreases performance is by depleting working memory (especially the phonological aspects of the working memory system).
[1] https://news.ycombinator.com/item?id=6966969