1. Women [1]
2. Older Americans [2]
3. Minorities [3]
4. Foreigners [4]
What can be done about this? The answer is clear: anonymous screening, interviewing and hiring of candidates. All other solutions are subpar.
People will argue that there's value to be had in asking about things such as hobbies, and other irrelevant, superfluous information, but those who advocate this are probably not in one of the groups mentioned.
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[1] http://www.vogue.com/article/female-discrimination-tech-indu...
[2] https://www.forbes.com/sites/lizryan/2014/01/31/the-ugly-tru...
[3] http://money.cnn.com/2015/11/25/news/economy/racial-discrimi...
[4] http://www.huffingtonpost.com/alev-dudek/foreign-born-citize...