Gender is a clear indicator for unbalance in any kind of context. Assuming only two genders (OK, a bit antiquate but a good first-order approach), the population can be split in two equal halves. Therefore, any environment in which genders are not represented equally has a bias .
Gender does not identify a minority , talking about women as a minority is a problem. Should be referred to as an under-represented group (See women are half the population, not a minority )
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