If more YC partners were female, it could result in more women applicants because it might provide encouragement to potential female startup founders who are on the fence that successful entrepreneurship in a male-dominated startup environment is achievable--and ultimately worth striving for. Social science studies point to a gap between similarly-qualified men and women on their respective levels of self-confidence and risk tolerance. The implication of this gap is that while the gender makeup of YC partners wouldn't affect the decision of most men to apply, the presence of women could have the effect of encouraging women to apply by demonstrating what can be achieved.

Ultimately, this is a pipeline issue--there are just not enough women founders who go on to be angels and VCs.