One fairly widely reported influence is that women are less likely to request raises (or promotions) and less likely to negotiate salaries on an initial job off

One fairly widely reported influence is that women are less likely to request raises (or promotions) and less likely to negotiate salaries on an initial job offer. One hypothesis for why this is so is that women who ask for things are seen as pushy/demanding whereas men who ask for things are seen as go-getters, not sure what the research on that is like at the moment. However I also remember reading a study that showed people reading a resume with a female name proposed a lower salary offer in the first place (academics in math, I believe). So, all of the above?