A gender pay gap is generally calculated by finding the mean pay for women and the mean pay for men and calculating
( (mean pay for men)/(mean pay for women) – 1 )
( 1 – (mean pay for women)/(mean pay for men) )
assuming that the mean pay for women is lower. The former is larger and consequently sounds more impressive: the latter is the definition used by the Office of National Statistics in the UK (http://www.statistics.gov.uk/cci/nugget.asp?id=167). Sometimes the median is used rather than the mean. The median tends to be more typical since it is the point where half the population earn more and half less. Mean pay can be sensitive to a few individuals who earn much more than everybody else.
Mathematically, both the median and the mean depend on the relative frequency, which is the proportion of the population earning a particular salary. If analysis shows that women and men are paid the same for the same or equivalent jobs, then the gender pay gap is determined by the difference in the way men and women are distributed across grades. A gender pay gap results if women are more likely than men to be in lower paid positions and less likely than men to be in higher paid positions. The gender pay gap is independent of the overall proportion of women in the institution. An institution with a small overall proportion of women who are fairly evenly distributed between grades would have a small gender pay gap, for example, if every grade had exactly 10% women the gender pay gap would be zero.
The main contributing factors to the gender pay gaps in universities are
- The large proportion of women among clerical and secretarial staff, who tend to be lower paid.
- The small proportion of women among senior academic staff, for example, HESA figures show that in 2007-08, 19% of professors were women while 48% of lecturers were women (http://www.hesa.ac.uk/index.php?option=com_content&task=view&id=1397&Itemid=161).
- Increasing the percentage of women holding professorships, which should be good for women in SET.
- Decreasing the percentage of women among clerical and secretarial staff, which would be irrelevant to women in SET. Unfortunately technicians have similar pay rates so we would also want to decrease the percentage of women among technical staff, which would be bad for women in SET.
- Decreasing the percentage of women among research assistants and post-docs or decrease the total number of post-docs, which might be a good thing for women in SET or might not.
It may also be that not all women want to progress through grades at the same rate as men. Some may prefer to postpone applying for promotion to more responsible and stressful jobs until their children are older. Too much focus on gender pay gaps could make life harder for women who are trying to balance career and family.
A further problem with any measure that reflects occupational and vertical segregation is that it is bound to change only slowly. This is partly because you can’t fire incumbent staff to make way for new staff of the other gender and partly because aspects of the distribution of women, for example, their concentration in clerical and secretarial grades, are the results of societal and cultural factors outside the control of the institution.
We do need some measure of how women are distributed within institutions. Claiming that nearly 50% of your work force are women does not mean much if they are predominantly in low paid and/or insecure positions. Perhaps rather than rely on a single ‘figure of merit’ (or demerit) such as the gender pay gap it would be better to focus on particular areas of concern. For example, if it is felt that the proportion of women among professors is an issue then measure the proportion of women among professors. Similarly, if the career progression of post-docs is an issue then monitor the destinations