Over the years, I’ve noticed that a much higher fraction of my female friends complain about the lack of eligible men, than the fraction of my male friends who complain about the lack of eligible women.* But I’ve always assumed that this couldn’t really be true – that the sex ratio everywhere must be about 50/50.
Now a new paper by Lena Edlund, at Columbia University, suggests that maybe I should’ve paid more attention. But I’m not sure that my female friends would’ve liked Edlund’s explanation:
Throughout the Western world, rural areas are short of young women. Urban areas are not only home to relatively more females, they also offer better labor markets for skilled workers. However, since women are on average less skilled than men, job location alone cannot account for the surplus of women. This paper argues that a combination of marriage and labor market factors may explain the observed pattern.
It is well established that, in partner choice, men value traits that are associated with female fecundity, such as youth. Female fecundity is not only attractive but also scarce. Hence young women tend to have a choice of partners. If women value financial security when evaluating a partner, richer men would face better partner availability. These observations suggest that young women would match with rich men. If such men are in urban areas, this could account for the surplus of women.
If the marriage market is asymmetricâ€”so that for men, marriage follows from good job-market opportunities, but for women, marriage and wage work constitute two alternative sources of incomeâ€”high paying jobs in a locality may imply that it can support more women than men, since women draw income from both jobs and men.
[Edlund goes on to find support for the hypothesis across Swedish municipalities.]
Do Australian data support this hypothesis? I took a squiz at the microdata from the 2001 Census, and found that nationally, the 25-34 age group are 50.7% female. In three cities – Canberra, Perth and Sydney, the fraction of women is above average (supporting the theory). But in Adelaide and Melbourne, the fraction of women is below average (Brisbane has precisely the national sex ratio).
An alternative approach is to regard Australians as essentially immobile within their region of birth, and look at where in the cities they live. Taking this approach, women do seem to be overrepresented in the centres of Australian cities.
* Of course, not everyone is hetrosexual. In 2003, Bob Birrell and coauthors looked at which cities Australian gay couples tend to live in.