Assortative Mating

Assortative mating is a nonrandom mating pattern in which individuals with similar genotypes and/or phenotypes mate with one another more frequently than would be expected under a random mating pattern.

Once upon a time, during a brief egalitarian period in postwar America, people of different classes did not live in separate worlds. The promise of mobility and prosperity was alive throughout the land. In 1950, Walt Disney Productions was saved from bankruptcy with its smash hit "Cinderella," which audiences cheered at a time when the future looked bright and it was still possible for the dream of marrying up to come true.

A new Disney film of "Cinderella" is a big box-office success today, but how different things look! Cinderella marriages are getting to be as rare as golden coaches. Economist Jeremy Greenwood has found that your chances of marrying outside your income bracket have been dropping since the 1950s because of something called assortative mating, which means that we are increasingly drawn to people in similar circumstances.

Since the 1980s, inequality has grown and mobility has stalled. Today, the rich forge their unions in exclusive social clubs, Ivy League colleges and gated communities. Unless you have a fortune or a fairy godmother, you're probably out of luck. Without that magic, the gates remain closed.

In the end, Cinderella gets the prince and the palace, and the other women get absolutely nothing. That's the way of tournaments.

http://www.reuters.com/article/2015/03/27/parramore-cinderella-idUSL2N0WT2L120150327

Marry Your Like: Assortative Mating and Income Inequality
Jeremy Greenwood, Nezih Guner, Georgi Kocharkov, Cezar Santos

NBER Working Paper No. 19829
Issued in January 2014
NBER Program(s):   EFG

Has there been an increase in positive assortative mating? Does assortative mating contribute to household income inequality? Data from the United States Census Bureau suggests there has been a rise in assortative mating. Additionally, assortative mating affects household income inequality. In particular, if matching in 2005 between husbands and wives had been random, instead of the pattern observed in the data, then the Gini coefficient would have fallen from the observed 0.43 to 0.34, so that income inequality would be smaller. Thus, assortative mating is important for income inequality. The high level of married female labor-force participation in 2005 is important for this result.