Assortative mating and income inequality

Jeremy Greenwood, Nezih Guner, Georgi Kocharkov and Cezar Santos have a new NBER Working Paper, the abstract is this:

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.

That is quite a significant effect.  There are ungated versions of the paper here.  Here is a related post by Alex.

Addendum: Kevin Drum offers additional comment.