I recommend reading Coming Apart by Charles Murray, where assortative mating is discussed extensively. There are also some interesting articles you might want

I recommend reading Coming Apart by Charles Murray, where assortative mating is discussed extensively. There are also some interesting articles you might want to read: http://www.nytimes.com/2015/12/27/upshot/marriages-of-power-couples-reinforce-income-inequality.html?hpw&rref=upshot&action=click&pgtype=Homepage&module=well-region&region=bottom-well&WT.nav=bottom-well&_r=1 http://www.nytimes.com/2015/12/27/upshot/marriages-of-power-... http://www.nytimes.com/2016/02/23/upshot/rise-in-marriages-of-equals-and-in-division-by-class.html?_r=0 http://www.nytimes.com/2016/02/23/upshot/rise-in-marriages-o... http://www.economist.com/news/united-states/21595972-how-sexual-equality-increases-gap-between-rich-and-poor-households-sex-brains-and http://www.economist.com/news/united-states/21595972-how-sex...