Assortative marriage for specific cognitive abilities in two ethnic groups.
D000223:Adaptation, Psychological; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D003071:Cognition; D005006:Ethnicity; D005060:Europe / Q000208:ethnology; D006801:Humans; D007564:Japan / Q000208:ethnology; D008393:Marriage; D008875:Middle Aged; D012737:Sex Factors; D014481:United States