Aggressive and friendly behaviors of young children from two social classes.
D000367:Age Factors; D000374:Aggression; D002652:Child Behavior; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007398:Interpersonal Relations; D008297:Male; D009519:New York City; D010287:Parent-Child Relations; D010379:Peer Group; D012578:Schools, Nursery; D012737:Sex Factors; D012919:Social Behavior; D012923:Social Class; D014705:Verbal Behavior