Chernyak_SupplementalMaterial_rev – Supplemental material for Paying Back People Who Harmed Us but Not People Who Helped Us: Direct Negative Reciprocity Precedes Direct Positive Reciprocity in Early Development

Supplemental material, Chernyak_SupplementalMaterial_rev for Paying Back People Who Harmed Us but Not People Who Helped Us: Direct Negative Reciprocity Precedes Direct Positive Reciprocity in Early Development by Nadia Chernyak, Kristin L. Leimgruber, Yarrow C. Dunham, Jingshi Hu and Peter R. Blake in Psychological Science