, they were asked to fill out an informed consent form. A total of 80 children in the preschool
were recruited. At each laboratory visit, 2 children were brought together to take part in a peer dyad assessment. One of the children, chosen randomly, was treated unfairly during the board game,
whereas the other child always won. Then, both children completed the selective attention task separately.
Here, 40 children (24 boys and 16 girls, mean age = 6.10 years, SD = 0.27) who were treated
unfairly during the game served as participants in further analyses. All of the children were from intact,
single-child families; the majority of the parents (95.0%) had a college degree. The sample mainly
represented socioeconomically middle to upper middle class in Hangzhou as reported by monthly
family income (25.0% with ¥10,000; at the time
of the experiment in 2009, average monthly family income in Hangzhou was ¥5000).