"I had so much it didn't seem fair": Eight-year-olds reject two forms of inequity.

Research using economic games has demonstrated that adults are willing to sacrifice rewards in order to prevent inequity both when they receive less than a social partner (disadvantageous inequity) and when they receive more (advantageous inequity). We investigated the development of both forms of inequity aversion in 4- to 8-year-olds using a novel economic game in which children could accept or reject unequal allocations of candy with an unfamiliar peer. The results showed that 4- to 7-year-olds rejected disadvantageous offers, but accepted advantageous offers. By contrast, 8-year-olds rejected both forms of inequity. These results suggest that two distinct mechanisms underlie the development of the two forms of inequity aversion.