Three experiments examined children's understanding of how supply and demand affect the difficulty of completing goals. Participants were 368 predominantly White Canadians (52% female, 48% male) tested in 2017–2022. In Experiment 1, 3-year-olds recognized that obtaining resources is easier where supply exceeds demand than where demand exceeds supply. However, in Experiment 2, 3-year-olds were insensitive to supply and demand when comparing situations where demand exceeded supply to a greater or lesser degree. Finally, Experiment 3 revealed a developmental lag in 3- to 7-year-olds' understanding of how supply and demand affects goal completion: Children succeeded when contrasting a surplus and a shortage of supply relative to demand at 4;2. But they only succeeded when contrasting degrees of greater supply than demand at 5;10.

中文翻译：

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容易还是困难？儿童对供需如何影响目标完成的理解

三项实验检查了儿童对供需如何影响完成目标的难度的理解。参与者是 2017-2022 年接受测试的 368 名主要是加拿大白人（52% 女性，48% 男性）。在实验 1 中，3 岁的孩子认识到，在供过于求的地方比在供过于求的地方更容易获得资源。然而，在实验 2 中，3 岁儿童在比较需求或多或少超过供应的情况时对供求不敏感。最后，实验 3 揭示了 3 至 7 岁儿童对供需如何影响目标完成的理解存在发展滞后：当将供应过剩和供应短缺与需求进行对比时，儿童成功了 4;2。但他们只有在 5:10 对比供大于求的程度时才成功。