Williams J D, Brekke B W
J Genet Psychol. 1979 Jun;134(2d Half):179-84. doi: 10.1080/00221325.1979.10534052.
High school students aged 15 through 19 years (N = 116) were administered three Piagetian type tasks (conservation of weight, paper and pencil tests of concrete-operational reasoning and formal-operational reasoning) and a measure of spatial relations (the Revised Minnesota Paper Form Board Test). While a path analysis showed there were logically expected relationships among the tasks, neither sex differences nor age differences were found on any of the measures.
对15至19岁的高中生（N = 116）进行了三项皮亚杰式任务（重量守恒、具体运算推理和形式运算推理的纸笔测试）以及一项空间关系测量（修订版明尼苏达纸型板测试）。虽然路径分析表明任务之间存在逻辑上预期的关系，但在任何一项测量中均未发现性别差异和年龄差异。
