Kramer J A, Hill K T, Cohen L B
Child Dev. 1975 Mar;46(1):149-55. doi: 10.1111/j.1467-8624.1975.tb03285.x.
To investigate Piaget's theory of object concept development, a series of 6 tasks was administered in a combined longitudinal/cross-sectional design incorporating a number of methodological controls. The tasks spanned the entire sensorimotor period and included single versus sequential displacements combined with visible or invisible hidings. 36 infants from 5 to 32 months of age at initial testing were drawn equally from day-care and home settings. All infants received the 6 tasks during each of 3 testing sessions over a 6-month period. Clear evidence was obtained for task ordinality as proposed by Piaget, with ordinality coefficients ranging from .71 to .82 for the 3 testing sessions. Performance changes across the 3 sessions were also ordinal in 80% of the cases. Expected age, task, and session effects and accompanying interactions were also obtained.
为了研究皮亚杰的客体概念发展理论，采用了一系列6项任务，以纵向/横断面相结合的设计进行，并纳入了一些方法学上的控制措施。这些任务涵盖了整个感知运动阶段，包括单次与连续位移，以及可见或不可见的隐藏方式。最初测试时年龄在5至32个月的36名婴儿，平均来自日托和家庭环境。在6个月的时间里，所有婴儿在3次测试中的每次测试中都接受了这6项任务。获得了明确的证据支持皮亚杰提出的任务顺序性，3次测试的顺序系数范围为0.71至0.82。在80%的案例中，3次测试中的表现变化也是有序的。还获得了预期的年龄、任务和测试效应以及伴随的相互作用。
