The current study examined the stability of temperament over time. Observers and mothers rated child behavior at eight timepoints across three assessment waves (8, 15, and 30 months of age). Internal consistency reliability of aggregates of the eight observer reports and eight mother reports were high. When considering single timepoint…

Growth mixture modeling (GMM) is a method for identifying multiple unobserved sub-populations, describing longitudinal change within each unobserved sub-population, and examining differences in change among unobserved sub-populations. We provide a practical primer that may be useful for researchers beginning to incorporate GMM analysis into their…

Analyzes multiple components of planning, including problem representation, goal selection, a decision to plan, strategy choice, strategy execution, and monitoring. Analyzes three tasks typically used to study planning: the Tower of Hanoi; errand scheduling; and story comprehension. Argues that the components required to perform a planning task…