This paper discusses research exploring the performance factors involved in studies which test for formal operations. It is suggested that several previous studies dealing with formal operations confound performance and competence in determining the extent of subjects' formal operations schemata. Factors which might account for performance…

The research described in this article addressed the question of why siblings commonly have different developmental outcomes despite their common beginnings. The studies analyzed behavioral development, especially through examination of deviant behaviors and intellectual development, by tracing siblings' different life histories. The work is based…

Analyzing data from the High School and Beyond survey on the behavior of 13,000 high school sophomore women over a two-year period, this document reveals the following facts about single motherhood: (1) young women with different background profiles exhibit markedly different rates of single parenthood; (2) because teenage women who become single…