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…

Are children intellectually impaired as a result of low birth weight and does relative impairment change as children grow older? Premature infants from a range of socioeconomic groups were studied in five rounds over 13 years to provide neurological, psychological, achievement, and sociological data on 582 children in three birth weight groups. A…