Bart, William M.Mertens, Donna M.2011-02-032011-02-031979Bart, William M & Mertens, Donna M. (1979). The hierarchical structure of formal operational tasks. Applied Psychological Measurement, 3, 343-350. doi:10.1177/014662167900300306doi:10.1177/014662167900300306https://hdl.handle.net/11299/99633The hierarchical structure of the formal operational period of Piaget’s theory of cognitive development was explored through the application of ordering theoretic methods to a set of data that systematically tapped the various formal operational schemes. The results suggest that the tasks within some schemes are empirically equivalent. While the response patterns were quite varied, the results do suggest that some common structure may underlie performance on the tasks, thus supporting Piaget’s notion of the integrative structure of the period.enArticle