The shape of development

This project examines the shape of conceptual development from early childhood through adulthood. To do so we model the attainment of developmental complexity levels in the moral reasoning of a large sample (n = 747) of 5- to 86-year-olds. Employing a novel application of the Rasch model to investigate patterns of performance in these data, we show that the acquisition of successive complexity levels proceeds in a pattern suggestive of a series of spurts and plateaus. We also show that there are six complexity levels represented in performance between the ages of 5 and 86; that patterns of performance are consistent with the specified sequence; that these findings apply to both childhood and adulthood levels; that sex is not an important predictor of complexity level once educational attainment has been taken into account; and that both age and educational attainment predict complexity level well during childhood, but educational attainment is a better predictor in late adolescence and adulthood.