title: Bayesian change-point analysis reveals developmental change in a classic theory of mind task.
abstract: Although learning and development reflect changes situated in an individual brain, most discussions of behavioral change are based on the evidence of group averages. Our reliance on group-averaged data creates a dilemma. On the one hand, we need to use traditional inferential statistics. On the other hand, group averages are highly ambiguous when we need to understand change in the individual; the average pattern of change may characterize all, some, or none of the individuals in the group. Here we present a new method for statistically characterizing developmental change in each individual child we study. Using false-belief tasks, fifty-two children in two cohorts were repeatedly tested for varying lengths of time between 3 and 5 years of age. Using a novel Bayesian change point analysis, we determined both the presence and-just as importantly-the absence of change in individual longitudinal cumulative records. Whenever the analysis supports a change conclusion, it identifies in that child's record the most likely point at which change occurred. Results show striking variability in patterns of change and stability across individual children. We then group the individuals by their various patterns of change or no change. The resulting patterns provide scarce support for sudden changes in competence and shed new light on the concepts of "passing" and "failing" in developmental studies.
authors: Department of Psychology and Center for Cognitive Science, Rutgers University, 152 Frelinghuysen Road, Piscataway, NJ 08854, USA; School of Experimental Psychology, University of Bristol, 12a Priory Road, Bristol BS8 1TU, UK; Faculty of Education, University of Cambridge, 184 Hills Road, Cambridge CB2 8PQ, UK. Electronic address: stb32@cam.ac.uk.
authors: Sara T
authors: ST
authors: Baker
authors: Department of Psychology and Center for Cognitive Science, Rutgers University, 152 Frelinghuysen Road, Piscataway, NJ 08854, USA.
authors: Alan M
authors: AM
authors: Leslie
authors: Department of Psychology and Center for Cognitive Science, Rutgers University, 152 Frelinghuysen Road, Piscataway, NJ 08854, USA.
authors: C R
authors: CR
authors: Gallistel
authors: School of Experimental Psychology, University of Bristol, 12a Priory Road, Bristol BS8 1TU, UK.
authors: Bruce M
authors: BM
authors: Hood
mesh_terms: D001499:Bayes Theorem; D002657:Child Development; D002675:Child, Preschool; D003210:Concept Formation; D005260:Female; D006801:Humans; D007206:Individuality; D008297:Male; D002666:Psychology, Child; D056345:Theory of Mind
keywords: Bayesian statistics; Change point analysis; Preschoolers; Theory of mind