Understanding Probability

Colloquium | October 9 | 12:10-1:10 p.m. | 3105 Tolman Hall

 Shaun O'Grady, Dept. of Psychology

 Department of Psychology

What is the mental representation of probability and how does it develop? What role do education and experience play in understanding probability? In this talk I will present the results of 4 Experiments investigating probability judgments in children and adults. In the first part of the discussion I will present data from adult participants performing a ratio comparison task as well as a psycho-physical model designed to account for the role of non-numerical features in ratio representations. Findings revealed that people represent the probability of binary outcomes as proportions calculated over Approximate Number System representations. In the second portion of the talk I will discuss the developmental trajectory of these computational abilities in children and young teens. Data from 6- to 12-year-old children suggest that by the age of 7-8 years of age, children can accurately represent probabilities based on proportions and that the accuracy of probability judgments improves to match adult levels around the age of 12. Interestingly, this is around the same age that children are formally introduced to probability based on the Common Core State Standards. Finally, in the third section of the talk I will discuss the interacting roles of individual experience and culture on learning probability. Preliminary findings from 2 ongoing experiments reveal that children use heuristic rules to make binary probability judgments and that these rules can be overridden with an adequate amount and type of feedback. Together, these findings shed light on how the mind represents probability and how this representation is influenced by experience and culture.