Decision Making Based On Internal And External Information (Codes and Supplementary Materials)

Title: Development Of Decision Making Based On Internal And External Information: A Hierarchical Bayesian Approach.
Authors: Jacqueline N. Zadelaar, Joost A. Agelink van Rentergema, Jessica V. Schaaf a, Tycho J. Dekkers, Nathalie de Venta, Laura M. S. Dekkerse, Riëtte Olthof , Brenda R. J. Jansen, Hilde M. Huizenga.

Abstract: In decision making, people may rely on their own information, as well as on information from external sources (e.g., family, peers, experts). The current study examined if and how both types of information are utilized by comparing four decision strategies: 1) an internal strategy (i.e., people solely rely on their own information); 2) an external strategy (i.e., people solely rely on the information from an external source); 3) a sequential strategy (i.e., people rely on either their own information and subsequently on that from an external source, if their own information deemed inadequate); 4) an integrative strategy (i.e., people’s own information and that of an external source are integrated to reach a decision). Strategy use was examined via Bayesian hierarchical mixture analysis. Study 1 featured an auditory discrimination task, administered to children (N=11, ages 6-11), adolescents (N=30, ages 12-17), and adults (N=25, ages 18-65). Study 2 entailed a visual discrimination task administered to children and young adolescents (N=305, ages 9-14). Age groups were compared on: 1) strategy use, 2) response accuracy, 3) response time. Strategies were assigned on an individual level, based on the posterior probability. BF values of strategy assignment were calculated using the Product space method.