Poster #32 - Pragmatic influences on 4- and 6-year-olds’ use of base-rates

• In Event: 3-003 - Poster Session 09
  In Poster Session: PS 09 Section - Cognitive Processes

Integrative Statement

When presented with the lawyer-engineer problem (Kahneman & Tversky, 1973), adults underuse base-rates in favor of case-specific individuating information. Participants often rely on individuating information in lieu of base-rates due to pragmatic aspects of the paradigm. Moreover, altering the pragmatics of the problem can lead to increases in adults’ base-rate use (Koehler, 1996; Schwarz et al., 1991). Recent work has shown that by age 6, children rely on individuating information at a rate similar to adults, though 4-year-olds consistently use base-rate information in their decisions (Gualtieri & Denison, 2018). Because children’s sensitivity to pragmatics increases with age, the current experiment explored the influence of pragmatic factors on 4- and 6-year-olds’ age-related use of base-rates.
Ninety-six 4- to 6-year-olds were tested. In all conditions, participants completed two trials in which they heard stories about children in a class doing activities. Participants were shown a base-rate of eight children completing one activity, and two children completing the other (i.e., eight kids made a craft and two played baseball; Figure 1). Following this, children were told about a particular child in the class. The individuating information provided about this child conflicted with the base-rate (i.e., if there were more children who made a craft, this child enjoyed physical activity). Children were asked what activity the child completed in class.
To explore the influence of pragmatics on children’s base-rate use, children participated in one of three between-subjects conditions. In the baseline condition, the amount of time spent on the base-rate and individuating information was modeled after the adult problem and the recent child problem, in which the individuating information was highly detailed. In the explained base-rate condition, an explanation was provided for the composition of the base-rate. That is, the role of personal preference in the base-rate composition was “explained away” (e.g., if more children made the craft, participants were told that it was because it was raining). In the reduced pragmatics condition, the time spent on the base-rate and individuating information was equated to ensure that both pieces of information were equally salient.
A Generalized Estimating Equation with age (4, 6) and condition (baseline, explained base-rate, reduced pragmatics) as between-subjects factors revealed a significant main effect of condition, Wald χ2(df=2)=10.81, p=.004, a marginal effect of age, Wald χ2(df =1)=3.43, p=.06, and a significant age by condition interaction, Wald χ2(df=2)=7.50, p =.02 (see Figure 2). Pairwise comparisons indicated a significant difference between 6-year-olds in the baseline and explained base-rate conditions (p=.03) and the baseline and reduced pragmatics conditions (p<.001). There was also a significant difference between 4s and 6s in the baseline condition (p<.001). Thus, while 4-year-olds were consistent with their base-rate use across conditions, 6-year-olds were affected by pragmatics. These findings provide the first insight on how pragmatics impact age differences in children’s use of base-rates and individuating information. 4-year-olds’ tendency toward base-rate use may be partly due to insensitivity to the pragmatics in the paradigm, while 6-year-olds’ base-rate neglect may partly lie in their attentiveness to these aspects.

Authors

• Samantha Gualtieri, University of Waterloo
  Presenting Author

• Stephanie Denison, University of Waterloo
  Non-Presenting Author