Poster #200 - Preschoolers Use Supply and Demand Relations to Make Judgments of Ease and Difficulty

• In Event: 1-169 - Poster Session 04
  In Poster Session: PS 04 Section - Social Cognition

Integrative Statement

A basic understanding of supply and demand can guide judgments about the relative difficulty of acquiring resources. For example, this understanding allows us to infer that it will be more difficult to obtain one of the few highly-sought parking spots near the entrance to a mall, compared with one of the plentiful, but less-popular, spots far from the entrance. Previous studies have found that an understanding of supply and demand in relation to prices and sales first emerges at around age 4 and solidifies between ages 8 to 13 (Berti & Grivet, 1990; Leiser, 1983; Leiser, Sevon, & Levy, 1990; Siegler & Thompson, 1998). However, no studies have examined whether preschoolers use supply and demand relations to make judgements of ease and difficulty. We examined whether they can do this in three experiments.
In Experiment 1, 3-4-year-olds (N=80) listened to two stories in which two flags were in a field, with treats around each flag (see Figure 1). Two groups of characters went to obtain treats at each flag. Children saw one of two versions of the stories. In the “different-supply” condition, one flag had more treats than the other, and equal numbers of characters went to each flag. In the “different-demand” condition, both flags had the same numbers of treats, but more characters went to one flag. Finally, a new character appeared, and children were asked where this character should go to get a treat. We examined children’s choices of the side with more supply or demand using a Generalized Estimating Equations (GEE) model. It revealed a main effect of Condition, p < .001, a main effect of Age, p = .013, and a Condition by Age interaction, p = .025. Children were more likely to choose the side-with-more in the different-supply condition than in the different-demand condition, and these differences were generally more pronounced among 4-year-olds than among 3-year-olds (see Figure 2).
In Experiments 2 and 3, 3-year-olds (N=60 per experiment) saw stories that were nearly identical to those from the different-supply condition and different-demand condition of Experiment 1, respectively. However, after the characters went to get treats from each flag, children were either asked where it would be easier to get treats or where this would be harder (question manipulated between-subjects). GEE models revealed that children were more likely to choose the high-supply side and low-demand side in the easier condition than in the harder condition, ps < .001. When asked where getting treats would be easier, children mostly indicated the high-supply and low-demand sides, ps ≤ .003; when asked where this would be harder, they mostly indicated the low-supply side, p = .024, but not the high-demand side, p = .178.
Together, these findings demonstrate that preschoolers as young as age 3 can use supply and demand ratios to make judgements about the ease and difficulty of acquiring objects. The findings also highlight that supply and demand reasoning has many uses outside of thinking about prices.

Authors

• Michelle Huh, University of Waterloo
  Presenting Author

• Ori Friedman, University of Waterloo
  Non-Presenting Author