Developmental changes in probabilistic reasoning: The role of cognitive capacity, instructions, thinking styles and relevant knowledge.

In three experiments we explored developmental changes in probabilistic reasoning, taking into account the effects of cognitive capacity, thinking styles, and instructions. Normative responding increased with grade levels and cognitive capacity in all experiments, and it showed a negative relationship with superstitious thinking. The effect of instructions (in Experiments 2 and 3) was moderated by level of education and cognitive capacity. Specifically, only higher-grade students with higher cognitive capacity benefited from instructions to reason on the basis of logic. The implications of these findings for research on the development of probabilistic reasoning are also discussed.