Comparison of Ratios and the Chance Concept in Children

Yost, Siegel, and Andrews (1962) and Goldberg (1966), following some investigations of Piaget (1950) and Piaget and Inhelder (1951), concluded that preschool children in decision-making situations are able to make appropriate probabilistic judgments. Davies (1965) studied practically the same problem in 3to 9-year-olds. Using a somewhat different technique, he found that the grasp of the probability concept is a progressive process and that nonverbal probabilistic behaviors precede verbal ones. In the experiment we devised, a decision-making technique was used in order to study a variety of variables. 1. In contrast with the aims of Yost et al. (1962) and Goldberg (1966), our goal was a systematic exploration of the evolution with age of the three major stages: (a) the preoperational, (b) the concrete operational, and (c) the formal operational. 2. In the technique of Yost et al. and of Goldberg, the Ss had to choose between two sets with the same number of chips for one of the two colors (e.g., four blue, one white; four blue, 16 white). We used, as will be seen, three categories of trials in order to extend the scope of our investigation. 3. Since all the above-mentioned experiments were limited to the investigation of spontaneous behavior, we thought it of interest to study the effects of prior systematic instruction.