Experts have argued that young children are generally overconfident in their abilities, understanding, and knowledge. However, many questions about self-overestimation in childhood remain unanswered. This dissertation aims to yield an in-depth understanding of children's self-overestimation by testing its variation across tasks, age, culture, and historical time, as well as its psychological underpinnings.
This dissertation reports on both primary research (i.e., two studies involving data from four samples), and secondary research (i.e., a meta-analytic review involving data from 39 publications of empirical studies). For each of these studies, biases in children's self-estimates were examined in a task-specific context by comparing differences between children’s subjective, prospective self-estimates and corresponding objective measures of actual performance. Specifically, two empirical studies employed an adapted prediction-performance paradigm to assess self-estimation of four- and five-year old children, applied in both a ball-throwing task and a picture-remembering task. For the ball throwing task, children marked their estimates of performance by placing a flag where they thought their (or another child’s) ball would land; and for the memory task, children left blank cards to mark their estimates of how many pictures they (or another child) would recall correctly. In addition, the empirical studies used a multiple-trial design yieding multiple measures of both children’s estimated and actual performance, to explore to what extent children learn from task experience and feedback. In one of the empirical studies (reported in Chapter 3), we employed experimental research methods to obtain causal evidence on the psychological process that accounts for why children overestimate themselves.
We found that children overestimate their task performance, and they do so to a similar degree for different types of tasks. Such self-overestimation is not a uniquely Western phenomenon: Dutch and Chinese children tended to show similar levels of self-overestimation. That said, we also found some cultural differences, in that Dutch children tended to be tenacious in their self-overestimation, while Chinese children were more inclined to realistically adjust their self-overestimation if the situation called for it. Younger children overestimated their task performance more than older children, and recent generations of children showed greater self-overestimation than previous generations. Our findings suggest that children’s self-overestimation is rooted in both (meta)cognitive and motivational factors. Cognitively, children are not always effective in incorporating performance-related information in their performance estimates; and motivationally, children’s performance estimates are sometimes colored by a desire for good performance.
Acknowledging self-overestimation as a common bias in children's self-representations offers valuable insight for parents, educators, and other professionals working with children. The finding that young children’s self-overestimation is pervasive, and generalizes across tasks and cultures, may suggest there is no reason for undue concern when self-overestimation is observed in an individual child. Theory suggests that self-overestimation in early childhood may be adaptive and benefit children’s potential for learning, but empirical evidence is virtually non-existent. Future research could examine the consequences of children's self-overestimation across various ages, to test the possibility that it is specifically young children who benefit from overestimating themselves.