Fig. 5

Confidence as a function of performance (number of correct answers) across the 12 claims of exercises on vaccine efficacy and p value (N(A) = 756, N(B) = 756). The collected data are here mapped onto a probability scale from 50 (lowest confidence, the participant answered randomly) to 100 (maximal confidence judgment). This was done by applying the transformation / 2 + 50 to the collected confidence judgments. A Confidence judgments of all claims from both exercises were averaged for each participant to indicate their global confidence. The linear plot shows the mean progression of these individual global confidence levels in function of the participants’ respective performance (number of correct answers) across the two exercises. Error bars indicate standard error of the mean (SEM). The values above each mean point indicate the number of participants with X correct answers. Global reported confidence increases more rapidly than performance across exercises on vaccine efficacy and p value. B Confidence judgments plotted separately for correct and incorrect answers as a function of performance (number of correct answers). Error bars indicate SEM over participants. Values for participants with 0 and 1 correct answers were, respectively, plotted according to 3 and 2 participants’ data points. Overall, confidence in correct answers was significantly higher than in incorrect answers for all levels of performance superior to one correct answer