Minimum detectable effect size for main outcomes (accounting for sample
design and clustering)
We set power to 80% and the significance level to p=.05. Under these assumptions the standardized minimum detectable effect size (MDSE) is 0.25 on literacy skills (mean difference of 3.75 with a SD of 15 on PPVT). Assuming the measure of curiosity has 8 chances to choose a novel or familiar item, the MDSE is 0.25 (mean difference of 0.33 with a SD of 1.33 given a normal distribution from 0 to 8). Furthermore, assuming the measures of curiosity contain measurement error with a reliability coefficient R of 0.75, the calculation of the attenuated effect size from Phillips and Jiang (2016) gives a MDSE of around 0.29.