Fig. 3.

Pearson correlation coefficient between the log-likelihood of the top and bottom 50% of reviewing sequences of a learner under MEMORIZE and its associated empirical forgetting rate. The circles indicate median values and the bars indicate standard error. Lower correlation values correspond to greater gains due to MEMORIZE. To ensure reliable estimation, we considered learners with at least $70$ reviewing sequences with a training period $T=8\pm 3.2$ d. There were $322$ of such learners.