Fig. 5
From: Researching for better instructional methods using AB experiments in MOOCs: results and challenges
Comparing the average number of correctly answered DPA problems in each DPA sequence. The total number of problems (beyond the 1st one or two that were used to select the sample) in each sequence is shown in Table 3. a Average number of correctly answered problems on first attempt. b Average number of problems answered correctly on second attempt. **Significant at 0.01 level. *Significant at the 0.05 level. †Significant at the 0.05 level, but population might be dissimilar