Figure 5: Display of the results of the analysis of the sample dataset when subjects were divided into two groups with low and high language improvement. The left-most row of line graphs shows the same information as the line graphs of Figure 3 (except for 2 less subjects); the additional line-graphs show all effects including the new factor group. The interaction day by group shows a significant effect around 850 ms. Because there are more than two mean maps, the MDS figure now also contains a 𝑦 -axis that shows the projection of the mean maps onto the second eigenvector. The MDS indicates that the day by group interaction is mainly due to the differences between days 1 and 2 in poor learners; good learners show a much smaller change. The result suggests that from day 1 to day 2, poor learners have changed in late, feedback-related processing, while good learners have maintained their initial processing strategies. The same conclusion is also deducible from the mean maps shown in the upper right part of the display.