“…The pooled value, typically computed as the arithmetic mean of all the individual responses, has been considered to be a reasonable and practical, although not perfect, measure to summarize large complex data. [1][2][3][4][5][6][8][9][10][11] In the previous paper, 5 the authors had to plot only pooled values, because they considered it unrealistic to illustrate the entirety of such large complex data in the limited space of a conventional line graph, bar graph, or table. It should be noted that, such pooling intrinsically obscures the variations among observers or images, which may also be an important finding of an experiment in regard to the reliability in observers' subjective judgments.…”