Fig. 3
From: Quality filtering of Illumina index reads mitigates sample cross-talk
Breakdown of average quality scores by error type. Each point represents the reads obtain for one triplet (i5, i7, and sequence read), and is scaled to the log of the read count. Correct triplets (green) have high quality across all read steps, whereas sequence misassignments have low quality in all three read steps. In contrast, index misassignments tend to have low quality in the step for which they are misassigned