Figure 2.

Adenine error rate. The observed error rate and predicted error rate after nonparametric regression are plotted for adenine by quality value for a single lane of Illumina sequencing of Megachile rotundata. The number of training instances at each quality value are drawn as a histogram below the plot. At low and medium quality values, adenine is far more likely to be miscalled as cytosine than thymine or guanine. However, the distribution at high quality is more uniform.