Pairwise comparison of regions of enrichment in nanogram- and picogram-scale libraries. Each panel depicts a single pairwise comparison: ng and pg1, ng and pg2, and pg1 and pg2. Coverage of each region of enrichment in one sample (color-coded in the plots) by the regions of enrichment identified in another sample was computed as described in Methods. Then, the fractions of the total number of the regions of enrichment with coverage above the specified threshold were computed and presented in plots (solid lines). Since some regions of enrichment are not reproduced at all in different libraries, the same fractions were computed for the regions that have non-zero coverage (dashed lines) to address possible bias in the analysis.