Fig. 2
From: aMeta: an accurate and memory-efficient ancient metagenomic profiling workflow
Schematic demonstration of the difference between depth and breadth/evenness of coverage concepts. Two read alignment scenarios, A and B, have an identical depth of coverage of Nreads* Lread / Lgenome = 4 * Lread / 4 * Lread = 1X. However, the reads are spread unevenly in case A and evenly in case B. The latter has a higher breadth of coverage (100% in contrast to 25% for the former) and evenness of coverage. Scenario B corresponds to a true-positive hit, while scenario A is typical of a false-positive microbial detection