Sampling depth (also called sequencing depth or → library size) is the number of sequenced bases for a given sample. Increase in sampling depth in recent yearsShotgun metagenomic sequencing  human gut
Average sample size of wholegenome sequencing (WGS) samples of human gut metagenomes deposited at the NCBI short read archive. Median run size of each study was chosen to avoid dominating the results by larger studies.
How deep is enough for metagenomic shotgun sequencing?It's a balance between sampling depth and number of samples (for a given budget).
See also:
Read more Ni et al., 2013. Scientific Reports Statistical sample sizes and power calculations

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Sampling depth
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