How to estimate a proper depth from the biom summary table?

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Ali shojaee Bakhtiari

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Apr 12, 2016, 3:01:42 PM4/12/16
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In the following link the authors somehow decided on 114 to be the ideal deapth

and claiming that it was deduced from the summary table. Now I have a summary table of my own. How am I supposed to guess the proper depth from it? mean minus one std perhaps? Is there a stnadard process?

Thanks

Colin Brislawn

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Apr 12, 2016, 11:23:24 PM4/12/16
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Good evening,

First, a small correction: the authors chose 1114 to be a good depth. 114 reads per sample (10x less) would probably too little in most situations.

Before they choose 1114 to be the cutoff, the authors ran the script 'biom summarize-table'. Have you ran this script yet? It shows you how many reads are in each of your samples. After seeing seeing, this you get to choose which samples to keep and which ones you want to throw away. Like the author say, "so this is always a trade-off between the number of sequences you throw away and the number of samples you throw away."

What does your 'biom summarize-table' look like for your data?

Colin Brislawn

Ali shojaee Bakhtiari

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Apr 13, 2016, 10:08:15 AM4/13/16
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Thanks Colin for the reply and the correction. 
The following is the stats of my biom summary table:
$$$$$
Num samples: 4788
Num observations: 45383
Total count: 25894245
Table density (fraction of non-zero values): 0.019

Counts/sample summary:
 Min: 1.0
 Max: 87836.0
 Median: 4445.000
 Mean: 5408.155
 Std. dev.: 4605.644
 Sample Metadata Categories: None provided
 Observation Metadata Categories: Consensus Lineage
$$$$
Mean minus one std leads to about 1000. That where I started from.
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