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[Bioc-devel] Deseq2 and differentia expression

hi Jarod,
On Thu, Jul 10, 2014 at 7:59 AM, jarod_v6 at libero.it <jarod_v6 at libero.it> wrote:
The code above does the selection on adjusted p-value. The right FDR
cutoff is up to you, what percent of false discoveries is tolerable in
the final list of genes? The considerations are: the cost of
validation or following up on a false discovery, versus the cost of a
missed discovery. These are hard to quantify even if you know all the
details of an experiment.
yes. The which() is necessary because some of the res$padj have NA. If
you have a logical vector with NA, you cannot directly index a
DataFrame, but you can index after calling which(), which will return
the numeric index of the TRUE's. You could also subset with:
subset(res, padj < 0.1).

The reason for the NAs is explained in the vignette: "Note that some
values in the results table can be set to NA, for either one of the
following reasons:..."
This is not the recommended way to filter on large log fold changes.
We have implemented a test specifically for this, check the vignette
section on "Tests of log2 fold change above or below a threshold"

Mike