DESeq2 model - exploring dispersions
NOTE: It may take a bit longer to load this exercise.
After fitting the model in the previous exercise, let's explore the fit of our smoc2 data to the negative binomial model by plotting the dispersion estimates using the plotDispEsts()
function. Remember that the dispersion estimates are used to model the raw counts; if the dispersions don't follow the assumptions made by DESeq2, then the variation in the data could be poorly estimated and the DE results could be less accurate.
The assumptions DESeq2
makes are that the dispersions should generally decrease with increasing mean and that they should more or less follow the fitted line.
This exercise is part of the course
RNA-Seq with Bioconductor in R
Exercise instructions
- Plot the dispersion estimates for the
smoc2
data using theplotDispEsts()
function. Assume all prior steps have been executed, including the creation of the DESeq2 object,dds_smoc2
and running theDESeq()
function.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
# Plot dispersions
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