According to edgeR package, I can estimate the dispersion of my dataset using:
y <- estimateDisp(y, design, robust=TRUE)
The square root of the common dispersion gives the coefficient of biological variation. And, the dispersion estimates can be viewed in a BCV plot:
How do I know the function that generate this graph?
I need to know the coordinates (x,y) of the vertex (max and min value of "trend" in the Y-axis to each vertex) of the "trend dispersion" and the values of X where the "trend" (blue) intercepts the commun dispersion line (red)
Don´t worry about the spread of the data, the high variability is expected in my case.
Moderator edit: Here's a link to the BCV plot: