Hi Jerson,

There are a couple ways of doing this.

You can use Focus > Analysis > Overlay > Statistical. The primary input layer is the polygon layer; the secondary layer is the raster channel. You would need to compute the Std Dev and Mean separately, then use Field > Compute in the Attribute Manager to compute the coefficient of variation (Std Dev / Mean).

You could also use VIMAGE to compute the Std Dev and Mean.

Another formula for CV (as a percentage):

Coefficient of Variation = (Standard Deviation / Mean) * 100

Hope this helps!

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