How to find bias in library

Question

[Nhan]

I want to estimate bias in my library. i.e I want to quantify how equally distributed the variants are. In the case of non equal distributions I want to know which variants contribute to this non uniform distribution. How is this normally quantified?

EDIT: A bit more context. I have a collection of variants of the same virus in ~50k. I'm running an AmpSeq assay and want to understand bias towards any of the variants.

[Asaf]

It will help if you gave some background like what is the data you are working on etc.

[Nhan]

Added some context to the question