Variant distance bias (VDB) in VCF format: how to compute properly?

Question

[Matteo Schiavinato]

Hi guys,

Does anyone of you have experience with computing the variant distance bias (VDB) value for VCF-formatted files?

I am trying to figure out myself how to do it, but literature / documentation / discussion on it is quite scarce.

So far, what I know is:

• The higher the value, the bigger the bias is
• 0 = no bias
• It has to be a float

What is the range for such value? Does anyone have a ready-to-go formula to use? Are there any established rules of thumb that one can use to understand it?

I'm sorry if this question is trivial for someone, I'm a bit lost.

Thanks!

EDIT:

• The range is [0,1] as a likelihood

[michael]

See Vdb Field In Samtools for a discussion of this