Probability of the variant

A probability value is reported for each variant call in the variant track table column with the header "Probability". For the Fixed Ploidy Variant Caller this value is the posterior probability of the site being different from the homozygous reference site. This is possible to calculate because the model behind the Fixed Ploidy Variant Caller is Bayesian. As the model for the Low Frequency Variant Caller is not a Bayesian model, such a value strictly speaking does not exist. However, as a proxy for such a value we report the support for the winning model $ m$ relative to the total support of all models:

$\displaystyle P_m = \frac{e^{v_m}}{\sum_{m^{\prime}} e^{v_{m^{\prime}}}} $