Use-case

The Likelihood Ratio defines a Discriminant Function without biases (priors) in the context of a Bayesian classifier.

Mathematical Definition

For a two class case,

Variants of the threshold:

  • Maximum Likelihood Decision

Simple decision

  • Bayes Decision

Makes use of Prior

  • Bayes Risk Decision

Use Prior and Cost

Note: is the cost of deciding state given state is true, so an and so forth.

Note: The threshold has same units as the axis.


References

Source