As someone who completed their PhD in biometrics, they do not use heuristics to authenticate. Though that terminology is very broad. There's usually a match sco

As someone who completed their PhD in biometrics, they do not use heuristics to authenticate. Though that terminology is very broad. There's usually a match score threshold which is a heuristic based on some measured false acceptance rate, but with regards to determining the actual match score - it's often much more complex than a few heuristics.