This shows, why the choice of prior probabilities does not affect
the overall detector behavior - for any prior probability P(skin) it is
possible to choose the appropriate value of K, that gives the same
detection threshold Θ. It is also clear, that maximum likelihood
(ML) and maximum a posteriori (MAP) Bayes classification rules
compared in [Zarit et al. 1999] are equivalent to (14) with different
Θ values.