why likelihood is not always a density? is likelihood a density function? why is likelihood not always a density function why is density in probability and likelihood why is probability a density function why is probability always a density function why is probability a density function why is the likelihood function a density function why is likelihood and evidence a density why is the probability density function necessary why is likelihood a density function why is likelihood a density function in machine learning why is the probability function of prior to likelihood a density function why is probability density not needed why are probability density functions necessary is probability always a density why is probability density a constant why is probability density a constant why is likelihood not always a density function for Bayesian data? why does likelihood not always be a density function