Preprint #96-18



That Probabilities Rather than Likelihoods Should be Maximized

by

C. Philip Cox


Abstract

Parameters of models posited for discrete variates are estimated by maximizing the joint probabilities of occurrence for the observed discrete values. The corresponding procedure for continuous variates is to maximize likelihood, a quantity which approximates the joint probability of occurrence when multiplied by appropriate differentials. Discussion of an example in the context of `compound' linear regression - wherein `measurement' variability attends both the x and y variables - shows that maximizing likelihood can be misleading and that the deficiency can be avoided by maximizing the approximate joint probability of occurrence.


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