ESTIMATING THE PROBABILITY OF OCCURRENCE OF TUMOR FOR A RARE CANCER WITH ZERO OCCURRENCE IN A SAMPLE

In many physical situations one needs to estimate the probability of o ccurrence of a rare event based on a random sample when the event has not occurred at all. For example, if the true Lifetime incidence of a tumor at a particular tissue site is less than 1%, it is not uncommon to observe no tumors in a typical sample size of 50 animals. This pape r explores the suitability of nonzero Bayesian estimation procedures t o replace zero maximum likelihood estimates for tissue sites with nonz ero background tumor incidences. (C) 1996 Academic Press, Inc.