Suppose that Y1,....,Yn denote a random sample from the Poisson dist.pdf

The document discusses the Poisson distribution and finding the maximum likelihood estimator for P(Y=0). The Poisson distribution models the number of events occurring in a fixed interval of time or space if these events occur with a known average rate and independently of the time since the last event. The maximum likelihood estimator for P(Y=0), the probability of observing no events, is e^(-λ) where λ is the mean of the Poisson distribution.