Estimating meteor rates using Bayesian inference

A method for estimating the true meteor rate lambda from a small number of observed meteors n is derived. We employ Bayesian inference with a Poissonian likelihood function. We discuss the choice of a suitable prior and propose the adoption of Jeffreys prior, P(lambda)=lambda^-0.5, which yields an expectation value E(lambda) = n+0.5 for any n >= 0. We update the ZHR meteor activity formula accordingly, and explain how 68%- and 95%-confidence intervals can be computed.