Poisson distribution Orlaith Burke Alejandra Gonzalez-Beltran NIST: http://www.itl.nist.gov/div898/handbook/eda/section3/eda366j.htm Philippe Rocca-Serra Poisson distribution is a probability distribution used to model the number of events occurring within a given time interval. It is defined by a real number (λ) and an integer k representing the number of events and a function. The expected value of a Poisson-distributed random variable is equal to λ and so is its variance. dpois(x, lambda, log = FALSE) http://stat.ethz.ch/R-manual/R-patched/library/stats/html/Poisson.html http://docs.scipy.org/doc/scipy/reference/generated/scipy.stats.poisson.html#scipy.stats.poisson discrete probability distribution ready for release