Poissonization

English Alternative forms en Poissonisation British spelling Etymology en Poisson ization. Noun - s en math combinatorics Analysis of a multivariate combinatorial distribution by turning interdependent variables into independent Poisson distributions. Examples When randomly allocating balls into urns, each urn has an expected balls. As , discrete rounds are 'blurred' into continuous time and the distribution of in an individual bin converges to a Poisson distribution, while as , covariance between two urns' counts is negligible except in extreme cases whose probability is asymptotically negligible. By Poissonization, the chance of all bins being filled (the coupon collector's problem) is ; if , this becomes , so to have a chance of filling them all (with close to ), the expected number of balls is . When considering a single urn among the set, Poissonisation becomes an exact method, such as in this math.se question. Some authors use the term to refer specifically to this. External links Poissonization at NIST's Dictionary of Algorithms and Data Structures