Syntax. POISSON.DIST(x,mean,cumulative)

Definition. This function returns the probabilities of a Poisson distributed random variable. A common application of the Poisson distribution is the prediction of the number of events over a specific time period such as the number of calls a call center receives within an hour.


  • x (required). The number of events.

  • mean (required). The expected numeric value.

  • cumulative (required). The logical value that represents the type of the function. If cumulative is TRUE, POISSON.DIST() returns the cumulative Poisson probability that the number of random events occurring will be between zero and x inclusive. If cumulative is FALSE, the function returns the probability that the number ...

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