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POISSON

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This function returns the Poisson distribution.

POISSON(*nevents*,*mean*,*cumulative*)

This function has these arguments:

Argument | Description |
---|---|

nevents |
Number of events Provide an integer, or the value is truncated. The number must be greater than zero. |

mean |
Expected numeric value The number must be greater than zero. |

cumulative |
Set to TRUE to return the cumulative Poisson probability that the number of random events occurring is between zero and nevents inclusive. Set to FALSE to return the Poisson probability mass function that the number of events occurring is exactly nevents. |

The cumulative Poisson probability is calculated as follows:

The Poisson probability mass function is calculated as follows:

where x is the number of events (*nevents* argument), mu is the mean (*mean* argument).

Accepts numeric data for all arguments. Returns numeric data.

POISSON(A3,B4,TRUE)

POISSON(R1C2,3,FALSE)

POISSON(7,4,TRUE) gives the result 0.948866384

POISSON(7,4,FALSE) gives the result 0.059540363

This function is available in product version 1.0 or later.

BINOMDIST | GAMMADIST | HYPGEOMDIST | Statistical Functions