How to Use the POISSON Function in Excel
Below is a comprehensive guide on how to use the POISSON function in Microsoft Excel and Google Sheets.
Overview
The POISSON function is utilized to calculate the Poisson distribution, a key tool in statistics. It helps to estimate the likelihood of a specific number of events occurring within a defined interval, either in time or space.
Syntax
The syntax for the POISSON function is as follows:
POISSON(x, mean, cumulative)x: The number of events.mean: The expected average number of events (mean).cumulative: A boolean value which specifies the type of distribution function to return. If set to TRUE, it calculates the cumulative distribution function; if FALSE, it returns the probability mass function.
Examples
Example 1: Calculating Probability Mass Function
Consider a scenario where we need to calculate the probability of observing 2 events given the average event rate is 1.5.
| x | Mean | Probability Mass Function |
|---|---|---|
| 2 | 1.5 | =POISSON(2,1.5,FALSE) |
Use the formula =POISSON(2,1.5,FALSE) in Excel/Google Sheets to perform this calculation.
Example 2: Calculating Cumulative Probability
To find the cumulative probability of observing up to 3 events when the mean is 2:
| x | Mean | Cumulative Probability |
|---|---|---|
| 3 | 2 | =POISSON(3,2,TRUE) |
Enter the formula =POISSON(3,2,TRUE) in Excel/Google Sheets for this computation.
This guide provides a clear basis for using the POISSON function in Excel and Google Sheets to perform statistical calculations effectively.
More information: https://support.microsoft.com/en-us/office/poisson-function-d81f7294-9d7c-4f75-bc23-80aa8624173a