Poisson distribution

A Poisson distribution is defined by one parameter. This parameter has several names: lambda, the mean, the rate, the intensity, and the density. A physical interpretation is the average number of events during a time period of a specified duration.

With the Poisson distribution you can find the probability that a particular number of events will happen during a time period.

The probability distribution of the random variable X you see in the form of a bar chart and in the form of a table.

In the table you see the cumulative probability P(X>=k). By clicking in a cell of the table the accompanying part of the graph is colored in red.

There are three options available.

Cumulative

The bar chart is drawn cumulatively. The color connection between table and graph is not active now.

Normal approximation

The normal or cumulative normal distribution, whichever fits best, is drawn.

Boxplot

A boxplot is shown under the bar chart.