Poisson Command

Poisson[ <Mean> ]

Returns a bar graph of a Poisson distribution with given mean λ.

Poisson[ <Mean>, <Boolean Cumulative> ]

Returns a bar graph of a Poisson distribution when Cumulative = false.

Returns a graph of a cumulative Poisson distribution when Cumulative = true.

The first parameter is same as above.

Poisson[ <Mean>, <Variable Value v>, <Boolean Cumulative> ]

Let X be a Poisson random variable.

Returns P( X = v) when Cumulative = false.

Returns P( X ≤ v) when Cumulative = true.

First parameter is same as above.

Examples:

• Poisson[3, 1, true] yields 0.2 in the Algebra View and \frac{4}{e³} in the CAS View.
• Poisson[3, 1, false] yields 0.15 in the Algebra View and \frac{3}{e³} in the CAS View.