Poisson

class pyhf.probability.Poisson(rate)

Bases: pyhf.probability._SimpleDistributionMixin

The Poisson distribution with rate parameter rate.

Example

>>> import pyhf
>>> rates = pyhf.tensorlib.astensor([5, 8])
>>> pyhf.probability.Poisson(rates)
<pyhf.probability.Poisson object at 0x...>

__init__(rate)

Parameters:

rate (tensor or float) – The mean of the Poisson distribution (the expected number of events)

Methods

expected_data()

The expectation value of the Poisson distribution.

Example

>>> import pyhf
>>> rates = pyhf.tensorlib.astensor([5, 8])
>>> poissons = pyhf.probability.Poisson(rates)
>>> poissons.expected_data()
array([5., 8.])

Returns:

The mean of the Poisson distribution (which is the rate)

Return type:

Tensor