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pythonrandompoissonpymcmcmc

Meaning of a variable declaration in PyMC

In this tutorial http://pymc-devs.github.io/pymc/tutorial.html#an-example-statistical-model ,

disasters = Poisson('disasters', mu=rate, value=disasters_array, observed=True)

this line denotes that disasters is a poisson random variable or disasters is a collection of poisson random variables, ith random variable has parameter = rate[i] (i.e each rv is drawn from a different random process with psrsmeter given by rate[i] )

How should I interpret this line ?

Solution

  • You can think of disasters as a list of the D_t random variables defined as equation 1:

    disasters = [D_1851, D_1852, ..., D_1962]

    It is not a python list, however, it is a pymc.stochastic, so this analogy will not work in all situations.