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Buit-in functions : poidev function

poidev function


Input: Real numerical values

Result: A value from the Poisson distribution with the given mean. A new random deviate is generated each time step.

The poisson distribution describes the probability of a given number of positive outcomes occurring in the limiting case of the binomial distribution, i.e., with very many trials each with a very small chance of a positive outcome.

This function is implemented using a pseudo-random sequence generator; notes regarding its behaviour can be found in the documentation for the rand_var function.

Example: A hospital serves a large community in which a certain percentage of individuals are thought to be carriers of the hospital superbug MRSA. If we admit a small number of individuals to hospital, we would expect the probability of getting a certain number of MRSA carriers in that group to be equal to the probability of getting that number as the result of this equation:

MRSA_positive_admissions = poidev(Total_admissions*MRSA_prevalence_percent/100)

In: Contents >> Working with equations >> Functions >> Built-in functions