**hypergeom** function

hypergeom(Pop, Mark, Sample)

Returns a deviate from a hypergeometric distribution for a given population, number of marks, and size of sample.

Inputs: Population size (int), number of marked individuals (int), size of sample from population (int)

Outputs: deviate of number of marked individuals from sample

The hypergeometric distribution tells us the range of probabilities of getting a number of "marked" individuals when taking a sample of a certain size from a population, a given number of which are "marked".

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 research process involves ringing a certain number of seabirds from a population and releasing them, then at a later date recapturing a different number of the birds and checking how many ringed individuals are retreived. If a random group of individuals are captured each time, the probability of getting n rings back is equal to the probability of getting the result n from the equation:

rings_retrieved = hypergeom(Seabird_population, Birds_ringed, Birds_caught)

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

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