This function generates n_mcsim Poisson-distributed data sets
according to the parameters in the input table, and calculates the value of
the scan statistic for each generated data set using the supplied
zones.
poisson_mcsim(table, zones, n_mcsim = 999L)A data.table with columns location, duration, mu.
A set of zones, each zone itself being a set
containing locations. Locations should be encoded as integers.
A positive integer; the number of replicate scan statistics to generate.
A numeric vector of length n_mcsim.