Random count data from a discrete gamma distribution

For count data that is under-dispersed we can use a gamma distribution rounded to the nearest whole number. This is the same as the method of discretisation in make_gamma_ip, and suits delay distributions where there is less variability than can be represented with a Poisson or negative binomial distribution.

Usage

rdiscgamma(n, mean, sd, kappa)

Arguments

n

number of observations

mean

the mean value on the true scale (vectorised)

sd

the standard deviation on the true scale (vectorised)

kappa

a coefficient of variation. where 0 is no variability and 1 is maximally variability (vectorised)

Value

an integer valued vector from a gamma distribution.

See also

stats::rgamma()

Examples

rdiscgamma(10, 2, 1)
#>  [1] 1 2 1 2 1 1 1 2 3 2