Draw a random sample from a zero-inflated negative binomial distribution

Usage

# S3 method for class 'ZINegativeBinomial'
random(x, n = 1L, drop = TRUE, ...)

Arguments

x: A ZINegativeBinomial object created by a call to ZINegativeBinomial().
n: The number of samples to draw. Defaults to 1L.
drop: logical. Should the result be simplified to a vector if possible?
...: Unused. Unevaluated arguments will generate a warning to catch mispellings or other possible errors.

Value

In case of a single distribution object or n = 1, either a numeric vector of length n (if drop = TRUE, default) or a matrix with n columns (if drop = FALSE).

Examples

## set up a zero-inflated negative binomial distribution
X <- ZINegativeBinomial(mu = 2.5, theta = 1, pi = 0.25)
X
#> [1] "ZINegativeBinomial(mu = 2.5, theta = 1, pi = 0.25)"

## standard functions
pdf(X, 0:8)
#> [1] 0.46428571 0.15306122 0.10932945 0.07809246 0.05578033 0.03984309 0.02845935
#> [8] 0.02032811 0.01452008
cdf(X, 0:8)
#> [1] 0.4642857 0.6173469 0.7266764 0.8047688 0.8605492 0.9003923 0.9288516
#> [8] 0.9491797 0.9636998
quantile(X, seq(0, 1, by = 0.25))
#> [1]   0   0   1   3 Inf

## cdf() and quantile() are inverses for each other
quantile(X, cdf(X, 3))
#> [1] 3

## density visualization
plot(0:8, pdf(X, 0:8), type = "h", lwd = 2)


## corresponding sample with histogram of empirical frequencies
set.seed(0)
x <- random(X, 500)
hist(x, breaks = -1:max(x) + 0.5)