R: Hurdle Distributions

Hurdle {brms} | R Documentation

## Hurdle Distributions

### Description

Density and distribution functions for hurdle distributions.

### Usage

    dhurdle_poisson(x, lambda, hu, log = FALSE)

    phurdle_poisson(q, lambda, hu, lower.tail = TRUE, log.p = FALSE)

    dhurdle_negbinomial(x, mu, shape, hu, log = FALSE)

    phurdle_negbinomial(q, mu, shape, hu, lower.tail = TRUE, log.p = FALSE)

    dhurdle_gamma(x, shape, scale, hu, log = FALSE)

    phurdle_gamma(q, shape, scale, hu, lower.tail = TRUE, log.p = FALSE)

    dhurdle_lognormal(x, mu, sigma, hu, log = FALSE)

    phurdle_lognormal(q, mu, sigma, hu, lower.tail = TRUE, log.p = FALSE)

### Arguments

`x` | Vector of quantiles.
`hu` | hurdle probability
`log` | Logical; If `TRUE`, values are returned on the log scale.
`q` | Vector of quantiles.
`lower.tail` | Logical; If `TRUE` (default), return P(X <= x). Else, return P(X > x) .
`log.p` | Logical; If `TRUE`, values are returned on the log scale.
`mu, lambda` | location parameter
`shape` | shape parameter
`sigma, scale` | scale parameter

### Details

The density of a hurdle distribution can be specified as follows. If x = 0 set f(x) = θ. Else set f(x) = (1 - θ) * g(x) / (1 - G(0)) where g(x) and G(x) are the density and distribution function of the non-hurdle part, respectively.

[Package brms version 2.16.1 Index]