brms (version 2.19.0)

ZeroInflated: Zero-Inflated Distributions

Description

Density and distribution functions for zero-inflated distributions.

Usage

dzero_inflated_poisson(x, lambda, zi, log = FALSE)
pzero_inflated_poisson(q, lambda, zi, lower.tail = TRUE, log.p = FALSE)
dzero_inflated_negbinomial(x, mu, shape, zi, log = FALSE)
pzero_inflated_negbinomial(q, mu, shape, zi, lower.tail = TRUE, log.p = FALSE)
dzero_inflated_binomial(x, size, prob, zi, log = FALSE)
pzero_inflated_binomial(q, size, prob, zi, lower.tail = TRUE, log.p = FALSE)
dzero_inflated_beta_binomial(x, size, mu, phi, zi, log = FALSE)
pzero_inflated_beta_binomial(
  q,
  size,
  mu,
  phi,
  zi,
  lower.tail = TRUE,
  log.p = FALSE
)
dzero_inflated_beta(x, shape1, shape2, zi, log = FALSE)
pzero_inflated_beta(q, shape1, shape2, zi, lower.tail = TRUE, log.p = FALSE)

Arguments

x

Vector of quantiles.

zi

zero-inflation 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, shape1, shape2

shape parameter

size

number of trials

prob

probability of success on each trial

phi

precision parameter

Details

The density of a zero-inflated distribution can be specified as follows. If \(x = 0\) set \(f(x) = \theta + (1 - \theta) * g(0)\). Else set \(f(x) = (1 - \theta) * g(x)\), where \(g(x)\) is the density of the non-zero-inflated part.