BetaBinomial: The Beta-binomial Distribution

In brms: Bayesian Regression Models using 'Stan'

The Beta-binomial Distribution

Description

Cumulative density & mass functions, and random number generation for the Beta-binomial distribution using the following re-parameterisation of the Stan Beta-binomial definition:

• mu = alpha * beta mean probability of trial success.

• phi = (1 - mu) * beta precision or over-dispersion, component.

Usage

dbeta_binomial(x, size, mu, phi, log = FALSE)

pbeta_binomial(q, size, mu, phi, lower.tail = TRUE, log.p = FALSE)

rbeta_binomial(n, size, mu, phi)

Arguments

x, q	Vector of quantiles.
size	Vector of number of trials (zero or more).
mu	Vector of means.
phi	Vector of precisions.
log	Logical; If TRUE, values are returned on the log scale.
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.
n	Number of draws to sample from the distribution.

brms documentation built on Sept. 26, 2023, 1:08 a.m.