BetaBinomial {brms} R Documentation

## 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.

[Package brms version 2.17.0 Index]