betabinom function

Beta-binomial distribution

Density and random generation for the Beta-binomial distribution with parameters size, mu, and theta.

rbetabinom(n = 1, size, prob, theta)

dbetabinom(x, size, prob, theta, log = FALSE)

Arguments

• n: integer; number of random variates to generate.
• size: size parameter of the binomial distribution
• prob: mean of the Beta distribution
• theta: Beta distribution dispersion parameter
• x: vector of non-negative integer quantiles
• log: logical; if TRUE, return logarithm(s) of probabilities.

Returns

• rbetabinom: Returns a vector of length n containing random variates drawn from the Beta-binomial distribution.

• dbetabinom: Returns a vector (of length equal to the number of columns of x) containing the probabilities of observing each column of x given the specified parameters (size, prob, theta).

Details

A variable $X$ is Beta-binomially distributed if $X~{Binomial(n,P)}$ where $P~Beta(mu,theta)$. Using the standard $(a,b)$ parameterization, $a=mu*theta$ and $b=(1-mu)*theta$.

C API

An interface for C codes using these functions is provided by the package. Visit the package homepage to view the c("list("pomp")", " C API document").

See Also

More on implementing POMP models: Csnippet, accumvars, basic_components, covariates, dinit_spec, dmeasure_spec, dprocess_spec, emeasure_spec, eulermultinom, parameter_trans(), pomp-package, pomp_constructor, prior_spec, rinit_spec, rmeasure_spec, rprocess_spec, skeleton_spec, transformations, userdata, vmeasure_spec