dzagamma2: Zero-augmented gamma probability density
In JimmyClowes/rethinking: Statistical Rethinking book package

Description Usage Arguments Details Author(s)

Function for computing density from a zero-augmented gamma probability distribution.

1	dzagamma2( x , prob , mu , scale , log=FALSE )

`x`	Values to compute densities for
`prob`	Probability of a zero
`mu`	Mean of gamma distribution
`scale`	Scale parameter (same as `scale` in `dgamma`)
`log`	If `TRUE`, returns log-density instead of density

This distribution is defined as a finite mixture of zeros and strictly positive gamma distributed values, where prob determines the weight of the zeros. As such, the probability of a zero is prob, and the probability of a non-zero value x is (1-prob)*dgamma( x , mu/scale , scale ).

Richard McElreath

JimmyClowes/rethinking documentation built on Dec. 18, 2021, 1:36 a.m.