# betageomUC: The Beta-Geometric Distribution In VGAM: Vector Generalized Linear and Additive Models

 Betageom R Documentation

## The Beta-Geometric Distribution

### Description

Density, distribution function, and random generation for the beta-geometric distribution.

### Usage

dbetageom(x, shape1, shape2, log = FALSE)
pbetageom(q, shape1, shape2, log.p = FALSE)
rbetageom(n, shape1, shape2)

### Arguments

 x, q vector of quantiles.
 n number of observations. Same as runif. shape1, shape2 the two (positive) shape parameters of the standard beta distribution. They are called a and b in beta respectively. log, log.p Logical. If TRUE then all probabilities p are given as log(p).

### Details

The beta-geometric distribution is a geometric distribution whose probability of success is not a constant but it is generated from a beta distribution with parameters shape1 and shape2. Note that the mean of this beta distribution is shape1/(shape1+shape2), which therefore is the mean of the probability of success.

### Value

dbetageom gives the density, pbetageom gives the distribution function, and rbetageom generates random deviates.

### Note

pbetageom can be particularly slow.

### Author(s)

T. W. Yee

geometric, betaff, Beta.

### Examples

## Not run:
shape1 <- 1; shape2 <- 2; y <- 0:30
proby <- dbetageom(y, shape1, shape2, log = FALSE)
plot(y, proby, type = "h", col = "blue", ylab = "P[Y=y]", main = paste0(
"Y ~ Beta-geometric(shape1=", shape1,", shape2=", shape2, ")"))
sum(proby)

## End(Not run)

VGAM documentation built on Sept. 19, 2023, 9:06 a.m.