Betageom {VGAM} | R Documentation |
Density, distribution function, and random generation for the beta-geometric distribution.
dbetageom(x, shape1, shape2, log=FALSE) pbetageom(q, shape1, shape2, log.p=FALSE) rbetageom(n, shape1, shape2)
x, q |
vector of quantiles. |
n |
number of observations. Must be a positive integer of length 1. |
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) .
|
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.
dbetageom
gives the density,
pbetageom
gives the distribution function, and
rbetageom
generates random deviates.
pbetageom
can be particularly slow.
T. W. Yee
## 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=paste("Y ~ Beta-geometric(shape1=",shape1,", shape2=",shape2,")", sep="")) sum(proby) ## End(Not run)