trun.r: Generates Random Values from a Truncated Density Function of...

In gamlss.tr: Generating and fitting truncated (gamlss.family) distributions

Description

Creates a function to generate randon values from a truncated probability density function created from a current GAMLSS family distribution

For continuous distributions left truncation at 3 means that the random variable can take the value 3. For discrete distributions left truncation at 3 means that the random variable can take values from 4 onwards. This is the same for right truncation. Truncation at 15 for a discrete variable means that 15 and greater values are not allowed but for continuous variable it mean values greater that 15 are not allowed (so 15 is a possible value).

Usage

trun.r(par, family = "NO", type = c("left", "right", "both"), ...)

Arguments

par	a vector with one (for left or right truncation) or two elements for both
family	a gamlss.family object, which is used to define the distribution and the link functions of the various parameters. The distribution families supported by gamlss() can be found in gamlss.family. Functions such as BI() (binomial) produce a family object.
type	whether left, right or in both sides truncation is required, (left is the default)
...	for extra arguments

Value

Returns a r family function

Author(s)

Mikis Stasinopoulos [e-mail] and Bob Rigby [e-mail]

References

Rigby, R. A. and Stasinopoulos D. M. (2005). Generalized additive models for location, scale and shape,(with discussion), Appl. Statist., 54, part 3, pp 507-554.

Stasinopoulos D. M., Rigby R.A. and Akantziliotou C. (2003) Instructions on how to use the GAMLSS package in R. Accompanying documentation in the current GAMLSS help files, (see also http://www.gamlss.com/).

See Also

trun.p, trun.q, trun.d, gen.trun

Examples

# trucated r function
# continuous
#----------------------------------------------------------------------------------------
# left
test1<-trun.r(par=c(0), family="TF", type="left")
rr<-test1(1000)
hist(rr)
#----------------------------------------------------------------------------------------
# right
test2 <- trun.r(par=c(10), family="BCT", type="right")
rr<-test2(1000)
hist(rr)
#----------------------------------------------------------------------------------------
# both
test3<-trun.r(par=c(-3,3), family="TF", type="both")
rr<-test3(1000)
hist(rr)
#----------------------------------------------------------------------------------------
# discrete 
# trucated r function
# left
test1<-trun.r(par=c(0), family="PO", type="left")
tN <- table(Ni <- test1(1000))
 r <- barplot(tN, col='lightblue')
#----------------------------------------------------------------------------------------
# right
test2 <- trun.r(par=c(10), family="NBI", type="right")
tN <- table(Ni <- test2(1000))
 r <- barplot(tN, col='lightblue')
tN <- table(Ni <- test2(1000,mu=5))
  r <- barplot(tN, col='lightblue')
tN <- table(Ni <- test2(1000,mu=10, sigma=.1))
  r <- barplot(tN, col='lightblue')
#----------------------------------------------------------------------------------------
# both 
test3<-trun.r(par=c(0,10), family="NBI", type="both")
 tN <- table(Ni <- test3(1000,mu=5))
 r <- barplot(tN, col='lightblue')

gamlss.tr documentation built on May 2, 2019, 4:40 p.m.