Package 'gamlss.tr'

Title: Generating and Fitting Truncated 'gamlss.family' Distributions
Description: This is an add-on package to 'gamlss' which supports truncated distributions in Generalized Additive Models for Location Scale and Shape. The main function gen.trun() generates truncated version of an existing gamlss family distribution.
Authors: Mikis Stasinopoulos [aut, cre] , Robert Rigby [aut]
Maintainer: Mikis Stasinopoulos <[email protected]>
License: GPL-2 | GPL-3
Version: 5.1-9
Built: 2025-01-04 02:38:37 UTC
Source: https://github.com/gamlss-dev/gamlss.tr

Help Index


Generating and Fitting Truncated 'gamlss.family' Distributions

Description

This is an add-on package to 'gamlss' which supports truncated distributions in Generalized Additive Models for Location Scale and Shape. The main function gen.trun() generates truncated version of an existing gamlss family distribution.

Details

The DESCRIPTION file:

Package: gamlss.tr
Title: Generating and Fitting Truncated 'gamlss.family' Distributions
Version: 5.1-9
Date: 2024-03-29
Authors@R: c(person("Mikis", "Stasinopoulos", role = c("aut", "cre"), email = "[email protected]", comment = c(ORCID = "0000-0003-2407-5704")), person("Robert", "Rigby", role = "aut", email = "[email protected]", comment = c(ORCID = "0000-0003-3853-1707")) )
Description: This is an add-on package to 'gamlss' which supports truncated distributions in Generalized Additive Models for Location Scale and Shape. The main function gen.trun() generates truncated version of an existing gamlss family distribution.
License: GPL-2 | GPL-3
URL: http://www.gamlss.org/
BugReports: https://github.com/gamlss-dev/gamlss.tr/issues
Depends: R (>= 2.2.1), gamlss.dist, gamlss (>= 5.0-0), methods
LazyLoad: yes
Repository: https://gamlss-dev.r-universe.dev
RemoteUrl: https://github.com/gamlss-dev/gamlss.tr
RemoteRef: HEAD
RemoteSha: fffd73b641fc49d0eebf3a6debd417b03d162c1c
Author: Mikis Stasinopoulos [aut, cre] (<https://orcid.org/0000-0003-2407-5704>), Robert Rigby [aut] (<https://orcid.org/0000-0003-3853-1707>)
Maintainer: Mikis Stasinopoulos <[email protected]>

Index of help topics:

fitTail                 For fitting truncated distribution to the tails
                        of data
gamlss.tr-package       Generating and Fitting Truncated
                        'gamlss.family' Distributions
gen.trun                Generates a truncated distribution from a
                        gamlss.family
trun                    Fits a Truncate Distribution from a
                        gamlss.family
trun.d                  Truncated Probability Density Function of a
                        gamlss.family Distribution
trun.p                  Truncated Cumulative Density Function of a
                        gamlss.family Distribution
trun.q                  Truncated Inverse Cumulative Density Function
                        of a gamlss.family Distribution
trun.r                  Generates Random Values from a Truncated
                        Density Function of a gamlss.family
                        Distribution

Author(s)

Mikis Stasinopoulos [aut, cre] (<https://orcid.org/0000-0003-2407-5704>), Robert Rigby [aut] (<https://orcid.org/0000-0003-3853-1707>)

Maintainer: Mikis Stasinopoulos <[email protected]>

References

Rigby, R. A., Stasinopoulos, D. M., Heller, G. Z., and De Bastiani, F. (2019) Distributions for modeling location, scale, and shape: Using GAMLSS in R, Chapman and Hall/CRC. doi:10.1201/9780429298547 An older version can be found in https://www.gamlss.com/.

Stasinopoulos D. M. Rigby R.A. (2007) Generalized additive models for location scale and shape (GAMLSS) in R. Journal of Statistical Software, Vol. 23, Issue 7, Dec 2007, doi:10.18637/jss.v023.i07.

Stasinopoulos D. M., Rigby R.A., Heller G., Voudouris V., and De Bastiani F., (2017) Flexible Regression and Smoothing: Using GAMLSS in R, Chapman and Hall/CRC. doi:10.1201/b21973

Stasinopoulos, M. D., Rigby, R. A., and De Bastiani F., (2018) GAMLSS: a distributional regression approach, Statistical Modelling, Vol. 18, pp, 248-273, SAGE Publications Sage India: New Delhi, India.

Stasinopoulos, M.D., Kneib, T., Klein, N., Mayr, A. and Heller, G.Z., (2024). Generalized Additive Models for Location, Scale and Shape: A Distributional Regression Approach, with Applications (Vol. 56). Cambridge University Press.

(see also https://www.gamlss.com/).

Examples

# generating a t-distribution from 0 to 100  	
gen.trun(par=c(0,100),family="TF", extra.name="0to100", type="both")
op<-par(mfrow=c(2,2))
plot(function(x) dTF0to100(x, mu=80 ,sigma=20, nu=5), 0, 100, ylab="pdf")
plot(function(x) pTF0to100(x, mu=80 ,sigma=20, nu=5), 0, 100, ylab="cdf")
plot(function(x) qTF0to100(x, mu=80 ,sigma=20, nu=5), 0.01, .999, ylab="invcdf")
hist(s1<-rTF0to100(1000, mu=80 ,sigma=20, nu=5), ylab="hist", xlab="x", main="generated data")
par(op)

For fitting truncated distribution to the tails of data

Description

There are two functions here. The function fitTail() which fits a truncated distribution to certain percentage of the tail of a response variable and the function fitTailAll() which does a sequence of truncated fits. Plotting the results from those fits is analogous to the Hill plot, Hill (1975).

Usage

fitTail(y, family = "WEI3", percentage = 10, howmany = NULL, 
      type = c("right", "left"), ...)
   
fitTailAll(y, family = "WEI3", percentage = 10, howmany = NULL, 
      type = c("right", "left"), plot = TRUE, 
      print = TRUE, save = FALSE, start = 5, trace = 0,  ...)

Arguments

y

The variable of interest

family

a gamlsss.family distribution

percentage

what percentage of the tail need to be modelled, default is 10%

howmany

how many observations in the tail needed. This is an alternative to percentage. If it specified it take over from the percentage argument otherwise percentage is used.

type

which tall needs checking the right (default) of the left

plot

whether to plot with default equal TRUE

print

whether to print the coefficients with default equal TRUE

save

whether to save the fitted linear model with default equal FALSE

start

where to start fitting from the tail of the data

trace

0: no output 1: minimal 2: print estimates

...

for further argument to the fitting function

Details

The idea here is to fit a truncated distribution to the tail of the data. Truncated log-normal and Weibull distributions could be appropriate distributions. More details can be found in Chapter 6 of "The Distribution Toolbox of GAMLSS" book which can be found in https://www.gamlss.com/).

Value

A fitted gamlss model

Author(s)

Bob Rigby, Mikis Stasinopoulos and Vlassios Voudouris

References

Hill B. M. (1975) A Simple General Approach to Inference About the Tail of a Distribution Ann. Statist. Volume 3, Number 5, pp 1163-1174.

Rigby, R. A., Stasinopoulos, D. M., Heller, G. Z., and De Bastiani, F. (2019) Distributions for modeling location, scale, and shape: Using GAMLSS in R, Chapman and Hall/CRC. doi:10.1201/9780429298547 An older version can be found in https://www.gamlss.com/.

Stasinopoulos D. M. Rigby R.A. (2007) Generalized additive models for location scale and shape (GAMLSS) in R. Journal of Statistical Software, Vol. 23, Issue 7, Dec 2007, doi:10.18637/jss.v023.i07.

Stasinopoulos D. M., Rigby R.A., Heller G., Voudouris V., and De Bastiani F., (2017) Flexible Regression and Smoothing: Using GAMLSS in R, Chapman and Hall/CRC. doi:10.1201/b21973

Stasinopoulos, M. D., Rigby, R. A., and De Bastiani F., (2018) GAMLSS: a distributional regression approach, Statistical Modelling, Vol. 18, pp, 248-273, SAGE Publications Sage India: New Delhi, India.

Stasinopoulos, M.D., Kneib, T., Klein, N., Mayr, A. and Heller, G.Z., (2024). Generalized Additive Models for Location, Scale and Shape: A Distributional Regression Approach, with Applications (Vol. 56). Cambridge University Press.

(see also https://www.gamlss.com/).

See Also

loglogSurv, logSurv

Examples

data(film90)
F90 <- exp(film90$lborev1)# original scale
# trucated plots
# 10%
w403<- fitTail(F90, family=WEI3)
qqnorm(resid(w403))
abline(0,1, col="red")

## Not run: 
# hill -sequential plot 10
w1<-fitTailAll(F90)
# plot sigma
plot(w1[,2])
#-----------------
#LOGNO
l403<- fitTail(F90, family=LOGNO)
plot(l403)
qqnorm(resid(l403))
abline(0,1)
#  hill -sequential plot 10
l1<-fitTailAll(F90, family=LOGNO)
plot(l1[,2])
#-------------------------

## End(Not run)

Generates a truncated distribution from a gamlss.family

Description

The gen.trun() function allows the user to generate d, p, q, and r distribution functions plus an extra gamlss.family function for fitting a truncated distribution with gamlss.

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).

If the user want a different link (rather the default) for any of the parameters she/he has to declare at the generation of the functions, see example.

Usage

gen.trun(par = c(0), family = "NO", extra.name = "tr", 
         type = c("left", "right", "both"), 
         varying = FALSE,  print=TRUE, ...)

Arguments

par

a vector with one (for "left" or "right" truncation) or two elements for "both". When the argument varying = TRUE then par can be a vector or a matrix with two columns respectively.

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.

extra.name

the extra characters to be added to the name of new truncated distribution, by default it adds tr

type

whether "left", "right" or in "both" sides truncation is required

varying

whether the truncation varies for different observations. This can be useful in regression analysis. If varying = TRUE then par should be an n-length vector for type equal "left" and "right" and an n by 2 matrix for type="both"

print

whether to print the names of the created distribution

...

for extra arguments

Value

Returns the d, the p, the q, the r and the fitting functions of a truncated gamlss.family distribution.

Author(s)

Mikis Stasinopoulos [email protected] and Bob Rigby

References

Rigby, R. A., Stasinopoulos, D. M., Heller, G. Z., and De Bastiani, F. (2019) Distributions for modeling location, scale, and shape: Using GAMLSS in R, Chapman and Hall/CRC. doi:10.1201/9780429298547 An older version can be found in https://www.gamlss.com/.

Stasinopoulos D. M. Rigby R.A. (2007) Generalized additive models for location scale and shape (GAMLSS) in R. Journal of Statistical Software, Vol. 23, Issue 7, Dec 2007, doi:10.18637/jss.v023.i07.

Stasinopoulos D. M., Rigby R.A., Heller G., Voudouris V., and De Bastiani F., (2017) Flexible Regression and Smoothing: Using GAMLSS in R, Chapman and Hall/CRC. doi:10.1201/b21973

Stasinopoulos, M. D., Rigby, R. A., and De Bastiani F., (2018) GAMLSS: a distributional regression approach, Statistical Modelling, Vol. 18, pp, 248-273, SAGE Publications Sage India: New Delhi, India.

Stasinopoulos, M.D., Kneib, T., Klein, N., Mayr, A. and Heller, G.Z., (2024). Generalized Additive Models for Location, Scale and Shape: A Distributional Regression Approach, with Applications (Vol. 56). Cambridge University Press.

(see also https://www.gamlss.com/).

See Also

trun.d, trun.p, trun.q, trun.r

Examples

# generating a t-distribution from 0 to 100  	
gen.trun(par=c(0,100),family="TF", extra.name="0to100", type="both")
op<-par(mfrow=c(2,2))
plot(function(x) dTF0to100(x, mu=80 ,sigma=20, nu=5), 0, 100, ylab="pdf")
plot(function(x) pTF0to100(x, mu=80 ,sigma=20, nu=5), 0, 100, ylab="cdf")
plot(function(x) qTF0to100(x, mu=80 ,sigma=20, nu=5), 0.01, .999, ylab="invcdf")
hist(s1<-rTF0to100(1000, mu=80 ,sigma=20, nu=5), ylab="hist", xlab="x", 
            main="generated data")
par(op)
m1<-histDist(s1, family=TF0to100, xlim=c(0,100))# fitting the data
# using the argumnt varying 
# left part varies right part equal 100
leftPAR <- rPO(100)
gen.trun(par=cbind(leftPAR,rep(100, 100)),family="TF", 
             extra.name="0to100Varying", 
            type="both", varying=TRUE)
YY<- rTF0to100Varying(100, mu=80, sigma=20, nu=5)
m1<-gamlss(YY~1, family=TF0to100Varying)
m1

Fits a Truncate Distribution from a gamlss.family

Description

This function can be used to fit truncated distributions. It takes as an argument an existing GAMLSS family distribution and a parameter vector, of the type c(left.value, right.value), and generates a gamlss.family object which then can be used to fit a truncated distribution.

Usage

trun(par = c(0), family = "NO",  type = c("left", "right", "both"), 
       extra.name = "tr", local = TRUE, delta=NULL, varying = FALSE, ...)

Arguments

par

a vector with one (for "left" or "right" truncation) or two elements for "both". When the argument varying = TRUE then par can be a vector or a matrix with two columns respectively.

family

an existing gamlss.family distribution

type

what type of truncation is required, left, right or both. If both the par should be a vector of length two. (the default is left truncation)

extra.name

a character string to be added to name of the created object i.e. with family=TF and ext.name=trZero the gamlss.family object will be called TFtrZero

local

if TRUE the function will try to find the environment of gamlss to generate the d and p functions required for the fitting, if FALSE the functions will be generated in the global environment

delta

the default delta increment used in the numerical derivatives see notes below

varying

whether the truncation varies for diferent observations. This can be usefull in regression analysis. If varying = TRUE then par should be an n-length vector for type equal "left" and "right" and an n by 2 matrix for type="both"

...

for extra arguments

Details

This function is created to help the user to fit a truncated form of an existing gamlss distribution. It does this by taking an existing gamlss.family and changing some of the components of the distribution to help the fitting process. It particular it i) creates a pdf (d) and a cdf (p) function within gamlss, ii) changes the global deviance function G.dev.incr, the first derivative functions (see note below) and the quantile residual function.

Value

It returns a gamlss.family object which has all the components needed for fitting a distribution in gamlss.

Note

This function is experimental and could be changed. The function trun changes the first derivatives of the original gamlss family d function to numerical derivatives for the new truncated d function. The default increment delta, for this numerical derivatives function, is eps * pmax(abs(x), 1) where eps<-sqrt(.Machine$double.eps). The default delta could be inappropriate for specific applications and can be overwritten by using the argument delta.

Author(s)

Mikis Stasinopoulos [email protected] and Bob Rigby

References

Rigby, R. A., Stasinopoulos, D. M., Heller, G. Z., and De Bastiani, F. (2019) Distributions for modeling location, scale, and shape: Using GAMLSS in R, Chapman and Hall/CRC. doi:10.1201/9780429298547 An older version can be found in https://www.gamlss.com/.

Stasinopoulos D. M. Rigby R.A. (2007) Generalized additive models for location scale and shape (GAMLSS) in R. Journal of Statistical Software, Vol. 23, Issue 7, Dec 2007, doi:10.18637/jss.v023.i07.

Stasinopoulos D. M., Rigby R.A., Heller G., Voudouris V., and De Bastiani F., (2017) Flexible Regression and Smoothing: Using GAMLSS in R, Chapman and Hall/CRC. doi:10.1201/b21973

Stasinopoulos, M. D., Rigby, R. A., and De Bastiani F., (2018) GAMLSS: a distributional regression approach, Statistical Modelling, Vol. 18, pp, 248-273, SAGE Publications Sage India: New Delhi, India.

Stasinopoulos, M.D., Kneib, T., Klein, N., Mayr, A. and Heller, G.Z., (2024). Generalized Additive Models for Location, Scale and Shape: A Distributional Regression Approach, with Applications (Vol. 56). Cambridge University Press.

(see also https://www.gamlss.com/).

See Also

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

Examples

# generate a left truncated zero t family
gen.trun(0,family="TF")
# take a random sample of 1000 observations
sam<-rTFtr(1000,mu=10,sigma=5, nu=5 )
hist(sam)
# fit the distribution to the data
mod1<-gamlss(sam~1, family=trun(0,TF))
mod1
# now create a gamlss.family object before the fitting 
Ttruc.Zero<- trun(par=0,family=TF, local=FALSE)
mod2<-gamlss(sam~1, family=Ttruc.Zero)
# now check the sensitivity of delta 
Ttruc.Zero<- trun(par=0,family=TF, local=FALSE, delta=c(0.01,0.01, 0.01))
mod3<-gamlss(sam~1, family=Ttruc.Zero)

Truncated Probability Density Function of a gamlss.family Distribution

Description

Creates a truncated probability density function version 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.d(par, family = "NO", type = c("left", "right", "both"),
       varying = FALSE, ...)

Arguments

par

a vector with one (for "left" or "right" truncation) or two elements for "both". When the argument varying = TRUE then par can be a vector or a matrix with two columns respectively.

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).

varying

whether the truncation varies for diferent observations. This can be usefull in regression analysis. If varying = TRUE then par should be an n-length vector for type equal "left" and "right" and an n by 2 matrix for type="both"

...

for extra arguments

Value

Returns a d family function

Author(s)

Mikis Stasinopoulos [email protected] and Bob Rigby

References

Rigby, R. A., Stasinopoulos, D. M., Heller, G. Z., and De Bastiani, F. (2019) Distributions for modeling location, scale, and shape: Using GAMLSS in R, Chapman and Hall/CRC. doi:10.1201/9780429298547 An older version can be found in https://www.gamlss.com/.

Stasinopoulos D. M. Rigby R.A. (2007) Generalized additive models for location scale and shape (GAMLSS) in R. Journal of Statistical Software, Vol. 23, Issue 7, Dec 2007, doi:10.18637/jss.v023.i07.

Stasinopoulos D. M., Rigby R.A., Heller G., Voudouris V., and De Bastiani F., (2017) Flexible Regression and Smoothing: Using GAMLSS in R, Chapman and Hall/CRC. doi:10.1201/b21973

Stasinopoulos, M. D., Rigby, R. A., and De Bastiani F., (2018) GAMLSS: a distributional regression approach, Statistical Modelling, Vol. 18, pp, 248-273, SAGE Publications Sage India: New Delhi, India.

Stasinopoulos, M.D., Kneib, T., Klein, N., Mayr, A. and Heller, G.Z., (2024). Generalized Additive Models for Location, Scale and Shape: A Distributional Regression Approach, with Applications (Vol. 56). Cambridge University Press.

(see also https://www.gamlss.com/).

See Also

trun.p, trun.q, trun.r, gen.trun

Examples

#------------------------------------------------------------------------------------------
# continuous distribution 
# left truncation 
test1<-trun.d(par=c(0), family="TF", type="left")
test1(1)
dTF(1)/(1-pTF(0))
if(abs(test1(1)-(dTF(1)/pTF(0)))>0.00001) stop("error in left trucation")
test1(1, log=TRUE)
log(dTF(1)/(1-pTF(0)))
if(abs(test1(1, log=TRUE)-log(dTF(1)/pTF(0)))>0.00001) 
                   stop("error in left trucation")
integrate(function(x) test1(x, mu=-2, sigma=1, nu=1),0,Inf) 
# the pdf is defined even with negative mu
integrate(function(x) test1(x, mu=0, sigma=10, nu=1),0,Inf) 
integrate(function(x) test1(x, mu=5, sigma=5, nu=10),0,Inf)
plot(function(x) test1(x, mu=-3, sigma=1, nu=1),0,10)
plot(function(x) test1(x, mu=3, sigma=5, nu=10),0,10)
#----------------------------------------------------------------------------------------
# right truncation
test2<-trun.d(par=c(10), family="BCT", type="right")
test2(1)
dBCT(1)/(pBCT(10))
#if(abs(test2(1)-(dBCT(1)/pBCT(10)))>0.00001) stop("error in right trucation")
test2(1, log=TRUE)
log(dBCT(1)/(pBCT(10)))
if(abs(test2(1, log=TRUE)-log(dBCT(1)/(pBCT(10))))>0.00001) 
                   stop("error in right trucation")
integrate(function(x) test2(x, mu=2, sigma=1, nu=1),0,10) 
integrate(function(x) test2(x, mu=2, sigma=.1, nu=1),0,10) 
integrate(function(x) test2(x, mu=2, sigma=.1, nu=10),0,10) 
plot(function(x) test2(x, mu=2, sigma=.1, nu=1),0,10)
plot(function(x) test2(x, mu=2, sigma=1, nu=1),0,10)
#-----------------------------------------------------------------------------------------
# both left and right truncation
test3<-trun.d(par=c(-3,3), family="TF", type="both")
test3(0)
dTF(0)/(pTF(3)-pTF(-3))
if(abs(test3(0)-dTF(0)/(pTF(3)-pTF(-3)))>0.00001) 
              stop("error in right trucation")
test3(0, log=TRUE)
log(dTF(0)/(pTF(3)-pTF(-3)))
if(abs(test3(0, log=TRUE)-log(dTF(0)/(pTF(3)-pTF(-3))))>0.00001) 
            stop("error in both trucation")
plot(function(x) test3(x, mu=0, sigma=1, nu=1),-3,3)
integrate(function(x) test3(x, mu=2, sigma=1, nu=1),-3,3)
#-----------------------------------------------------------------------------------------
# discrete distribution
# left 
# Poisson truncated at zero means zero is excluded
test4<-trun.d(par=c(0), family="PO", type="left")
test4(1)
dPO(1)/(1-pPO(0))
if(abs(test4(1)-dPO(1)/(1-pPO(0)))>0.00001) stop("error in left trucation")
test4(1, log=TRUE)
log(dPO(1)/(1-pPO(0)))
if(abs(test4(1, log=TRUE)-log(dPO(1)/(1-pPO(0))))>0.00001) 
               stop("error in left trucation")
sum(test4(x=1:20, mu=2)) # 
sum(test4(x=1:200, mu=80)) #
plot(function(x) test4(x, mu=20), from=1, to=51, n=50+1, type="h") # pdf 
# right
# right truncated at 10 means 10 is excluded
test5<-trun.d(par=c(10), family="NBI", type="right")
test5(2)
dNBI(2)/(pNBI(9))
if(abs(test5(1)-dNBI(1)/(pNBI(9)))>0.00001) stop("error in right trucation")
test5(1, log=TRUE)
log(dNBI(1)/(pNBI(9)))
if(abs(test5(1, log=TRUE)-log(dNBI(1)/(pNBI(9))))>0.00001) stop("error in right trucation")
sum(test5(x=0:9, mu=2,   sigma=2)) # 
sum(test5(x=0:9, mu=300, sigma=5)) # can have mu > parameter
plot(function(x) test5(x, mu=20, sigma=3), from=0, to=9, n=10, type="h") # pdf
plot(function(x) test5(x, mu=300, sigma=5), from=0, to=9, n=10, type="h") # pdf
#----------------------------------------------------------------------------------------
# both
test6<-trun.d(par=c(0,10), family="NBI", type="both")
test6(2)
dNBI(2)/(pNBI(9)-pNBI(0))
if(abs(test6(2)-dNBI(2)/(pNBI(9)-pNBI(0)))>0.00001) 
        stop("error in right trucation")
test6(1, log=TRUE)
log(dNBI(1)/(pNBI(9)-pNBI(0)))
if(abs(test6(1, log=TRUE)-log(dNBI(1)/(pNBI(9)-pNBI(0))))>0.00001) 
  stop("error in right trucation")
sum(test6(x=1:9, mu=2,   sigma=2)) # 
sum(test6(x=1:9, mu=100, sigma=5)) # can have mu > parameter
plot(function(x) test6(x, mu=20, sigma=3), from=1, to=9, n=9, type="h") # pdf
plot(function(x) test6(x, mu=300, sigma=.4), from=1, to=9, n=9, type="h") # pdf
#------------------------------------------------------------------------------------------
# now try when the trucated points varies for each observarion
# this will be appropriate for regression models only 
# continuous
#----------------------------------------------------------------------------------------
# left truncation
test7<-trun.d(par=c(0,1,2), family="TF", type="left", varying=TRUE)
test7(c(1,2,3))
dTF(c(1,2,3))/(1-pTF(c(0,1,2)))
test7(c(1,2,3), log=TRUE)
#----------------------------------------------------------------------------------------
# right truncation
test8<-trun.d(par=c(10,11,12), family="BCT", type="right", varying=TRUE)
test8(c(1,2,3))
dBCT(c(1,2,3))/(pBCT(c(10,11,12)))
test8(c(1,2,3), log=TRUE)
#----------------------------------------------------------------------------------------
# both left and right truncation
test9<-trun.d(par=cbind(c(0,1,2),c(10,11,12) ), family="TF", type="both", 
             varying=TRUE)
test9(c(1,2,3))
dTF(c(1,2,3))/ (pTF(c(10,11,12))-pTF(c(0,1,2)))
test3(c(1,2,3), log=TRUE)
#----------------------------------------------------------------------------------------
# discrete
# left
test10<-trun.d(par=c(0,1,2), family="PO", type="left", varying=TRUE)
test10(c(1,2,3))
dPO(c(1,2,3))/(1-pPO(c(0,1,2)))
# right
test11<-trun.d(par=c(10,11,12), family="NBI", type="right", varying=TRUE)
test11(c(1,2,3))
dNBI(c(1,2,3))/pNBI(c(9,10,11))
# both
test12<-trun.d(par=rbind(c(0,10), c(1,11), c(2,12)), family="NBI", type="both", varying=TRUE)
test12(c(2,3,4))
dNBI(c(2,3,4))/(pNBI(c(9,10,11))-pNBI(c(0,1,2)))

Truncated Cumulative Density Function of a gamlss.family Distribution

Description

Creates a truncated cumulative density function version 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.p(par, family = "NO", type = c("left", "right", "both"),
        varying = FALSE, ...)

Arguments

par

a vector with one (for "left" or "right" truncation) or two elements for "both". When the argument varying = TRUE then par can be a vector or a matrix with two columns respectively.

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)

varying

whether the truncation varies for diferent observations. This can be usefull in regression analysis. If varying = TRUE then par should be an n-length vector for type equal "left" and "right" and an n by 2 matrix for type="both"

...

for extra arguments

Value

Return a p family function

Author(s)

Mikis Stasinopoulos [email protected] and Bob Rigby

References

Rigby, R. A., Stasinopoulos, D. M., Heller, G. Z., and De Bastiani, F. (2019) Distributions for modeling location, scale, and shape: Using GAMLSS in R, Chapman and Hall/CRC. doi:10.1201/9780429298547 An older version can be found in https://www.gamlss.com/.

Stasinopoulos D. M. Rigby R.A. (2007) Generalized additive models for location scale and shape (GAMLSS) in R. Journal of Statistical Software, Vol. 23, Issue 7, Dec 2007, doi:10.18637/jss.v023.i07.

Stasinopoulos D. M., Rigby R.A., Heller G., Voudouris V., and De Bastiani F., (2017) Flexible Regression and Smoothing: Using GAMLSS in R, Chapman and Hall/CRC. doi:10.1201/b21973

Stasinopoulos, M. D., Rigby, R. A., and De Bastiani F., (2018) GAMLSS: a distributional regression approach, Statistical Modelling, Vol. 18, pp, 248-273, SAGE Publications Sage India: New Delhi, India.

Stasinopoulos, M.D., Kneib, T., Klein, N., Mayr, A. and Heller, G.Z., (2024). Generalized Additive Models for Location, Scale and Shape: A Distributional Regression Approach, with Applications (Vol. 56). Cambridge University Press.

(see also https://www.gamlss.com/).

See Also

trun.d, trun.q, trun.r, gen.trun

Examples

# trucated p  continuous function
# continuous
#----------------------------------------------------------------------------------------
# left
test1<-trun.p(par=c(0), family="TF", type="left")
test1(1)
(pTF(1)-pTF(0))/(1-pTF(0))
if(abs(test1(1)-(pTF(1)-pTF(0))/(1-pTF(0)))>0.00001) 
                      stop("error in left trucation of p")
plot(function(x) test1(x, mu=2, sigma=1, nu=2),0,10)
#----------------------------------------------------------------------------------------
# right
test2 <- trun.p(par=c(10), family="BCT", type="right")
test2(1)
pBCT(1)/pBCT(10)
if(abs(test2(1)-pBCT(1)/pBCT(10))>0.00001) stop("error in right trucation")
test2(1, lower.tail=FALSE)
1-pBCT(1)/pBCT(10)
if(abs(test2(1, lower.tail=FALSE)-(1-pBCT(1)/pBCT(10)))>0.00001) 
                stop("error in right trucation")
test2(1, log.p=TRUE)
log(pBCT(1)/pBCT(10))
if(abs(test2(1, log.p=TRUE)-log(pBCT(1)/pBCT(10)))>0.00001) 
               stop("error in right trucation")
plot(function(x) test2(x, mu=2, sigma=1, nu=2, tau=2),0,10)
plot(function(x) test2(x, mu=2, sigma=1, nu=2, tau=2, 
                       lower.tail=FALSE),0,10)
#----------------------------------------------------------------------------------------
# both 
test3<-trun.p(par=c(-3,3), family="TF", type="both")
test3(1)
(pTF(1)-pTF(-3))/(pTF(3)-pTF(-3))
if(abs(test3(1)-(pTF(1)-pTF(-3))/(pTF(3)-pTF(-3)))>0.00001) 
             stop("error in right trucation")
test3(1, lower.tail=FALSE)
1-(pTF(1)-pTF(-3))/(pTF(3)-pTF(-3))
if(abs(test3(0,lower.tail=FALSE)-
            (1-(pTF(0)-pTF(-3))/(pTF(3)-pTF(-3))))>0.00001) 
      stop("error in right trucation")
plot(function(x) test3(x, mu=2, sigma=1, nu=2, ),-3,3)
plot(function(x) test3(x, mu=2, sigma=1, nu=2, lower.tail=FALSE),-3,3)
#----------------------------------------------------------------------------------------
# Discrete
#----------------------------------------------------------------------------------------
# trucated p function
# left
test4<-trun.p(par=c(0), family="PO", type="left")
test4(1)
(pPO(1)-pPO(0))/(1-pPO(0))
if(abs(test4(1)-(pPO(1)-pPO(0))/(1-pPO(0)))>0.00001) 
               stop("error in left trucation of p")
plot(function(x) test4(x, mu=2), from=1, to=10, n=10, type="h")
cdf <- stepfun(1:40, test4(1:41, mu=5), f = 0)
plot(cdf, main="cdf", ylab="cdf(x)", do.points=FALSE )
#----------------------------------------------------------------------------------------
# right
test5<-trun.p(par=c(10), family="NBI", type="right")
test5(2)
pNBI(2)/(pNBI(9))
if(abs(test5(2)-(pNBI(2)/(pNBI(9))))>0.00001) 
          stop("error in right trucation of p")
plot(function(x) test5(x, mu=2), from=0, to=9, n=10, type="h")
cdf <- stepfun(0:8, test5(0:9, mu=5), f = 0)
plot(cdf, main="cdf", ylab="cdf(x)", do.points=FALSE )
#----------------------------------------------------------------------------------------
# both 
test6<-trun.p(par=c(0,10), family="NBI", type="both")
test6(2)
(pNBI(2)-pNBI(0))/(pNBI(9)-pNBI(0))
if(abs(test6(2)-(pNBI(2)-pNBI(0))/(pNBI(9)-pNBI(0)))>0.00001) 
               stop("error in the both trucation")
test6(1, log=TRUE)
log((pNBI(1)-pNBI(0))/(pNBI(9)-pNBI(0)))
if(abs(test6(1, log=TRUE)-log((pNBI(1)-pNBI(0))/(pNBI(9)-pNBI(0))))>0.00001) 
             stop("error in both trucation")
plot(function(y) test6(y, mu=20, sigma=3), from=1, to=9, n=9, type="h") 
plot(function(y) test6(y, mu=300, sigma=.4), from=1, to=9, n=9, type="h")
cdf <- stepfun(1:8, test6(1:9, mu=5), f = 0)
plot(cdf, main="cdf", ylab="cdf(x)", do.points=FALSE )
#----------------------------------------------------------------------------------------
# varying  truncation
#----------------------------------------------------------------------------------------
# coninuous
# left
test6<-trun.p(par=c(0,1,2), family="TF", type="left", varying=TRUE)
test6(c(2,3,4))
(pTF(c(2,3,4))-pTF(c(0,1,2)))/(1-pTF(c(0,1,2)))
test6(c(2,3,4), log.p=TRUE)
#----------------------------------------------------------------------------------------
# right
test7 <- trun.p(par=c(10,11,12), family="BCT", type="right", varying=TRUE)
test7(c(1,2,3))
pBCT(c(1,2,3))/pBCT(c(10,11,12))
test7(c(1,2,3), lower.tail=FALSE)
1-pBCT(c(1,2,3))/pBCT(c(10,11,12))
test7(c(1,2,3), log.p=TRUE)
#--------------------------------------------------------------------------------------- 
# both 
test8<-trun.p(par=cbind(c(0,1,2), c(10,11,12)), family="TF", 
           type="both", varying=TRUE)
test8(c(1,2,3))
(pTF(c(1,2,3))-pTF(c(0,1,2)))/(pTF(c(10,11,12))-pTF(c(0,1,2)))
test8(c(1,2,3), lower.tail=FALSE)
1-(pTF(c(1,2,3))-pTF(c(0,1,2)))/(pTF(c(10,11,12))-pTF(c(0,1,2)))
#--------------------------------------------------------------------------------------
# discrete
#--------------------------------------------------------------------------------------
# left
test9<-trun.p(par=c(0,1,2), family="PO", type="left", varying=TRUE)
test9(c(1,2,3))
(pPO(c(1,2,3))-pPO(c(0,1,2)))/(1-pPO(c(0,1,2)))
#--------------------------------------------------------------------------------------
# right
test10<-trun.p(par=c(10,11,12), family="NBI", type="right", varying=TRUE)
test10(c(2,3,4))
pNBI(c(2,3,4))/(pNBI(c(9,10,11)))
#-------------------------------------------------------------------------------------
# both
test11<-trun.p(par=rbind(c(0,10), c(1,11), c(2, 12)), family="NBI", 
              type="both", varying=TRUE)
test11(c(2,3,4))
(pNBI(c(2,3,4))-pNBI(c(0,1,2)))/(pNBI(c(9,10,11))-pNBI(c(0,1,2)))
#-------------------------------------------------------------------------------------

Truncated Inverse Cumulative Density Function of a gamlss.family Distribution

Description

Creates a function to produce the inverse of a truncated cumulative density function generated 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.q(par, family = "NO", type = c("left", "right", "both"),
        varying = FALSE, ...)

Arguments

par

a vector with one (for "left" or "right" truncation) or two elements for "both". When the argument varying = TRUE then par can be a vector or a matrix with two columns respectively.

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)

varying

whether the truncation varies for diferent observations. This can be usefull in regression analysis. If varying = TRUE then par should be an n-length vector for type equal "left" and "right" and an n by 2 matrix for type="both"

...

for extra arguments

Value

Returns a q family function

Author(s)

Mikis Stasinopoulos [email protected] and Bob Rigby

References

Rigby, R. A., Stasinopoulos, D. M., Heller, G. Z., and De Bastiani, F. (2019) Distributions for modeling location, scale, and shape: Using GAMLSS in R, Chapman and Hall/CRC. doi:10.1201/9780429298547 An older version can be found in https://www.gamlss.com/.

Stasinopoulos D. M. Rigby R.A. (2007) Generalized additive models for location scale and shape (GAMLSS) in R. Journal of Statistical Software, Vol. 23, Issue 7, Dec 2007, doi:10.18637/jss.v023.i07.

Stasinopoulos D. M., Rigby R.A., Heller G., Voudouris V., and De Bastiani F., (2017) Flexible Regression and Smoothing: Using GAMLSS in R, Chapman and Hall/CRC. doi:10.1201/b21973

Stasinopoulos, M. D., Rigby, R. A., and De Bastiani F., (2018) GAMLSS: a distributional regression approach, Statistical Modelling, Vol. 18, pp, 248-273, SAGE Publications Sage India: New Delhi, India.

Stasinopoulos, M.D., Kneib, T., Klein, N., Mayr, A. and Heller, G.Z., (2024). Generalized Additive Models for Location, Scale and Shape: A Distributional Regression Approach, with Applications (Vol. 56). Cambridge University Press.

(see also https://www.gamlss.com/).

See Also

trun.d, trun.q, trun.r, gen.trun

Examples

# trucated q  continuous function
# continuous
#----------------------------------------------------------------------------------------
# left
test1<-trun.q(par=c(0), family="TF", type="left")
test1(.6)
qTF(pTF(0)+0.6*(1-pTF(0)))
#----------------------------------------------------------------------------------------
# right
test2 <- trun.q(par=c(10), family="BCT", type="right")
test2(.6)
qBCT(0.6*pBCT(10))
#----------------------------------------------------------------------------------------
# both
test3<-trun.q(par=c(-3,3), family="TF", type="both")
test3(.6)
qTF(0.6*(pTF(3)-pTF(-3))+pTF(-3))
#----------------------------------------------------------------------------------------
# varying  par
#----------------------------------------------------------------------------------------
# left
test7<-trun.q(par=c(0,1,2), family="TF", type="left", varying=TRUE)
test7(c(.5,.5,.6))
qTF(pTF(c(0,1,2))+c(.5,.5,.6)*(1-pTF(c(0,1,2))))
#---------------------------------------------------------------------------------------
# right
test9 <- trun.q(par=c(10,11,12), family="BCT", type="right", varying=TRUE)
test9(c(.5,.5,.6))
qBCT(c(.5,.5,.6)*pBCT(c(10,11,12)))
#----------------------------------------------------------------------------------------
# both
test10<-trun.q(par=cbind(c(0,1,2), c(10,11,12)), family="TF", type="both", varying=TRUE)
test10(c(.5, .5, .7))
qTF(c(.5, .5, .7)*(pTF(c(10,11,12))-pTF(c(0,1,2)))+pTF(c(0,1,2)))
#----------------------------------------------------------------------------------------
# FOR DISCRETE DISTRIBUTIONS
# trucated q function
# left
test4<-trun.q(par=c(0), family="PO", type="left")
test4(.6)
qPO(pPO(0)+0.6*(1-pPO(0)))
# varying
test41<-trun.q(par=c(0,1,2), family="PO", type="left", varying=TRUE)
test41(c(.6,.4,.5))
qPO(pPO(c(0,1,2))+c(.6,.4,.5)*(1-pPO(c(0,1,2))))
#----------------------------------------------------------------------------------------
# right
test5 <- trun.q(par=c(10), family="NBI", type="right")
test5(.6)
qNBI(0.6*pNBI(10))
test5(.6, mu=10, sigma=2)
qNBI(0.6*pNBI(10, mu=10, sigma=2), mu=10, sigma=2)
# varying
test51 <- trun.q(par=c(10, 11, 12), family="NBI", type="right", varying=TRUE)
test51(c(.6,.4,.5))
qNBI(c(.6,.4,.5)*pNBI(c(10, 11, 12)))
test51(c(.6,.4,.5), mu=10, sigma=2)
qNBI(c(.6,.4,.5)*pNBI(c(10, 11, 12), mu=10, sigma=2), mu=10, sigma=2)
#----------------------------------------------------------------------------------------
# both
test6<-trun.q(par=c(0,10), family="NBI", type="both")
test6(.6)
qNBI(0.6*(pNBI(10)-pNBI(0))+pNBI(0))
# varying 
test61<-trun.q(par=cbind(c(0,1,2), c(10,11,12)), family="NBI", type="both", varying=TRUE)
test61(c(.6,.4,.5))
qNBI(c(.6,.4,.5)*(pNBI(c(10,11,12))-pNBI(c(0,1,2)))+pNBI(c(0,1,2)))
#----------------------------------------------------------------------------------------

Generates Random Values from a Truncated Density Function of a gamlss.family Distribution

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"), 
          varying = FALSE, ...)

Arguments

par

a vector with one (for "left" or "right" truncation) or two elements for "both". When the argument varying = TRUE then par can be a vector or a matrix with two columns respectively.

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)

varying

whether the truncation varies for diferent observations. This can be usefull in regression analysis. If varying = TRUE then par should be an n-length vector for type equal "left" and "right" and an n by 2 matrix for type="both"

...

for extra arguments

Value

Returns a r family function

Author(s)

Mikis Stasinopoulos [email protected] and Bob Rigby

References

Rigby, R. A., Stasinopoulos, D. M., Heller, G. Z., and De Bastiani, F. (2019) Distributions for modeling location, scale, and shape: Using GAMLSS in R, Chapman and Hall/CRC. doi:10.1201/9780429298547 An older version can be found in https://www.gamlss.com/.

Stasinopoulos D. M. Rigby R.A. (2007) Generalized additive models for location scale and shape (GAMLSS) in R. Journal of Statistical Software, Vol. 23, Issue 7, Dec 2007, doi:10.18637/jss.v023.i07.

Stasinopoulos D. M., Rigby R.A., Heller G., Voudouris V., and De Bastiani F., (2017) Flexible Regression and Smoothing: Using GAMLSS in R, Chapman and Hall/CRC. doi:10.1201/b21973

Stasinopoulos, M. D., Rigby, R. A., and De Bastiani F., (2018) GAMLSS: a distributional regression approach, Statistical Modelling, Vol. 18, pp, 248-273, SAGE Publications Sage India: New Delhi, India.

Stasinopoulos, M.D., Kneib, T., Klein, N., Mayr, A. and Heller, G.Z., (2024). Generalized Additive Models for Location, Scale and Shape: A Distributional Regression Approach, with Applications (Vol. 56). Cambridge University Press.

(see also https://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
test4<-trun.r(par=c(0), family="PO", type="left")
tN <- table(Ni <- test4(1000))
r <- barplot(tN, col='lightblue')
#----------------------------------------------------------------------------------------
# right
test5 <- trun.r(par=c(10), family="NBI", type="right")
tN <- table(Ni <- test5(1000))
r <- barplot(tN, col='lightblue')
tN <- table(Ni <- test5(1000,mu=5))
r <- barplot(tN, col='lightblue')
tN <- table(Ni <- test5(1000,mu=10, sigma=.1))
r <- barplot(tN, col='lightblue')
#----------------------------------------------------------------------------------------
# both 
test6<-trun.r(par=c(0,10), family="NBI", type="both")
tN <- table(Ni <- test6(1000,mu=5))
r <- barplot(tN, col='lightblue')
#----------------------------------------------------------------------------------------
# varying = TRUE
#----------------------------------------------------------------------------------------
# continuous
#----------------------------------------------------------------------------------------
# left
test7<-trun.r(par=c(0,1,2), family="TF", type="left", varying=TRUE)
test7(3)

#----------------------------------------------------------------------------------------
# right
test8 <- trun.r(par=c(10,11,12), family="BCT", type="right", varying=TRUE)
test8(3)
#----------------------------------------------------------------------------------------
# both
test9<-trun.r(par=rbind(c(-3,3), c(-1,5), c(0,6)), , family="TF", type="both", varying=TRUE)
test9(3)
#----------------------------------------------------------------------------------------
# discrete 
# trucated r function
# left
test10<-trun.r(par=c(0,1,2), family="PO", type="left", varying=TRUE)
test10(3)
#----------------------------------------------------------------------------------------
# right
test11 <- trun.r(par=c(10,11,12), family="NBI", type="right", varying=TRUE)
test11(3)
test11(3, mu=10, sigma=.1)
#----------------------------------------------------------------------------------------
# both 
test12<-trun.r(par=rbind(c(0,10), c(1,11), c(2,12)), family="NBI", type="both", varying=TRUE)
test12(3,mu=5)