centiles.com: Comparing centiles from different GAMLSS models

Description Usage Arguments Value Warning Author(s) References See Also Examples

View source: R/centilescom.R

Description

This function compares centiles curves for more than one GAMLSS objects.It is based on the centiles function. The function also tabulates the sample percentages below each centile curve (for comparison with the model percentages given by the argument cent.) A restriction of the function is that it applies to models with one explanatory variable only

Usage

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centiles.com(obj, ..., xvar, cent = c(0.4, 10, 50, 90, 99.6), 
             legend = TRUE, ylab = "y", xlab = "x", xleg = min(xvar), 
             yleg = max(obj$y), xlim = range(xvar), ylim = NULL, 
             no.data = FALSE, color = TRUE, main = NULL, plot = TRUE)

Arguments

obj

a fitted gamlss object from fitting a gamlss continuous distribution

...

optionally more fitted GAMLSS model objects

xvar

the unique explanatory variable

cent

a vector with elements the % centile values for which the centile curves have to be evaluated

legend

whether a legend is required in the plot or not, the default is legent=TRUE

ylab

the y-variable label

xlab

the x-variable label

xleg

position of the legend in the x-axis

yleg

position of the legend in the y-axis

xlim

the limits of the x-axis

ylim

the limits of the y-axis

no.data

whether the data should plotted, default no.data=FALSE or not no.data=TRUE

color

whether the fitted centiles are shown in colour, color=TRUE (the default) or not color=FALSE

main

the main title

plot

whether to plot the centiles

Value

Centile plots are produced for the different fitted models and the sample centiles below each centile curve are printed

Warning

This function is appropriate only when one continuous explanatory variable is fitted in the model

Author(s)

Mikis Stasinopoulos d.stasinopoulos@londonmet.ac.uk and Bob Rigby r.rigby@londonmet.ac.uk

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.

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. 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, https://www.jstatsoft.org/v23/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.

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

See Also

gamlss, centiles , centiles.split

Examples

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data(abdom)
h1<-gamlss(y~cs(x,df=3), sigma.formula=~cs(x,1),family=BCT, data=abdom)
h2<-gamlss(y~pb(x), sigma.formula=~pb(x), family=BCT, data=abdom )
centiles.com(h1,h2,xvar=abdom$x)
rm(h1,h2)

Example output

Loading required package: splines
Loading required package: gamlss.data
Loading required package: gamlss.dist
Loading required package: MASS
Loading required package: nlme
Loading required package: parallel
 **********   GAMLSS Version 5.0-2  ********** 
For more on GAMLSS look at http://www.gamlss.org/
Type gamlssNews() to see new features/changes/bug fixes.

GAMLSS-RS iteration 1: Global Deviance = 4776.096 
GAMLSS-RS iteration 2: Global Deviance = 4775.896 
GAMLSS-RS iteration 3: Global Deviance = 4775.875 
GAMLSS-RS iteration 4: Global Deviance = 4775.876 
GAMLSS-RS iteration 1: Global Deviance = 4771.925 
GAMLSS-RS iteration 2: Global Deviance = 4771.039 
GAMLSS-RS iteration 3: Global Deviance = 4770.999 
GAMLSS-RS iteration 4: Global Deviance = 4770.994 
GAMLSS-RS iteration 5: Global Deviance = 4770.993 
********  Model 1 ******** 
% of cases below  0.4 centile is  0.6557377 
% of cases below  10 centile is  8.688525 
% of cases below  50 centile is  50.32787 
% of cases below  90 centile is  88.68852 
% of cases below  99.6 centile is  99.67213 
********  Model 2 ******** 
% of cases below  0.4 centile is  0.3278689 
% of cases below  10 centile is  8.688525 
% of cases below  50 centile is  50.16393 
% of cases below  90 centile is  90 
% of cases below  99.6 centile is  99.67213 

gamlss documentation built on March 31, 2021, 5:10 p.m.