fitted_centiles: Plotting centile (growth) curves

In gamlss.ggplots: Plotting Generalised Additive Model for Location, Scale and Shape

Plotting centile (growth) curves

Description

The function fitted_centiles() plots centiles curves for distributions belonging to the GAMLSS family of distributions. The plot is equivalent to the standard plot of gamlss:::centiles() without a legend.

The function fitted_centiles_legend() plots centiles curves for distributions belonging to the GAMLSS family of distributions and it is equivalent to the standard plot of gamlss:::centiles() with a legend. The function is slower than fitted_centiles() since in order to plot the legend the data have to expanded.

The function model_centiles() plots centile curves for more than one model. There is no equivalent plot in the original GAMLSS centile plots but it perform the same function as gamlss:::centiles.com() which compares centiles from different models.

Usage

fitted_centiles(obj, xvar, 
               cent = c(99.4, 98, 90, 75, 50, 25, 10, 2, 0.4), 
               points = TRUE, point.col = "gray", 
               point.size = 1, line.size = 0.8, 
               line.col = hcl.colors(lc, palette = "Dark 2"), 
               line.type = rep(1, length(cent)),
               xlab = NULL, ylab = NULL, title, ...)
               
fitted_centiles_legend(obj, xvar, 
               cent = c(99.4, 98, 90, 75, 50, 25, 10, 2, 0.4),   
               points = TRUE, point.col = "gray", point.size = 1, 
               line.size = 0.8, line.col = hcl.colors(ncent, 
               palette = "Dark 2"), line.type = rep(1, length(cent)),               
               show.legend = TRUE, save.data = FALSE, title, 
               xlab = NULL, ylab = NULL, ...)               

model_centiles(obj, ..., cent = c(97, 90, 75, 50, 25, 10, 3), 
               xvar, xlab = "age", points = TRUE, 
               point.col = gray(0.8), 
               point.size = 0.05, line.size = 0.7, 
               line.col = hcl.colors(ncent,palette = "Dark 2"), 
               ncol = 2, nrow = ceiling(nnames/ncol),  in.one = FALSE,
               title)               

Arguments

obj	a fitted gamlss object
xvar	the (unique) explanatory variable
cent	a vector with elements the % centile values for which the centile curves have to be evaluated (note that the order is from the highest to the lowest so legend and the plots are maching)
points	whether to plot the points (TRUE) of the data or not (FALSE)
point.col	the colour of the points
point.size	the zize of the points
line.size	the sized of the centile lines
line.col	the colour of the centile lines
line.type	the type of line (different types of lines for each centile are working with fitted_centiles_legend)
xlab	the label of the x-axis variable
ylab	the label of the resposnse variable
in.one	whether the model_centile plot should be one or multiple
title	the title if need it otherwise a dfault title is pronted
show.legend	whether to show the legend
save.data	whether to save the data.frame of the plot
nrow	the number of rows in the model_centiles() plot
ncol	the number of columns in the model_centiles() plot
...	for extra arguments for fitted_centiles(), and fitted_centiles.legend() and extra models for model_centiles()

Details

Centiles are calculated using the fitted values in obj and xvar must correspond exactly to the predictor in obj to plot correctly.

Value

A plot is created

Warning

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

Author(s)

Mikis Stasinopoulos, Bob Rigby and Fernanda de Bastiani

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

centiles

Examples

data(abdom)
h<-gamlss(y~pb(x), sigma.formula=~pb(x), family=BCTo, data=abdom) 
h1 <- gamlss(y~pb(x), sigma.formula=~pb(x), family=LO, data=abdom) 
fitted_centiles(h)
fitted_centiles_legend(h)
model_centiles(h, h1)

gamlss.ggplots documentation built on Sept. 3, 2023, 5:08 p.m.