plotnpde {npde}R Documentation

Plots graphs of the normalised prediction distribution errors

Description

Plots 4 graphs to evaluate the shape of the distribution of the normalised prediction distribution errors (npde)

Usage

plotnpde(xobs, npde, ypred)

Arguments

xobs the vector of the observed independent variable (X)
npde the vector of normalised prediction distribution errors (returned by the functions npde or autonpde with the option output=TRUE)
ypred a vector giving the mean of the predicted distribution for each observation

Details

Four graphs are produced:

a quantile-quantile plot
plot of the npde versus the corresponding quantiles of a normal distribution, with the line y=x overlayed.
a histogram of the npde
the shape of the normal distribution is also shown
two scatterplots of the npde
a plot of the npde versus the independent variable X and a plot of the npde versus the empirical mean of the predicted distribution; for these last two graphs, we plot the lines corresponding to y=0 and to the 5 90

Value

None

Author(s)

Emmanuelle Comets <emmanuelle.comets@bichat.inserm.fr>

References

K. Brendel, E. Comets, C. Laffont, C. Laveille, and F. Mentré. Metrics for external model evaluation with an application to the population pharmacokinetics of gliclazide. Pharmaceutical Research, 23:2036–49, 2006.

See Also

npde, autonpde

Examples


#Computing npde
data(theopp)
data(simtheopp)

x<-autonpde(theopp,simtheopp,1,3,4,boolsave=FALSE)
x$npde

#Using the npde in object x for the plot
plotnpde(x$obsdat$xobs,x$npde,x$ypred)

[Package npde version 1.2 Index]