npnorm: Class 'npnorm'

In nspmix: Nonparametric and Semiparametric Mixture Estimation

Description

Class npnorm can be used to store data that will be processed as those of a nonparametric normal mixture. There are several functions associated with the class.

Usage

npnorm(v, w=1)
rnpnorm(n, mix=disc(0), sd=1)
## S3 method for class 'npnorm'
plot(x, mix, beta, breaks=NULL, col="red", len=100,
    add=FALSE, border.col=NULL, border.lwd=1,
    fill="lightgrey", main, lwd=2, lty=1, xlab="Data",
    ylab="Density", components=c("proportions","curves","null"),
    lty.components=2, lwd.components=2, ...)

Arguments

v	a numeric vector that stores the values of a sample.
w	a numeric vector that stores the corresponding weights/frequencies of the observations.
n	the sample size.
mix	an object of class disc, for a discrete distribution.
beta	the structural parameter.
sd	a scalar for the component standard deviation that is common to all components.
x	an object of class npnorm.
breaks	the rough number bins used for plotting the histogram.
col	the color of the density curve to be plotted.
len	the number of points roughly used to plot the density curve over the interval of length 8 times the component standard deviation around each component mean.
add	if FALSE, creates a new plot; if TRUE, adds the plot to the existing one.
border.col	color for the border of histogram boxes.
border.lwd	line width for the border of histogram boxes.
fill	color to fill in the histogram boxes.
components	if proportions (default), also show the support points and mixing proportions; if curves, also show the component density curves; if null, components are not shown.
lty.components, lwd.components	line type and width for the component curves.
main, lwd, lty, xlab, ylab	arguments for graphical parameters (see par).
...	arguments passed on to function plot.

Details

Function npnorm creates an object of class npnorm, given values and weights/frequencies.

Function rnpnorm generates a random sample from a normal mixture and saves the data as an object of class npnorm.

Function plot.npnorm plots the normal mixture.

When components="proportions", the component means are shown on the horizontal line of density 0. The vertical lines going upwardly at the support points are proportional to the mixing proportions at these points.

Author(s)

Yong Wang <[e-mail]>

References

Wang, Y. (2007). On fast computation of the non-parametric maximum likelihood estimate of a mixing distribution. Journal of the Royal Statistical Society, Ser. B, 69, 185-198.

See Also

nnls, cnm, cnmms, plot.nspmix.

Examples

mix = disc(pt=c(0,4), pr=c(0.3,0.7))  # a discrete distribution
x = rnpnorm(200, mix, sd=1)
plot(x, mix, beta=1)

nspmix documentation built on Oct. 23, 2020, 6:46 p.m.