Compute and display a univariate averaged shifted histogram (polynomial kernel)
Description
See bin1
& ash1
for more information.
Usage
1 2 3 
Arguments
mapping 
Set of aesthetic mappings created by 
data 
A data frame. If specified, overrides the default data frame defined at the top level of the plot. 
geom 
Use to override the default Geom 
position 
Position adjustment, either as a string, or the result of a call to a position adjustment function. 
ab 
halfopen interval for bins [a,b). If no value is specified,
the range of x is stretched by 
nbin 
number of bins desired. Default 
m 
integer smoothing parameter; Default 
kopt 
vector of length 2 specifying the kernel, which is proportional to ( 1  abs(i/m)^kopt(1) )i^kopt(2); (2,2)=biweight (default); (0,0)=uniform; (1,0)=triangle; (2,1)=Epanechnikov; (2,3)=triweight. 
na.rm 
If 
show.legend 
logical. Should this layer be included in the legends?

inherit.aes 
If 
... 
other arguments passed on to

Details
A sample of the output from stat_ash()
:
Aesthetics
geom_ash
understands the following aesthetics (required aesthetics
are in bold):

x

alpha

color

fill

linetype

size
Computed variables
density
ash density estimate
References
David Scott (1992), "Multivariate Density Estimation,"
John Wiley, (chapter 5 in particular).
B. W. Silverman (1986), "Density Estimation for Statistics
and Data Analysis," Chapman & Hall.
Examples
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20  # compare
library(gridExtra)
set.seed(1492)
dat < data.frame(x=rnorm(100))
grid.arrange(ggplot(dat, aes(x)) + stat_ash(),
ggplot(dat, aes(x)) + stat_bkde(),
ggplot(dat, aes(x)) + stat_density(),
nrow=3)
cols < RColorBrewer::brewer.pal(3, "Dark2")
ggplot(dat, aes(x)) +
stat_ash(alpha=1/2, fill=cols[3]) +
stat_bkde(alpha=1/2, fill=cols[2]) +
stat_density(alpha=1/2, fill=cols[1]) +
geom_rug() +
labs(x=NULL, y="density/estimate") +
scale_x_continuous(expand=c(0,0)) +
theme_bw() +
theme(panel.grid=element_blank()) +
theme(panel.border=element_blank())
