# hdr.boxplot: Highest Density Region Boxplots In robjhyndman/hdrcde: Highest Density Regions and Conditional Density Estimation

 hdr.boxplot R Documentation

## Highest Density Region Boxplots

### Description

Calculates and plots a univariate highest density regions boxplot.

### Usage

```hdr.boxplot(
x,
prob = c(99, 50),
h = hdrbw(BoxCox(x, lambda), mean(prob)),
lambda = 1,
boxlabels = "",
col = gray((9:1)/10),
main = "",
xlab = "",
ylab = "",
pch = 1,
border = 1,
outline = TRUE,
space = 0.25,
...
)
```

### Arguments

 `x` Numeric vector containing data or a list containing several vectors. `prob` Probability coverage required for HDRs `density`. `h` Optional bandwidth for calculation of density. `lambda` Box-Cox transformation parameter where ```0 <= lambda <= 1```. `boxlabels` Label for each box plotted. `col` Colours for regions of each box. `main` Overall title for the plot. `xlab` Label for x-axis. `ylab` Label for y-axis. `pch` Plotting character. `border` Width of border of box. `outline` If not TRUE, the outliers are not drawn. `space` The space between each box, between 0 and 0.5. `...` Other arguments passed to plot.

### Details

The density is estimated using kernel density estimation. A Box-Cox transformation is used if `lambda!=1`, as described in Wand, Marron and Ruppert (1991). This allows the density estimate to be non-zero only on the positive real line. The default kernel bandwidth `h` is selected using the algorithm of Samworth and Wand (2010).

Hyndman's (1996) density quantile algorithm is used for calculation.

nothing.

Rob J Hyndman

### References

Hyndman, R.J. (1996) Computing and graphing highest density regions. American Statistician, 50, 120-126.

Samworth, R.J. and Wand, M.P. (2010). Asymptotics and optimal bandwidth selection for highest density region estimation. The Annals of Statistics, 38, 1767-1792.

Wand, M.P., Marron, J S., Ruppert, D. (1991) Transformations in density estimation. Journal of the American Statistical Association, 86, 343-353.

`hdr.boxplot.2d`, `hdr`, `hdr.den`

### Examples

```# Old faithful eruption duration times
hdr.boxplot(faithful\$eruptions)

# Simple bimodal example
x <- c(rnorm(100,0,1), rnorm(100,5,1))
par(mfrow=c(1,2))
boxplot(x)
hdr.boxplot(x)

# Highly skewed example
x <- exp(rnorm(100,0,1))
par(mfrow=c(1,2))
boxplot(x)
hdr.boxplot(x,lambda=0)

```

robjhyndman/hdrcde documentation built on Aug. 18, 2022, 6:36 a.m.