R: Functional bagplot and functional HDR boxplot

fboxplot {rainbow} | R Documentation

## Functional bagplot and functional HDR boxplot

### Description

Compute bivariate bagplot, functional bagplot and bivariate HDR boxplot, functional HDR boxplot.

### Usage

    fboxplot(data, plot.type = c("functional", "bivariate"),
    	type = c("bag", "hdr"), alpha = c(0.05, 0.5), projmethod = c("PCAproj","rapca"),
    	factor = 1.96, na.rm = TRUE, xlab = data$xname, ylab = data$yname,
    	shadecols = gray((9:1)/10), pointcol = 1, plotlegend = TRUE,
    	legendpos = "topright", ncol = 2, ...)

### Arguments

`data` | An object of class `fds` or `fts`.
`plot.type` | Version of boxplot. When `plot.type="functional"`, a functional plot is provided. When `plot.type="bivariate"`, a square bivariate plot is provided.
`type` | Type of boxplot. When `type = "bag"`, a bagplot is provided. When `type = "hdr"`, a HDR boxplot is provided.
`alpha` | Coverage probability for the functional HDR boxplot. alpha are the coverage percentages of the outliers and the central region.
`factor` | When `type = "bag"`, the outer region of a bagplot is the convex hull obtained by inflating the inner region by the bagplot factor.
`na.rm` | Remove missing values.
`xlab` | A title for the x axis.
`ylab` | A title for the y axis.
`shadecols` | Colors for shaded regions.
`pointcol` | Color for outliers and mode.
`plotlegend` | Add a legend to the graph.
`legendpos` | Legend position. By default, it is the top right corner.
`ncol` | Number of columns in the legend.
`projmethod` | Method used for projection.
`...` | Other arguments.

### Details

The functional curves are first projected into a finite dimensional subspace via functional principal component decomposition. For simiplicity, we choose the subspace as R^2. Based on Tukey (1974)'s halfspace bagplot and Hyndman (1996)'s HDR boxplot, we order each data point in R^2 by data depth and data density. Outliers are those that have either lowest depth (distance from the centre) or lowest density.

### Value

Function produces a graphical plot.

### Author(s)

Rob J Hyndman, Han Lin Shang. Please, report bugs and suggestions to hanlin.shang@anu.edu.au

### References

J. W. Tukey (1974) "Mathematics and the picturing of data", Proceedings of the International Congress of Mathematicians, 2, 523-532, Canadian Mathematical Congress, Montreal.

P. Rousseeuw, I. Ruts and J. Tukey (1999) "The bagplot: A bivariate boxplot", The American Statistician, 53(4), 382-387.

R. J. Hyndman (1996) "Computing and graphing highest density regions", The American Statistician, 50(2), 120-126.

R. J. Hyndman and H. L. Shang (2010) "Rainbow plots, bagplots, and boxplots for functional data", Journal of Computational and Graphical Statistics, 19(1), 29-45.

Y. Sun and M. G. Genton (2011) "Functional boxplots", Journal of Computational and Graphical Statistics, 20(2), 316-334.

Y. Sun and M. G. Genton (2012) "Adjusted functional boxplots for spatio-temporal data visualization and outlier detection", Environmetrics, 23, 54-64.

Y. Sun and M. G. Genton (2012) "Functional median polish", Journal of Agricultural, Biological, and Environmental Statistics, 17, 354-376.

### See Also

`SVDplot`

### Examples

    fboxplot(data = ElNino, plot.type = "functional", type = "bag", projmethod="PCAproj")
    fboxplot(data = ElNino, plot.type = "bivariate", type = "bag", projmethod="PCAproj")

[Package rainbow version 3.5 Index]