R: Bivariate Threshold Choice Plot

bvtcplot {evd} | R Documentation

## Bivariate Threshold Choice Plot

### Description

Produces a diagnostic plot to assist with threshold choice for bivariate data.

### Usage

    bvtcplot(x, spectral = FALSE, xlab, ylab, ...)

### Arguments

`x` | A matrix or data frame, ordinarily with two columns, which may contain missing values.
`spectral` | If `TRUE`, an estimate of the spectral measure is plotted instead of the diagnostic plot.
`ylab, xlab` | Graphics parameters.
`...` | Other arguments to be passed to the plotting function.

### Details

If `spectral` is `FALSE` (the default), produces a threshold choice plot as illustrated in Beirlant et al. (2004). With n non-missing bivariate observations, the integers k = 1,...,n-1 are plotted against the values (k/n)r_(n-k), where r_(n-k) is the (n-k)th order statistic of the sum of the margins following empirical transformation to standard Frechet.

A vertical line is drawn at `k0`, where `k0` is the largest integer for which the y-axis is above the value two. If `spectral` is `FALSE`, the largest `k0` data points are used to plot an estimate of the spectal measure H([0, w]) versus w.

### Value

A list is invisibly returned giving `k0` and the values used to produce the plot.

### References

Beirlant, J., Goegebeur, Y., Segers, J. and Teugels, J. L. (2004) Statistics of Extremes: Theory and Applications., Chichester, England: John Wiley and Sons.

### See Also

`fbvpot`, `tcplot`

### Examples

    ## Not run: bvtcplot(lossalae)
    ## Not run: bvtcplot(lossalae, spectral = TRUE)

[Package evd version 2.3-5 Index]