# Mean residual life plot

### Description

Produce a mean residual life plot to aid the identification of a threshold over which to fit a generalized Pareto distribution

### Usage

1 |

### Arguments

`data` |
A numeric vector. |

`umin` |
The minimum value over which to threshold the data. |

`umax` |
The maximum value over which to threshold the data. |

`conf` |
The coverage of confidence interval to plot. Defaults to plotting a 95% interval. |

`nint` |
The number of points at which to compute the plot. |

`...` |
Optional arguments to |

### Details

Threshold choice for the fitting of the GPD is guided by the shape of the Mean Residual Life plot. A threshold which is suitably high will have a corresponding mrl plot which is approximately linear in shape above the threshold (up to sampling variation).

### Value

NULL

### Note

The function was originally written by Janet E. Heffernan and appears in
the `ismev`

package. This version modified by Harry Southworth to
allow more control over the appearance of the plot.

### Author(s)

Janet E. Heffernan, Harry Southworth

### References

S. Coles, An Introduction to Statistical Modeling of Extreme Values, Springer, 2001