# [R] Peak Over Threshold values/ length of the events

Tonja Krueger tonja.krueger at web.de
Wed May 26 00:04:16 CEST 2010

```   Dear List

I hope you can help me: I’ve got a dataframe (df) within which I am looking
for Peak Over Threshold values as well as the length of the events. An event
starts when walevel equals 5.8 and it should end when walevel equals the
lower threshold value (5.35).

I tried “clusters (…)” from “evd package”, and varied r (see example) but it
did not work for all events (again see example).

walevel <- c(5.75, 5.75, 5.75, 5.76, 5.80, 5.82, 5.85, 5.86, 5.91, 5.91,
5.88, 5.92, 5.99, 6.02, 6.00, 6.08, 6.11, 6.10, 6.10, 6.11, 6.14, 6.12,
6.15, 6.17, 6.15, 6.08, 6.01, 5.95, 5.89, 5.83, 5.77, 5.72, 5.70, 5.65,
5.59, 5.51, 5.43, 5.33, 5.30, 5.25, 5.22, 5.21, 5.19, 5.19, 5.19, 5.13,
5.15, 5.07, 5.04, 5.02, 4.99, 5.05, 5.07, 5.12, 5.17, 5.22, 5.32, 5.29,
5.33, 5.33, 5.36, 5.37, 5.42, 5.43, 5.48, 5.55, 5.57, 5.66, 5.68, 5.72,
5.77, 5.79, 5.81, 5.80, 5.80, 5.77, 5.72, 5.70, 5.66, 5.62, 5.62, 5.61,
5.59, 5.57, 5.51, 5.47, 5.41, 5.39, 5.40, 5.40, 5.42, 5.45, 5.47, 5.50,
5.50, 5.49, 5.43, 5.39, 5.33, 5.26)

day <- c(1:100)

df <- data.frame(day,walevel)

library(evd)
clusters(df\$walevel, u = 5.80, r = 1, ulow = 5.35, cmax = T, plot = T)
clusters(df\$walevel, u = 5.80, r = 50, ulow = 5.35, cmax = T, plot = T)

What have I done wrong?

Tonja
```