Extremal analysis of processes sampled at different frequencies

The observed extremes of a discrete time process depend on the process itse lf and the sampling frequency. We develop theoretical results which show ho w to account for the effect of sampling frequency on extreme values, thus e nabling us to analyse systematically extremal data from series with differe nt sampling rates. We present statistical methodology based on these result s which we illustrate though simulations and by applications to sea-waves a nd rainfall data.