Frequency of exceedance any peak exceeding is . Its complement, is the probability of exceedance, the probability that has been exceeded at least once by time . This probability can be useful to estimate whether an extreme event will occur during a specified time period, such as the lifespan of a structure or the duration of an operation. If is small, for example for the frequency of a rare event occurring in a short time period, then Under this assumption, the frequency of exceedance is equal to the probability of exceedance per unit time, , and the probability of exceedance can be computed
Shannon capacity of a graph no two of these code words can be confused with each other. By using this method, in "n" steps of communication, the sender can communicate up to 5 messages, significantly more than the 2 that could be transmitted with the simpler one-digit code. The effective number of values that can be transmitted per unit time step is (5) = . In graph-theoretic terms, this means that the Shannon capacity of the 5-cycle is at least . As showed, this bound is tight: it is not possible to find a more complicated system of code words that allows even more different