Abstract: The disclosure relates to a method for determining diagnostic models for time series of a technical system and to a diagnostic method. In the method for determining one or more diagnostic model/s for time series of a technical system for the purpose of diagnosing an event, firstly, one or more diagnostic models are formulated and, in a first act, possible extensions of the diagnostic model/s are determined; in a second act, for each extension of the/each diagnostic model/s, a set of sequences is determined from the time series, in which the extension is contained; in a third act, each sequence of said set is tested to determine whether the sequence is connected with the event; and in a fourth act, the/those extensions for which the ratio of the number of sequences of the set which are connected with the event to the number of sequences of the set is largest, is/are set as the new diagnostic model.