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6.4 Region-Based Mining                                         173
























            Fig. 6.9 Two parent models (top) and two child models resulting from a crossover. The crossover
            points are indicated by the dashed lines













            Fig. 6.10 Mutation: a place is removed and an arc is added

            time to discover a model having an acceptable fitness. In theory, it can be shown that
            suitably chosen genetic operators guarantee that eventually a model with optimal
            fitness will be produced. However, in practice this argument is not useful given the
            potentially excessive computation times. One advantage is that it is easy to provide
            parallel implementations of genetic process mining. It is possible to partition the
            individuals or the event log over multiple computation nodes (e.g., nodes in a com-
            putational computer grid) [16]. It is also useful to combine heuristics with genetic
            process mining. In this case, genetic process mining is used to improve a process
            model obtained using heuristic mining. This saves computation time and may re-
            sult in models that could never have been obtained through conventional algorithms
            searching only for local dependencies.



            6.4 Region-Based Mining

            In the context of Petri nets, researchers have been looking at the so-called synthe-
            sis problem, i.e., constructing a system model from a description of its behavior.
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