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            they refer to. Most event logs considered thus far contained only historic, i.e., “post
            mortem”, event data. “Pre mortem” event data refer to cases that have not yet com-
            pleted. If a case is still running, i.e., the case is still “alive” (pre mortem), then it
            may be possible that information in the event log about this case (i.e., current data)
            can be exploited to ensure the correct or efficient handling of this case.
              “Post mortem” event data is most relevant for off-line process mining, e.g., dis-
            covering the control-flow of a process based on one year of event data. For online
            process mining, a mixture of “pre mortem” (current) and “post mortem” (historic)
            data is needed. For example, historic information can be used to learn a predictive
            model. Subsequently, information about a running case is combined with the pre-
            dictive model to provide an estimate for the remaining flow time of the case.
              The refined process mining framework also distinguishes between two types of
            models: “de jure models” and “de facto models”. A de jure model is normative, i.e., it
            specifies how things should be done or handled. For example, a process model used
            to configure a BPM system is normative and forces people to work in a particular
            way. A de facto model is descriptive and its goal is not to steer or control reality.
            Instead, de facto models aim to capture reality. The techniques presented in Chaps. 5
            and 6 aim to produce de facto models. Figure 9.1 also highlights that models can
            cover different perspectives, i.e., process mining is not limited to control-flow and is
            also concerned with resources, data, organizational entities, decision points, costs,
            etc. The two large arrows in Fig. 9.1 illustrate that de facto models are derived from
            reality (right downward arrow) and that de jure models aim to influence reality (left
            upward arrow).
              After refining event logs into “pre mortem” and “post mortem” and partitioning
            models into “de jure” and “de facto”, we can identify ten process mining related
            activities as shown in Fig. 9.1. These ten activities are grouped into three categories:
            cartography, auditing, and navigation.




            9.1.1 Cartography


            Process models can be seen as the “maps” describing the operational processes of
            organizations, i.e., just like geographic maps, process models aim to describe reality.
            In order to do this, abstractions are needed. For example, on a roadmap a highway
            may be denoted by an orange line having a thickness of four millimeters. In reality
            the highway will not be orange; the orange coloring is just used to emphasize the
            importance of highways. If the scale of the map is 1 : 500,000, then the thickness of
            the line corresponds to a highway of 2 kilometers wide. In reality, the highway will
            not be so broad. If the thickness of the line would correspond to reality (assuming
            the same scale), it would be approximately 0.05 millimeter (for a highway of 25 me-
            ters wide). Hence, the highway would be (close to) invisible. Therefore, the scale is
            modified to make the map more readable and useful. When making process models,
            we need to use similar abstractions. In Chap. 13, we will elaborate on the relation-
            ships between process maps and geographic maps. Also note that in Sect. 5.4.4 we
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