Event diagram
Events define the fact that the state of information objects has changed. Thus, every event references particular information objects of the data model and defines the status of this information object at a given point in time.
First of all, events are roughly specified in a top-down procedure (example: Order processed). The next level of detail in process modeling involves the specification of detailed events that, in certain combinations, cause the event to occur at the rough level. For example, the occurrence of the events Feasibility checked, Order header registered, and Order items registered can, in sum, define the Order processed status.
You can use the event diagram to display these event correlations at the rough and detail modeling levels. For this purpose, an event at the rough level can be assigned an event diagram displaying the events and the corresponding operators at the detail level (which results in the formation of a hierarchy). Moreover, you can include information objects of the data model in this model type and link them to the events. Thus you specify the event which defines the state change of a given information object.
An example is shown in the following figure.