## 4 Results
### Experimental Results
#### 4.3.2 Real Log  
Using real event logs for experiments, compare the accuracy and running time of the Direct(dfr) and Indirect(dfr) methods discussed in this paper with the four methods proposed in reference [1]: (Direct, Direct(\(\alpha=1/\left|\text{A}\right|\)), Indirect and Indirect(\(\alpha=1/\left|\text{A}\right|\))), and the least-frequent-first chaotic activity filtering approach Infrequent. In experiments with real event logs, the quality of chaotic activity filtering technology was evaluated by an indirect method, which evaluated the quality of the model obtained after the process mining of the event logs obtained after chaotic activity filtering had been completed. The model evaluation method used in this section is to calculate the harmonic mean between the _fitness_ and _precision_ of the model. An intuitive presentation of the effectiveness of the chaotic activity filtering method is obtained by observing the direct following graph corresponding to the event log. Taking event log Sepsis as an example, Figure 2 shows the direct following graph of Sepsis. Based on the direct following graph of logs, it can be seen that the direct following relationship between activities in event logs is chaotic. Figure 3 shows the direct following graph corresponding to all filtered event logs obtained by filtering the logs using the direct chaotic activity filtering method proposed in this chapter. According to Figure 3, the event log Sepsis is filtered by the direct chaotic activity filtering approaches proposed in this paper to obtain three filtered logs, and the number of remaining activities in the logs is nine and seven in turn. Figure 4 shows the direct following graph corresponding to all filtered event logs obtained by filtering the logs using the indirect chaotic activity filtering method proposed in this chapter. In Figure 4, the event log Sepsis is filtered by the indirect chaotic activity filtering approaches proposed in this paper to obtain three filtered logs, and the number of remaining activities in the logs is eight and seven in turn. Multiple filtered event logs can be obtained from original event logs after chaotic activity filtering. Figure 2 to Figure 4 show the direct following graphs of all filtered event logs obtained from real event logs after filtering. It can be seen from the direct following graph that after the filtering of chaotic activities, the chaos degree of the direct following  
Figure 2: Direct following graph for Sepsis. relationship between activities in the log is significantly reduced. As the number of activities decreases, the confusion of the direct following relationship between activities decreases. Moreover, according to the conditions proposed in this paper for the identification of chaotic activities, the chaotic activity filtering method based on the relationship between activities can stop filtering when the number of remaining activities reaches a certain degree, which is related to the log. As can be seen from the figure, the filtering methods proposed above can filter multiple chaotic activities in each run, so the algorithm can improve the efficiency of the chaotic activity filtering approach. These methods can control the amount of remaining activities in the filtered log within a reasonable range, so as to ensure the integrity of the event log to a certain extent. After filtering the chaotic activities in the event log, by observing the direct following graph of the filtered log, it can be found that the chaotic degree of the relationship between activities in the log is effectively reduced. Therefore, these methods can effectively reduce the chaotic degree of the event log and improve the quality of the model. The results of the experiment are revealed in Figures 5-7, and each picture consists of two parts. Part (a) describes the contrast of model quality changes with the reduction of the amount of remaining activities in the event log after filtering, in other words, the  
Figure 4: Direct following graph for Sepsis-indirect.