## 4 Results and Discussions
### Spatial-Temporal Patterns Analysis
In this pattern, the merging vehicles have an impact on the back traffic flow. 5. Merging Pattern E: At the moment of vehicle merging, there are rear vehicles and a LV. Studies have been conducted for this merging pattern. The traffic flow condition (bottleneck), the time gap and the space gap of the RV, and the speed of the merging vehicle are key factors when choosing merging types [16]. 6. Merging Pattern F: Merging vehicles merge behind alongside vehicle. There is a RV at the moment of merging. Compared to merging Pattern C, vehicle merges in Pattern F with vehicles behind it. It needs to be considered whether collisions will be generated and whether there will be some interference for the behavior of the RV. 7. Merging Pattern G: The alongside vehicle was originally located ahead on the target lane and the merging vehicle chose to accelerate to cut in. There is no LV after the merging vehicle completed merging. 8. Merging Pattern H: The difference with the merging Pattern G is the presence of a LV after the merge in merging Pattern H.  
The merging patterns are shown in Figure 7. The green vehicle is the merging vehicles. In this study, we selected a 100 m area both in front of and behind the target lane during the critical moment of merging behavior for analysis. The critical moment for vehicle merging is defined as when the physical center of the vehicle crosses the dotted line. Then, a statistical analysis was performed, which revealed that 35.25% of vehicles preferred Pattern B for merging, while only 0.03% opted for Pattern G or H. About 2% of the vehicles selected either Pattern C or F for merging, with a lower percentage second to Pattern G and H. The majority of merging vehicles prefer to merge behind the adjacent vehicle rather than cutting in. Figure 7: Schematic diagram of the Merging Patterns. The distribution of merging scenarios at four collection sites is shown in Figure 8, with each pie chart representing the distribution of a specific type of vehicle merging scenario at a data collection location. The distribution of merging patterns at four collection sites is shown in Figure 8, with each pie chart representing the distribution of a specific type of vehicle merging pattern at a data collection location. Observations at various locations indicate that cars and vans often prefer to merge when there are vehicles in front but none behind, suggesting that their drivers tend to adopt a conservative merging strategy to minimize potential conflicts with other vehicles. In contrast, truck drivers exhibit a preference for situations where there are no vehicles in front but some behind, possibly due to trucks' larger mass and braking distance necessitating greater safety margins during merging. Furthermore, aggressive merging behaviors by trucks in certain locations (over 15% in Pattern C and F) reveal that some drivers choose riskier strategies even in high-risk situations. Analyzing the selection of merging patterns reveals how human drivers guide their behavior based on different environmental states, and it highlights the significant impact of social preferences in the decision-making process. These findings are crucial for enhancing decision-making designs in autonomous vehicles to match the level of human drivers.