## 3 Results and Analysis
### Lane Changing Characteristics
#### 3.3.1 Distribution of LC Position  
Table 8 details the distribution of LC positions relative to the end of the diverging area under various CDs. These positions are categorized into three groups at distances of 460 m and 250 m, corresponding, respectively, to the diverging influence areas as defined by the Highway Capacity Manual (HCM) [49] and the starting of the deceleration lane. Figure 12 reveals a trend where the PMLC typically occurs later in the tunnel-interchange sections, with about 90% of drivers transitioning to the outer lane within these influence areas. Additionally, an increase in IV significantly influences MLC positioning. For instance,  
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \multirow{2}{*}{**Independent Variables**} & \multirow{2}{*}{**CD**} & \multicolumn{4}{c}{**Friedman Test**} & \multicolumn{4}{c}{**MANOVA**} \\  & & & **IV** & & **TC** & & **CD + TC** \\  & **Chi\({}^{2}\)** & \(p\) & **Chi\({}^{2}\)** & \(p\) & **Chi\({}^{2}\)** & \(p\) & **F** & \(p\) \\ \hline MLCD & **22.22** & 0.000 & 8.68 & 0.070 & **7.94** & 0.019 & / & / \\ MLCL & **12.18** & 0.032 & **9.65** & 0.047 & 4.98 & 0.082 & / & / \\ MLCA & **18.88** & 0.002 & 7.18 & 0.127 & 5.76 & 0.056 & 1.613 & 0.097 \\ DLCD & 9.97 & 0.076 & 3.74 & 0.442 & 3.70 & 0.157 & / & / \\ DLCL & 7.29 & 0.200 & 6.94 & 0.139 & 2.58 & 0.225 & 0.895 & 0.537 \\ DLCA & 9.45 & 0.092 & 5.27 & 0.261 & 4.56 & 0.102 & 0.854 & 0.576 \\ PMLC & **13.82** & 0.017 & 5.26 & 0.262 & 5.33 & 0.070 & & \\ PDLC & **11.61** & 0.041 & 1.28 & 0.864 & 3.48 & 0.175 & / & / \\ Gap & **12.39** & 0.030 & 7.51 & 0.111 & **17.20** & 0.000 & **3.303** & 0.001 \\ \hline \hline \end{tabular}  
* The bold terms indicate that the difference between the groups is significant at the 95% level.  
\end{table}
Table 7: [PERSON] and MANOVA test for LC indicators.  
increasing IV from 5 to 13 units results in the average LC position being delayed by around 20 m, suggesting that higher IV shifts the LC position closer to the exit area.  
We further extracted LC trajectories within the diverging influence area and applied smoothing and noise reduction to the curves, as depicted in Figure 13. The y-axis denotes the distance from the vehicle's left side to the road's left line. As CD decreases, there's an increase in MLCs near the directional sign. For a CD of 1000 m, the average PMLC is at 356 m, which shortens to 261 m in smaller spacing scenarios, suggesting that limited spacing affects drivers' sign recognition time and, consequently, their LC decisions.  
In terms of PMLC distribution, most vehicles are observed to diverge just after the taper of the deceleration lane, with about 96% diverging in the first half of this lane. However, for CDs of 100 m and 300 m, the point of divergence initiation is notably delayed.  
Figure 12: Distribution of PMLC under different CDs and IVs.  
Figure 13: LC trajectories under different CDs.  
The LC trajectories showcased in Figure 13 indicate a trend of more urgent MLCs in smaller spacing sections, particularly for CDs of 100 m and 300 m. This observation points to heightened risks associated with MLC. Interestingly, the trajectories for Diverging Lane Changes (DLCs) from the mainline to the auxiliary lane display less variation, suggesting a more consistent behavior pattern in DLCs regardless of CD.