## 4 Results
### Simulation Calibration Results  
Figure 7 represents the variations in RMSE and NRMSE, respectively, between simulated and real-world space mean speeds of the target links in the first time period. Overall, the errors show a decreasing trend along with iterations, and reach the threshold at around 18 iterations. We can observe a slight increase in RMSE and NRMSE during the eleventh calibration iteration. This could result from the insensitivity between speed and traffic volume so that some links may have over-calibration. Nevertheless, our calibration process accurately identifies and corrects such over-calibration, ensuring the accuracy of the final results. In the subsequent process, the error values resumed their downward trend. Figure 8 depicts the variations in RMSE and NRMSE, respectively, between simulated and real-world space mean speeds of the target links across all time periods. Similarly, the errors exhibit a decreasing trend and become stable after around 380 iterations. During the intermediate stages of calibration, there are sharp decreases in error values to varying degrees. This is because the calibration process is performed on a per-time-period basis, and as the model calibration for the current time period proceeds, the rate of error reduction gradually slows down. Once the error for the current time period satisfies the threshold \\(\\lambda\\), we fix the travel demand for that period and proceed to calibrate the next time period. The transition between calibration periods results in a sudden drop in error, followed by a gradual slowdown as the calibration iterations continue. Notably, as the number of iterations for each time period increases, the rate of errors decreases more rapidly, indicating that subsequent time periods are easier to calibrate than previous periods. Regarding the speed of the calibration iteration process, the average time spent per iteration during the calibration of the first time slice in this study was only 44 s. As the travel demand was scaled up, the overall travel plan for the simulation increased, resulting in a corresponding increase in the computation time for the average travel time of road segments within the simulation. Consequently, the final calibration iteration for the last time slice took 155 s, and the entire calibration process for the travel demand of the simulation model lasted approximately 11 h.  
The variations in errors between the simulated and real-world space mean the speeds of the target links for each time period before and after calibration and the variations in errors across all time periods are presented in Table 5. Through a comparative analysis, it is clearly observed that there is a significant improvement in error during the calibration process. After calibrating the simulation model, the RMSE of the average speed for the target road segment across all time periods decreased from 5.217 m/s to 1.939 m/s. The NRMSE for each individual time period was reduced to below 30%, while the overall NRMSE across all time periods decreased from 63.9% to 24.1%. In the final iteration, the travel demand is 296,906 trips. Compared to all the original 68,850 data from Type A and Type B data, we can conclude that the original data significantly underestimated the actual transportation demand, indirectly indicating the limited coverage of LBS user data. Figure 8: Variation in error between the space mean speeds of the target links in simulation and reality in all time periods: (**a**) the variations in RMSE between simulated and real-world space mean speeds of the target links in all time periods; (**b**) the variations in NRMSE between simulated and real-world space mean speeds of the target links in all time periods.