# Promotion Effects of High-Speed Rail on Urban Development: Evidence from Three Lines in China
## 3 Results
### Analysis Considering Relevant Influencing Factors  
#### 3.2.1 Different Performances of the Three Lines  
The locations of the Beijing-Shanghai, Beijing-Guangzhou, and Harbin-Dalian HSR lines within China are significantly different. The Beijing-Shanghai line passes through the eastern coastal region, which has many large cities and relatively advanced economies. The Beijing-Guangzhou line traverses several central provinces, with its stations primarily in small to medium-sized cities, aside from provincial capitals, and has a relatively moderate level of economic development. The Harbin-Dalian line is situated in the northeastern region, where population outflow has been notable In recent years, and the economic growth rate is relatively slow. Given the significant differences in the locations of the three lines, it is necessary to compare the average performance of cities along these lines in terms of \(D_{aR}\), \(D_{aE}\), \(D_{aG}\), and \(D_{aL}\). The calculation results are shown in Table 1.  
It can be seen that the performance of cities along different lines in terms of population agglomeration varies significantly. The Beijing-Shanghai HSR has the most significant effect on promoting the agglomeration of resident and employment populations, with \(D_{aR}\) and \(D_{aE}\) values reaching 0.0626 and 0.0857, respectively. The Beijing-Guangzhou HSR's effect on population agglomeration is not very pronounced, with \(D_{aR}\) and \(D_{aE}\) values at only 0.0157 and 0.0328, respectively. The Harbin-Dalian HSR shows a relatively significant effect on resident population agglomeration, second only to the Beijing-Shanghai line, with \begin{table}
\begin{tabular}{c c c c c} \hline
**Line** & **Average Value of \(D_{aR}\)** & **Average Value of \(D_{aE}\)** & **Average Value of \(D_{aG}\)** & **Average Value of \(D_{aL}\)** \\ \hline Beijing-Shanghai HSR & 0.0626 & 0.0857 & \(-\)0.1009 & 0.0368 \\ Beijing-Guangzhou HSR & 0.0157 & 0.0328 & 0.0296 & 0.0060 \\ Harbin–Dalian HSR & 0.0505 & 0.0236 & \(-\)0.0773 & 0.0044 \\ \hline \end{tabular}
\end{table} 
Table 1: The average performance of \(D_{a}\) values for different indicators in cities along the three lines. a \(D_{aR}\) value of 0.0505, but has a negligible effect on employment population agglomeration, with a \(D_{aE}\) value of only 0.0236. Comparing the \(D_{a}\) values for resident and employment populations, it can be observed that both the Beijing-Shanghai HSR and Beijing-Guangzhou HSR have a more pronounced effect on the agglomeration of employment populations, whereas the Harbin-Dalian HSR has a more significant effect on the agglomeration of the resident population. The impact of the three lines on the economic growth of cities also shows significant differences. The Beijing-Guangzhou HSR demonstrates a positive effect, with a \(D_{aG}\) value of 0.0296. In contrast, both the Beijing-Shanghai HSR and Harbin-Dalian HSR exhibit negative impacts, with \(D_{aG}\) values of \(-0.1009\) and \(-0.0773\), respectively. The Beijing-Shanghai HSR passes through relatively developed areas where cities face numerous economic development opportunities. Both the experimental and control group cities in this region experienced high GDP growth over the ten years, increasing by 142.60% and 152.68%, respectively. The HSR factor is just one of the many conditions promoting the economic development of cities in this region. Among the control group cities in this area, some have large ports (e.g., Taizhou), and some are close to metropolitan areas (e.g., Taicang). Additionally, this region generally emphasizes balanced regional development. For example, Jiangsu Province has been actively promoting coordinated development between the southern, central, and northern areas in recent years, leading to higher economic growth rates in some cities that received HSR later.