## 4 Results
### China's Urban Employment Multiplier

Table 2: Descriptive statistics of variables. consumer market-pull effect occasioned by the expansion of the trade sector is not as strong as in large cities. In addition, there is a less prominent employment multiplier in Northeast China, which has been related to emigration in recent years. The labor force outflow and the recession of the manufacturing industry make the labor force supply elasticity in Northeast China very low. Meanwhile, the income level in Northeast China also limits the realization of the employment multiplier. After identifying the characteristics of the spatial distribution of employment multiplier, the next obvious question is, how does this pattern connect with city size distribution? In fact, the relationship between city size and employment multiplier has attracted much scholarly attention and varied conclusions have been drawn in different places across the globe [21; 27]. In order to have a preliminary understanding of this issue in the case of Chinese cities, we divided the cities into different levels, according to their population sizes, made a statistical description of the employment multiplier of each level of the city, and then made a tentative explanation with the help of the existing literature and theory. Interesting patterns emerge from the statistics describing the results of the city-scale classification, as can be seen in Table 3. Cities with a population of less than 1 million have lower employment multipliers, with a mean of 0.81, a minimum of 0.31, and a maximum of 1.02. The employment multipliers show a slowly increasing trend with an increase in the city scale because most of these cities are economically underdeveloped within each provincial administrative unit in China. Although the degree of external contact is low, there will theoretically be lower employment spillover and a higher employment multiplier. However, the non-tradable sectors in these cities are small and single in type, which cannot maximize the employment effect brought about by the change in the trade sector. The employment multipliers of cities ranging from 1 million to 3 million are higher than those of the former, with a mean of 1.17, a maximum of 1.54, and a minimum of 0.57. The employment multiplier increased at a faster pace with the expansion of the scale. These cities generally have lower degrees of external contact than regional central cities and have certain levels of economic development and scales of local service  
Figure 2: The employment multiplier distribution of expanding cities in China. industries. Moreover, many of these cities are close to the central city and are affected by the spillover effect of the central city, thus having high employment multipliers. The urban employment multipliers for cities of 3-5 million decrease with the expansion of the urban scale. The employment multiplier reaches the maximum value, with a mean of 1.59, a maximum of 2.27, and a minimum of 1.09. This kind of city is a medium-sized city in China's urban system and is in the stage of rapid growth. Although it is large in scale, it is still at the stage of rapid polarization with a small spillover effect. Moreover, the trade sector based on the manufacturing industry is the main industry in such cities, so the expansion of the trade sector has a great impact on such cities. When the city population is larger than 5 million, the multiplier will start to decline with a mean of 1.08, a maximum of 1.26, and a minimum of 0.94, and the employment multiplier in the megalopolis is then relatively low. Most of these cities are China's regional hubs, with a declining share of manufacturing and a rising share of high-end services, such as financial innovation. Despite a significant employment multiplier, the driving effect of the manufacturing industry is weaker than that of small- and medium-sized cities. At the same time, the central roles of such cities mean that the spillover effect further weakens the employment multiplier.