Since the implementation of the coordinated development strategy in the Beijing-Tianjin-Hebei (BTH) region, notable progress has been made in constructing a market-oriented system for scientific and technological innovation. However, issues such as uneven distribution of innovation factors and insufficient regional sharing of innovation outputs persist. Moreover, the lack of distinctive functional positioning among cities and an underdeveloped regional division of labor have hindered coordinated innovation. This study analyzes the flow of R&D personnel and funding across 13 BTH cities from 2010 to 2020 using a modified gravity model. It further examines the urban functional specialization pattern through a functional specialization index and evaluates the spatial impact mechanism of innovation factor flows on urban function optimization via a Spatial Durbin Model (SDM). Results reveal a "core-periphery" structure, with innovation factors highly concentrated in Beijing and Tianjin, while surrounding Hebei cities lag behind in specialization. The findings demonstrate that both R&D personnel and funding significantly promote the specialization of production, R&D, and management functions, though spatial spillover effects are uneven. The paper offers empirical evidence and policy implications for enhancing functional differentiation and promoting balanced regional development in urban agglomerations.

Yuyu Song, Zehui Cui. Innovation Factor Mobility and Urban Function Optimization: Evidence from the Beijing-Tianjin-Hebei Urban Agglomeration. Academic Journal of Humanities & Social Sciences (2025), Vol. 8, Issue 10: 9-15. https://doi.org/10.25236/AJHSS.2025.081002.

[1] Deng, J., Chen, T., & Zhang, Y. (2023). Effect of collaborative innovation on high-quality economic development in beijing–tianjin–hebei urban agglomeration—an empirical analysis based on the spatial durbin model. Mathematics, 11(8), 1909.

[2] Huang, X., & Liu, J. (2020). Regional economic efficiency and its influencing factors of Beijing-Tianjin-Hebei metropolitans in China based on a heterogeneity stochastic frontier model. Chinese Geographical Science, 30(1), 30-44.

[3] Liu, X., Zhang, X., Yuan, M., Liu, J., & Zhou, G. (2024). Spatial-temporal differentiation of urban eco-efficiency and its driving factors: A comparison of five major urban agglomerations in China. Plos one, 19(3), e0300419.

[4] An, X., Deng, H., Chao, L., & Bai, W. (2014). Knowledge management in supporting collaborative innovation community capacity building. Journal of Knowledge Management, 18(3), 574-590.

[5] Jain, M., & Korzhenevych, A. (2019). Detection of urban system in India: Urban hierarchy revisited. Landscape and Urban Planning, 190, 103588.

[6] Duranton, G., & Puga, D. (2004). From sectoral to functional urban specialization. Journal of Urban Economics, *57*(2), 343–370.

[7] Bade, F. J., Laaser, C. F., & Soltwedel, R. (2004). Urban specialization in the internet age - Empirical findings for Germany (Kiel Working Paper No. 1215). Kiel Institute for the World Economy.

[8] Yuan, X., Chen, B., He, X., Zhang, G., & Zhou, C. (2024). Spatial Differentiation and Influencing Factors of Tertiary Industry in the Pearl River Delta Urban Agglomeration. Land, 13(2), 172.

[9] Liu, X., Luo, Y., & Huang, M. (2022). Study on the Spatial Structure and City Form Construction of River Valley‐Type Cities in the Context of Artificial Intelligence—A Case Study of Northwest China. Wireless Communications and Mobile Computing, 2022(1), 4202745.

[10] Helpman, E. (1984). A simple theory of international trade with multinational corporations. Journal of Political Economy, *92*(3), 451–471.

[11] Razin, E., & Hazan, A. (1995). Industrial development and municipal reorganization: conflict, cooperation, and regional effects. Environment and Planning C: Government and Policy, 13(3), 297-314.

[12] Locay, L. (1990). Economic development and the division of production between households and markets. Journal of Political Economy, 98(5, Part 1), 965-982.

[13] Yeung, H. W. C. (2009). Transnational corporations, global production networks, and urban and regional development: A geographer's perspective on Multinational enterprises and the global economy. Growth and Change, 40(2), 197-226.

[14] Tavares, A. O., Monteiro, M., Barros, J. L., & Santos, P. P. (2019). Long-term land-use changes in small/medium-sized cities. Enhancing the general trends and local characteristics. European Planning Studies, 27(7), 1432-1459.

[15] Fang, C. (2015). Important progress and future direction of studies on China’s urban agglomerations. Journal of Geographical Sciences, 25(8), 1003-1024.

[16] Yu, H., Deng, Y., & Xu, S. (2018). Evolutionary pattern and effect of administrative division adjustment during urbanization of China: Empirical analysis on multiple scales. Chinese Geographical Science, 28(5), 758-772.

[17] Kang, L., & Ma, L. (2021). Expansion of industrial parks in the Beijing–Tianjin–Hebei urban agglomeration: A spatial analysis. Land, 10(11), 1118.

[18] Li, R., Yu, B., Wang, Q., Wu, G., & Ma, Z. (2024). Changes in economic network patterns and influencing factors in the urban agglomeration of Guangdong–Hong Kong–Macao Greater Bay Area: A comprehensive study. Buildings, 14(4), 1093.

[19] Yu, X., Wu, Z., Zheng, H., Li, M., & Tan, T. (2020). How urban agglomeration improve the emission efficiency? A spatial econometric analysis of the Yangtze River Delta urban agglomeration in China. Journal of environmental management, 260, 110061.