REPOSITORY
THE NICOLAUS COPERNICUS UNIVERSITY
IN TORUŃ
is an institutional repository of Nicolaus Copernicus University in Toruń. The task of the Repository is to promote scientific achievements and research conducted at NCU and to support teaching.
Recent Submissions
Intercity coopetition and regional innovation: The role of urban polycentricity
(Sage, 2026) Yang, Yuting; Lu, Jiayi; Derudder, Ben
Intercity coopetition—the dynamic interplay between cooperation and competition—is central to regional innovation, enabling knowledge exchange across cities. However, the spatial organization of these dynamics among functionally diverse cities and their implications for regional innovation outcomes remain underexplored. This study examines how urban polycentricity, captured through the balance of intercity coopetition relations, affects regional innovation performance. Methodologically, we develop an intercity coopetition index that incorporates both geographical overlap in collaboration networks and technological proximity. Empirically, we draw on longitudinal patent co-application data from nineteen Chinese urban regions between 1990 and 2022. Using fixed effect and instrumental variables models, we find that a balance in cooperation alone has a negative effect on regional innovation. In contrast, regional innovation performance is driven by the interaction between the strength of competitive ties and the balance of competition across cities. We conclude by discussing the policy implications of these findings for fostering spatially coordinated innovation systems.
Interconnected track and tech: the impact of multiplex transport and technology networks on labour market integration in the Yangtze River Delta, China
(Routledge, 2025-10) Liu, Xueqing; Derudder, Ben; Witlox, Frank
Despite growing scholarly attention to the role of urban networks in explaining regional integration dynamics, a more explicit focus on the multiplexity of infrastructure- and knowledge-based networks is required for understanding the nuanced ways in which cities regionally integrate. Applying a panel model to data for the Yangtze River Delta for the period 2014–2021, we juxtapose the impacts of transport and technology connections on labour market integration. To this end, we abstract both types of connections into a two-layer network and explore their (potential) interplays. Our analysis reveals that while transport networks show a positive correlation with labour market integration, technology networks demonstrate a complex U-shaped effect. We also find evidence for nuanced interactions in the multiplex network: (1) cities’ connectivity in both networks leads to a U-shaped effect on labour market integration due to the dominant role of technology connections; (2) cities’ interdependencies within the twolayer network lead to synergy effects, specifically manifested as increased integration of labour markets. We reflect on the broader implications of our findings for regional development strategies and discuss possible avenues for future research.
Polycentricity and technological diversification: divergent pathways across Chinese urban regions
(Taylor & Francis, 2026) Lu, Jiayi; Yang, Yuting; Cao, Zhan; Derudder, Ben
This paper examines how polycentricity shapes technological diversification in Chinese urban regions. Beyond morphological and functional dimensions, we introduce knowledge polycentricity, reflecting the balance of innovation across technological domains. Using patent data (2006–20), diversification is measured via relative relatedness density and estimated through fixed-effects and instrumental variable models. Findings highlight intra-regional functional polycentricity as the main driver, while other dimensions mainly act through interactions. Developmental heterogeneity produces distinct diversification pathways. Results call for innovation policies tailored to polycentricity characteristics and diversification strategies.
On Nondefinability of Interior-Connectedness via the Contact Relation
(Duke University Press, University of Notre Dame, 2026) Gruszczyński, Rafał; Menchón, Paula
This short paper is a small contribution to the field of Boolean contact algebras. We analyze the nondefinability of the property of interior-connectedness, and we prove certain minimality conditions for algebras and spaces that can be used in demonstrating that the aforementioned property cannot be expressed by means of contact within regular closed algebras.
Technological diversification in China: the role of intra- and extra-regional collaboration
(Taylor & Francis, 2026) Lu, Jiayi; Cao, Zhan; Derudder, Ben
This study investigates how intra- and extra-regional collaborations affect regional technological diversification in Chinese urban regions (URs), using a continuous indicator that places diversification along a spectrum from related to unrelated. Based on patent co-application data from 2001 to 2020, we analyse the intensity, technological diversity and the correlation of intra- and extra-regional collaborations. Our results show that the effects of (1) intra-regional collaboration intensity on related diversification and (2) extra-regional collaboration diversity on unrelated
diversification are both curvilinear. In addition, extra-regional intensity and the correlation between intra- and extra-regional collaborations foster related diversification. Moreover, economic disparities within URs reinforce, rather than weaken, the positive influence of intra-regional intensity and intra–extra technological correlation on related diversification. These results challenge conventional assumptions and highlight the importance of coordinated collaboration structures in promoting regional diversification, especially under uneven regional development conditions.