Sébastien Bourdin (p), Philippe Jean-Pierre (p), François Hermet

Jacek Chądzyński

The analysis of regional convergence processes in Europe is not new in the regional science literature (Abreu et al., 2005; Dall'erba and Le Gallo, 2008; Mohl, 2016; Bourdin, 2019). These empirical studies on economic convergence often present contradictory results. The question underlying these studies is not innocent. Can we really expect a convergence of European regional GDP per capita levels in the long run? The desire to reduce disparities between European regions is not new and was already included in the preamble of the Treaty of Rome (see Article 2 of the Treaty) (Mendez, 2011; Medeiros, 2016).
However, if this convergence dynamic appears to have been heterogeneous over time: the central regions, the eastern regions or the outermost regions of the European Union have thus experienced different rates of convergence. This spatial heterogeneity has been highlighted in the literature (Bourdin, 2019), which, for example, supports the importance of spatial factors such as distance and gravitational effects, or of great remoteness, such as that of the ORs, which are several thousand kilometres away. Similarly, several studies (Beine and Jean-Pierre, 2000; Diemer et al. 2022) have highlighted the existence of development traps leading to convergence clubs.
This reading of the dynamics in terms of clubs has the advantage of raising the risk of inappropriateness of convergence policies initially designed for a homogeneous set of converging regions, while studies such as Diemer et al. (2022) highlight the diversity of growth contexts. For example, these authors show that even initially prosperous, centrally located regions can experience a period of stagnation, while less prosperous regions further away from the centre can be associated with a more vigorous growth process. These results therefore seem to suggest that the associations between centre-dynamic and periphery-stagnation are not, or no longer, necessarily what we think. In other words, is the notion of peripheral regions as regions far from the centre and in difficulty still valid? Are the peripheral regions always what we think they are?
This is the question that this article will try to answer by mobilising the threshold effects that allow us to distinguish between different regimes of growth/convergence. More specifically, our work will complement the work of Beine and Jean-Pierre (2000) and Diemer et al. (2022) by mobilising the Hansen threshold test framework and drawing on the analysis of convergence dynamics proposed by Kant et al.

Geoffrey Caruso (p), Yong Chen

François Hermet

Despite an increased policy focus on urban density and compactness over the last decades, many cities still expand outward in a discontinuous fashion, leaving some land `leaped' over during the process, which fragments natural habitats and induces extra costs to society. We contribute the first leapfrog sprawl analysis spanning across all US metropolitan areas. We develop leapfrog indices and quantify the frequency of leapfrogs and the length of the leaps over the 29 million cells newly urbanised in the 380 US MSAs from 2001 to 2019 (7 images at 30m resolution). We analyze the change of these indices over time and space, then test for potential sources of leapfrogging with models using both disaggregate and MSA scale variables. We find that city size tends to increase leapfrogging but reduces the length of the leaps. A quicker urbanization has the most effect on increasing leapfrog distances, which we relate to expectations for these leaps to be filled in later on. We also find contradicting effects of density at the city and local scales, suggesting higher density cities have a push effect encouraging leapfrogging while local clusters are attractive and eventually form after leapfrogging. We find no apparent effect of income growth nor inequality that would push households further away to find affordable land. While most leapfrogging appears to be temporary on a 20 years scale at 30m resolution, its periodic volume remains a concern as well as the fact it is a dynamic process that continuously creates a fragmented pattern at the fringe.

Nataliia Moroziuk (p)

Geoffrey Caruso

Ukraine launched one of its most successful reforms – the decentralization reform. This process made it possible to form local self-government at the basic level – territorial communities that have sufficient powers and resources for their implementation, as well as to bring public services closer to each resident. With the beginning of the war, there was a return to centralization, in many communities power was passed to the military. It is obvious that the strong influence of the state and law enforcement agencies, especially in the border areas, will continue after the end of the war. Ukraine's challenges in urban development require the latest solutions in urban planning, the development of local economies in conditions of security risks, a balance between preserving the interests of the community and national security, and between decentralization processes and centralized state power. Ukraine can become an experimental creative space for implementing and testing new urban solutions.

Jacek Chądzyński (p), Jagoda Adamus

Nataliia Moroziuk

Implementing circular economy (CE) is not an easy task, but nowadays it seems to be a necessity. The transition from a traditional economy to a circular economy requires the efforts and support of stakeholders from various groups. Based on the quadruple helix model, groups implementing the circular economy include government, society, academia and companies. What can stand in the way of implementing a circular economy are the market failures, which are typical for traditional economies.
The concept of market failure has its origin in modern welfare economics. The most common categories are: public goods, externalities, imperfect competition, incompleteness of the market, and asymmetrical information.
In our research, we looked at the market failure from the perspective of the circular economy. In a circular economy, it is more often to identify the barriers which derail or slow down the transition towards a CE. The categories of barriers correspond to the problems that emerge during the transition to CE. The most common categories of barriers are: technological, economic, institutional and social.
Although the neoclassical economy and circular economy represent different approaches to the market and its imperfections, there is a link between them. Barriers that occurred in CE can be identified with classic market failures. This clear connection between market failures and CE barriers was a starting point for our research. The aim of the research was to identify market failure limiting the implementation of the circular economy in Poland and the Netherlands (Lodz and Friesland Regions).
We conducted two-step research: online survey and focus group interviews (FGI). The research was conducted among four groups: companies, government, academia and society.