This study explores the relationship between railroad integration and regional development on the European periphery between 1870 and 1910, based on a regional data set including 291 spatial units. Railroad integration is proxied by railroad density, while per capita GDP is used as an indicator of economic development. The period under study is of particular relevance as it has been associated with the second wave of railroad construction in Europe and also coincides with the industrialization of most of the continent. Overall, we found that railroads had a significant and positive impact on the growth of per capita GDP across Europe. The magnitude of this relationship appears to be relatively modest, but the results obtained are robust with respect to a number of different specifications. From a geographical perspective, we found that railroads had a significantly greater influence on regions located in countries on the northern periphery of Europe than in other outlying areas. They also helped the economies of these areas to begin the process of catching up with the continent’s industrialized core. In contrast, the regions on the southern periphery showed lower levels of economic growth, with this exacerbating the preexisting divergence in economic development. The expansion of the railroad network in them was unable to homogenize the diffusion of economic development and tended to further benefit the regions that were already industrialized. In most of the cases, the capital effect was magnified, and this contributed to the consolidation of newly created nation-states.

This research seeks to understand the economic and social interaction patterns among dispersed Piedmont Village Tradition communities in the North American Southeast, AD 1200–1600. Piedmont Village Tradition communities lived adjacent to Mississippian societies and have been categorized as a peripheral society because of this spatial relationship. We examine economic behaviors by constructing fall-off curves of local versus nonlocal lithic material proportions at settlement sites and examining the reduction behaviors and tool types at sites. The results support a possible gateway model for the acquisition and distribution of nonlocal materials that linked spatially proximate communities. To examine social interaction patterns, we conducted a Brainerd-Robinson analysis of ceramic attributes from six sites and combined our results with work by Rogers (1993). The results show sites with stylistic similarities are not the same sites that share lithic resources. We conclude that these spatially non-overlapping artifact patterns result from a heterarchical social organization with a high degree of independence between economic and social interactions. Finally, we contextualize our results within the current knowledge of Mississippian and Piedmont Village Tradition societies in the region to broaden the discussion of gateways in reciprocity-based economies, societies traditionally thought of as peripheral to complex societies, and coalescence.

Statistical inference on graphs often proceeds via spectral methods involving low-dimensional embeddings of matrix-valued graph representations such as the graph Laplacian or adjacency matrix. In this paper, we analyze the asymptotic information-theoretic relative performance of Laplacian spectral embedding and adjacency spectral embedding for block assignment recovery in stochastic blockmodel graphs by way of Chernoff information. We investigate the relationship between spectral embedding performance and underlying network structure (e.g., homogeneity, affinity, core-periphery, and (un)balancedness) via a comprehensive treatment of the two-block stochastic blockmodel and the class of K-blockmodels exhibiting homogeneous balanced affinity structure. Our findings support the claim that, for a particular notion of sparsity, loosely speaking, “Laplacian spectral embedding favors relatively sparse graphs, whereas adjacency spectral embedding favors not-too-sparse graphs.” We also provide evidence in support of the claim that “adjacency spectral embedding favors core-periphery network structure.”

This paper explores the structural changes in the international organization of automotive production since the early 1990s. We apply descriptive network measures to international trade data for the period 1993–2013 for three automotive component groups with different technological intensity, with the aim of understanding (1) how the automotive international trade network has changed since the beginning of the 1990s; (2) whether regionalization has increased over time; (3) how the role that rising powers play within and between regions interacts with regionalization patterns. Our findings suggest that the structure of trade has changed significantly over the last two decades in all components. The network for electric and electrical parts and engines has evolved to become more hierarchical, with a cohesive core tied to hangers-on in the periphery, while the opposite has happened for rubber and metal. Regionalization patterns also show important differences across components. Finally, we have found an apparent association between the strengthening of regionalization patterns and the role played by traditional players and rising powers.

Many hierarchically modular systems are structured in a way that resembles an hourglass. This “hourglass effect” means that the system generates many outputs from many inputs through a relatively small number of intermediate modules that are critical for the operation of the entire system, referred to as the waist of the hourglass. We investigate the hourglass effect in general, not necessarily layered, hierarchical dependency networks. Our analysis focuses on the number of source-to-target dependency paths that traverse each vertex, and it identifies the core of a dependency network as the smallest set of vertices that collectively cover almost all dependency paths. We then examine if a given network exhibits the hourglass property or not, comparing its core size with a “flat” (i.e., non-hierarchical) network that preserves the source dependencies of each target in the original network. As a possible explanation for the hourglass effect, we propose the Reuse Preference model that captures the bias of new modules to reuse intermediate modules of similar complexity instead of connecting directly to sources or low complexity modules. We have applied the proposed framework in a diverse set of dependency networks from technological, natural, and information systems, showing that all these networks exhibit the general hourglass property but to a varying degree and with different waist characteristics.

A cremation and subsequent burial can be analysed as a set of technological, social and ritual transformations. It consists of three parts: first, the place where the body was burnt or cremated; secondly, the intermediary period in time and space, where the cleaned bones are often transported somewhere else; this interval increases the room for manoeuvre in those aspects which are concerned with the renewal, reorganization and re-legitimization of relations between the living; and, finally, the place where the ashes or the bones were deposited or buried, which may be the same place where the body was cremated, but normally it is not. Thus the urn represents the place where the deceased died, the cremated bones are from the rite of cremation, whereas the burial of the urn and the deposition of undamaged artefacts are from the final burial site, where other rituals were performed by the descendants, relatives and others. The distribution of urns may illuminate the notion that distance has hardly been a barrier and that people from, the ‘northern margins’ have travelled all over Europe from the late Bronze Age to the Viking period. This approach attacks the dual cultural hypothesis and some elements of core–periphery models.