This article analyzes the structure of socially embedded exchange under uncertainty in the context of a community currency system in Germany. We discuss three relational and path-dependent mechanisms—experience-based trust, networked reputation and public reputation—which serve as navigation practices to mitigate uncertainty. We furthermore associate these mechanisms with observable structures of exchange, namely repeated transactions and reciprocity, transitivity and provider activity, and discuss differences in product-inherent uncertainty as a source of variation in network structure. Based on original observations of more than 4000 transactions over a period of 8 years, we use relational event models to demonstrate that the history of transactions exhibits structure consistent with the three hypothesized mechanisms, with some variation across different types of transactions. This variation is partly in line with differences in product-inherent uncertainty, but we also discuss alternative sources of variation related to organizational and institutional conditions of the exchange system.

Time banks have become a popular type of civic organization constructed to facilitate egalitarian economic exchange through a community-bounded currency. Especially after the recent economic crises in Europe, the rise in the number of time banks has been accompanied by relative transience and sometimes short lifespans. We adopt a relational perspective to explore the dynamics of decline in the civic engagement of a time bank in southern Germany. Using methods of longitudinal social network analysis, we analyze the relational processes and individual trajectories of members within the emerging transaction network over a period of eight years. Rather than explaining why, we have found how relational trajectories of members through a structure of core and periphery have led to creeping decline in activity and membership. Given the repeated observation that time banks and other types of alternative economic practices are often characterized by considerable volatility and potential collapse, relational thinking and network analysis are especially suited to unpacking the underlying relational mechanisms that shape these outcomes of volatility and demise.

The bioeconomy comprises a range of industries that are related through their reliance on biomass and their use of biotechnology, such as agriculture, food processing, and parts of the life sciences. While the bioeconomy has received increasing attention in the context of innovation policy, the internal structure of its underlying technological field remains opaque, and little is known about the long-term processes through which its subdomains have co-evolved. It is precisely the structure (cohesion) of this field and its evolution (convergence) over the course of more than a century of technological development that this article seeks to disentangle. For this purpose, we draw on a dataset of more than 1.5 million patent families and use bibliometric methods and main path analysis to assess the internal and external cohesion of the field and trace its long-term technological development. Our analysis supports two main findings: First, instead of becoming more closed as a field, the cohesion of technologies within the bioeconomy with external technologies has increased over time. Second, the bioeconomy technological field shows clear signs of structural convergence over the second half of the 20th century, with the biochemical domain absorbing most of the trajectories of technological knowledge originating in the traditional application areas. As such, the study illustrates the long-term processes of technological cross-fertilization through which the bioeconomy, as an example of a heterogeneous technological field, developed its ‘backbone’ of technological knowledge.