James Hollway

Multilevel embeddedness: The case of the global fisheries governance complex

Abstract This paper explores how bilateral and multilateral clustering are embedded in a multilevel system of interdependent networks. We argue that in complex systems in which bilateral and multilateral relations are themselves interrelated, such as global fisheries governance, embeddedness cannot be reduced to unipartite or bipartite clustering but implicates multilevel closure. We elaborate expectations for ties’ multilevel embeddedness based on network theory and substantive considerations and explore them using a multilevel ERGM. We find states’ bilateral ties are embedded in their shared membership in multilateral fisheries agreements, which is itself clustered around foci represented by similar content and treaty secretariats.

Beyond Trade: The Expanding Scope of the Nontrade Agenda in Trade Agreements

Increased complexity and density of transnational problems create unprecedented challenges and opportunities for contemporary international governance. “Issue linkage” is one institutional arrangement through which states address these changing circumstances. In this article, we examine the widening scope of the nontrade agenda in preferential trade agreements (PTAs). Nontrade issues (NTIs) such as human rights, democracy, environment, corruption, and labor standards are increasingly linked to PTAs. This issue linkage has important implications for understanding changing patterns of international trade, including the shift to PTAs and the rise of NTIs. We show that (1) states’ choices to commit to bilateral or plurilateral versions of traditional PTAs and to PTAs with NTIs are highly interdependent, (2) states increasingly incorporate NTIs into PTAs, as the associated costs of policy change are lowered through earlier agreements, and (3) network pressures favor the increasing adoption of bilateral and especially plurilateral NTIs over time. Using an original data set on NTIs covering 522 PTAs and spanning the period 1951 to 2009, we evaluate states’ motives behind the widening nontrade agenda of trade agreements using longitudinal network modeling. We employ multiplex coevolution stochastic actor-oriented network models in a novel design to account for interdependencies within and across states’ decisions. Following a descriptive mapping of major NTIs, we evaluate our theoretical arguments. Testing against the alternative explanations of power and commitment, we find that endogenous cost considerations are the most significant factor explaining the inclusion of NTIs into PTAs.

Change we can believe in: Comparing longitudinal network models on consistency, interpretability and predictive power

Abstract While several models for analysing longitudinal network data have been proposed, their main differences, especially regarding the treatment of time, have not been discussed extensively in the literature. However, differences in treatment of time strongly impact the conclusions that can be drawn from data. In this article we compare auto-regressive network models using the example of TERGMs – a temporal extensions of ERGMs – and process-based models using SAOMs as an example. We conclude that the TERGM has, in contrast to the ERGM, no consistent interpretation on tie-level probabilities, as well as no consistent interpretation on processes of network change. Further, parameters in the TERGM are strongly dependent on the interval length between two time-points. Neither limitation is true for process-based network models such as the SAOM. Finally, both compared models perform poorly in out-of-sample prediction compared to trivial predictive models.

Dynamic Network Actor Models: Investigating Coordination Ties through Time:

Important questions in the social sciences are concerned with the circumstances under which individuals, organizations, or states mutually agree to form social network ties. Examples of these coordination ties are found in such diverse domains as scientific collaboration, international treaties, and romantic relationships and marriage. This article introduces dynamic network actor models (DyNAM) for the statistical analysis of coordination networks through time. The strength of the models is that they explicitly address five aspects about coordination networks that empirical researchers will typically want to take into account: (1) that observations are dependent, (2) that ties reflect the opportunities and preferences of both actors involved, (3) that the creation of coordination ties is a two-sided process, (4) that data might be available in a time-stamped format, and (5) that processes typically differ between tie creation and dissolution (signed processes), shorter and longer time windows (windowed processes), and initial and repeated creation of ties (weighted processes). Two empirical case studies demonstrate the potential impact of DyNAM models: The first is concerned with the formation of romantic relationships in a high school over 18 months, and the second investigates the formation of international fisheries treaties from 1947 to 2010.

Multilevel Bilateralism and Multilateralism: States’ Bilateral and Multilateral Fisheries Treaties and Their Secretariats

Actors often face challenges demanding bilateral or multilateral cooperation, each with quite different implications. Analytically separating these levels of activity raises the question whether they are driven by similar or different factors. We argue that to answer such questions, one should treat them as interlocking unipartite and bipartite networks, respectively, in a multilevel network. Here we employ multilevel ERGMs to model how bilateral and multilateral fisheries treaties between states, as well as relationships between multilateral treaties, are structured. We find that states prefer either bilateralism or multilateralism and, amongst multilateral treaties, those that are managed or similar.