Strong Coordination over Multi-hop Line Networks

We analyze the problem of strong coordination over a multi-hop line network in which the node initiating the coordination is a terminal network node. We assume that each node has access to a certain amount of randomness that is local to the node, and that the nodes share some common randomness, which are used together with explicit hop-by-hop communication to achieve strong coordination. We derive the trade-offs among the required rates of communication on the network links, the rates of local randomness available to network nodes, and the rate of common randomness to realize strong coordination. We present an achievable coding scheme built using multiple layers of channel resolvability codes, and establish several settings in which this scheme is proven to offer the best possible trade-offs.Comment: 35 pages, 9 Figures, 4 Tables. A part of this work were published in the 2015 IEEE Information Theory Workshop, and a part was accepted for publication in the 50th Annual Conference on Information Sciences and System

Network architecture, salience and coordination

This paper reports the results of an experimental investigation of monotone games with imperfect information. Players are located at the nodes of a network and observe the actions of other players only if they are connected by the network. These games have many sequential equilibria; nonetheless, the behavior of subjects in the laboratory is predictable. The network architecture makes some strategies salient and this in turn makes the subjects’ behavior predictable and facilitates coordination on efficient outcomes. In some cases, modal behavior corresponds to equilibrium strategies

Statistics of the contact network in frictional and frictionless granular packings

Simulated granular packings with different particle friction coefficient mu are examined. The distribution of the particle-particle and particle-wall normal and tangential contact forces P(f) are computed and compared with existing experimental data. Here f equivalent to F/F-bar is the contact force F normalized by the average value F-bar. P(f) exhibits exponential-like decay at large forces, a plateau/peak near f = 1, with additional features at forces smaller than the average that depend on mu. Computations of the force-force spatial distribution function and the contact point radial distribution function indicate that correlations between forces are only weakly dependent on friction and decay rapidly beyond approximately three particle diameters. Distributions of the particle-particle contact angles show that the contact network is not isotropic and only weakly dependent on friction. High force-bearing structures, or force chains, do not play a dominant role in these three dimensional, unloaded packings.Comment: 11 pages, 13 figures, submitted to PR

Adaptive Elastic Networks as models of supercooled liquids

The thermodynamics and dynamics of supercooled liquids correlate with their elasticity. In particular for covalent networks, the jump of specific heat is small and the liquid is {\it strong} near the threshold valence where the network acquires rigidity. By contrast, the jump of specific heat and the fragility are large away from this threshold valence. In a previous work [Proc. Natl. Acad. Sci. U.S.A., 110, 6307 (2013)], we could explain these behaviors by introducing a model of supercooled liquids in which local rearrangements interact via elasticity. However, in that model the disorder characterizing elasticity was frozen, whereas it is itself a dynamic variable in supercooled liquids. Here we study numerically and theoretically adaptive elastic network models where polydisperse springs can move on a lattice, thus allowing for the geometry of the elastic network to fluctuate and evolve with temperature. We show numerically that our previous results on the relationship between structure and thermodynamics hold in these models. We introduce an approximation where redundant constraints (highly coordinated regions where the frustration is large) are treated as an ideal gas, leading to analytical predictions that are accurate in the range of parameters relevant for real materials. Overall, these results lead to a description of supercooled liquids, in which the distance to the rigidity transition controls the number of directions in phase space that cost energy and the specific heat.Comment: 12 pages, 14 figure

Communication, coordination and networks

We study experimentally how the network structure and length of pre-play communication affect behavior and outcome in a multi-player coordination game with conflicting preferences. Network structure matters but the interaction between network and time effects is more subtle. Under each time treatment, substantial variations are observed in both the rate of coordination and distribution of coordinated outcomes across networks. But, increasing the communication length improves both efficiency and equity of coordination. In all treatments, coordination is mostly explained by convergence in communication. We also identify behaviors that explain variations in the distribution of coordinated outcomes both within and across networks

THE ROLE OF CROSS-CLASS ALLIANCES AND ELITES IN COORDINATED EMPLOYMENT RELATIONS IN DENMARK. CES Open Forum Series 2018-2019, September 4, 2018

Explanations for coordination between labor and capital in Northern Europe continue to cause debate among scholars of comparative political economy. On one hand, power resource scholars argue that strong trade unions promoting equality are necessary for coordination. On the other hand, employer-centered theories argue that employers are the primary actors in promoting coordination due to the comparative advantages stemming from coordination. To inform this debate, we study the case of Denmark by combining a unique database of 5.000 elite affiliations with 80 stakeholder interviews spanning a decade. We argue that trade union power resources are necessary for coordination. However, only when certain segments of labor can forge powerful alliances with key employers for the economy will coordination persist. The network analysis identifies a powerful cross-class alliance between trade unions and employer associations in manufacturing. Interviews with stakeholders show that coordination in industrial relations and related institutional spheres such as education and industrial policies serves this alliance’s interests in safeguarding international competitiveness of manufacturing. However, intra-class allegiances ensure that the alliance constantly has to consider the interests of outsider organizations