Talking Behind Your Back: Communication and Team Cooperation

Communication is one of the most effective devices in promoting team cooperation. However, asymmetric communication sometimes breeds collusion and hurts team efficiency. Here, we present experimental evidence showing that excluding one member from team communication hurts team cooperation; the communicating partners collude in profit allocation against the excluded member, and the latter reacts by exerting less effort. Allowing the partners to reach out to the excluded member partially restores cooperation and fairness in profit allocation, but it does not stop the partners from talking behind that member’s back even when they could have talked publicly. The partners sometimes game the system by tricking the excluded member into contributing but then grabbing all profits for themselves. This paper was accepted by Axel Ockenfels, behavioral economics and decision analysis.

BirdQuestVR: a cross-platform asymmetric communication game

BirdQuestVR is a cross-platform asymmetric communication game between one player in Virtual Reality and another on a mobile device. The game explores asymmetric co-operative gaming in a shared physical space, taking the physical surroundings of the VR user into account in its design. Asymmetric games feature different rules, abilities, or objectives for different players, generating unique and nuanced game experiences. Multiplayer asymmetric games in particular have been shown to increase teamwork and a collaborative mindset even after a play session has ended. Asymmetric design is commonplace in both digital and analog games but has yet to see widespread adoption in the emerging Virtual Reality (VR) gaming space. BirdQuestVR seeks to leverage the affordances of current consumer-grade VR headsets to build asymmetric gameplay around communication, embodied performance, and physical humour. Keywords: Asymmetric, Virtual Reality, Cross-Platform, Social Play, Avatar Embodiment

BirdQuestVR: a cross-platform asymmetric communication game

BirdQuestVR is a cross-platform asymmetric communication game between one player in Virtual Reality and another on a mobile device. The game explores asymmetric co-operative gaming in a shared physical space, taking the physical surroundings of the VR user into account in its design. Asymmetric games feature different rules, abilities, or objectives for different players, generating unique and nuanced game experiences. Multiplayer asymmetric games in particular have been shown to increase teamwork and a collaborative mindset even after a play session has ended. Asymmetric design is commonplace in both digital and analog games but has yet to see widespread adoption in the emerging Virtual Reality (VR) gaming space. BirdQuestVR seeks to leverage the affordances of current consumer-grade VR headsets to build asymmetric gameplay around communication, embodied performance, and physical humour. Keywords: Asymmetric, Virtual Reality, Cross-Platform, Social Play, Avatar Embodiment

A theory of RPC calculi for client–server model

With multi-tier programming languages, programmers can specify the locations of code to run in order to reduce development efforts for the web-based client–server model where programmers write client and server programs separately and test the multiple programs together. The RPC calculus, one of the foundations of those languages by Cooper and Wadler, has the feature of symmetric communication in programmer’s writing arbitrarily deep nested client–server interactions. The feature of the calculus is fully implemented by asymmetric communication in trampolined style suitable for the client–server model. However, the existing research only considers a stateless server strategy in which all server states are encoded for transmission to the client so that server states do not need to be stored in the server. It cannot always correctly handle all stateful operations involving disks or databases. To resolve this problem, we first propose new stateful calculi that fully support both symmetric communication from the programmer’s viewpoint and asymmetric communication in its implementation using trampolined style. All the existing calculi either provide only the feature of asymmetric communication or propose only symmetric implementation suitable for the peer-to-peer model, rather than the client–server model. Second, the method used to design our stateful server strategy is based on a new locative type system which paves the way for a theory of RPC calculi for the client–server model. Besides proposing the new stateful calculi, this theory can improve the existing stateless server strategy to construct new state-encoding calculi that eliminate runtime checks on remote procedure calls present in the existing strategy, and it enables us to design a new mixed strategy that combines the benefits of both kinds of strategies. As far as we know, there are no typed multi-tier calculi that offer programmers the feature of symmetric communication with the implementation of asymmetric communication under the three strategies together.

Solving Multi-agent Path Finding on Strongly Biconnected Digraphs

Much of the literature on suboptimal, polynomial-time algorithms for multi-agent path finding focuses on undirected graphs, where motion is permitted in both directions along a graph edge. Despite this, traveling on directed graphs is relevant in navigation domains, such as path finding in games, and asymmetric communication networks.We consider multi-agent path finding on strongly biconnected directed graphs. We show that all instances with at least two unoccupied positions have a solution, except for a particular, degenerate subclass where the graph has a cyclic shape. We present diBOX, an algorithm for multi-agent path finding on strongly biconnected directed graphs. diBOX runs in polynomial time, computes suboptimal solutions and is complete for instances on strongly biconnected digraphs with at least two unoccupied positions. We theoretically analyze properties of the algorithm and properties of strongly biconnected directed graphs that are relevant to our approach. We perform a detailed empirical analysis of diBOX, showing a good scalability. To our knowledge, our work is the first study of multi-agent path finding focused on directed graphs.