results for au:Lombardi_M in:cs
Mar 13 2018 cs.GT
This paper studies the effects of altruism and spitefulness in a two-sided market in which agents behave strategically and trade according to the Shapley-Shubik mechanism. By assuming that altruistic agents have concerns for others on the opposite side of the market, it shows that agents always find advantageous to trade. However, they prefer to stay out of the market and consume their endowments when there are altruistic agents who have concerns for the welfare of those on the same side of the market, or when there are spiteful agents. These non-trade situations occur either because the necessary first-order conditions for optimality are violated or because agents' payoff functions are not concave.
In Operation Research, practical evaluation is essential to validate the efficacy of optimization approaches. This paper promotes the usage of performance profiles as a standard practice to visualize and analyze experimental results. It introduces a Web tool to construct and export performance profiles as SVG or HTML files. In addition, the application relies on a methodology to estimate the benefit of hypothetical solver improvements. Therefore, the tool allows one to employ what-if analysis to screen possible research directions, and identify those having the best potential. The approach is showcased on two Operation Research technologies: Constraint Programming and Mixed Integer Linear Programming.
Movement coordination in human ensembles has been studied little in the current literature. In the existing experimental works, situations where all subjects are connected with each other through direct visual and auditory coupling, and social interaction affects their coordination, have been investigated. Here, we study coordination in human ensembles via a novel computer-based set-up that enables individuals to coordinate each other's motion from a distance so as to minimize the influence of social interaction. The proposed platform makes it possible to implement different visual interaction patterns among the players, so that participants take into consideration the motion of a designated subset of the others. This allows the evaluation of the exclusive effects on coordination of the structure of interconnections among the players and their own dynamics. Our set-up enables also the deployment of virtual players to investigate dyadic interaction between a human and a virtual agent, as well as group synchronization in mixed teams of human and virtual agents. We use this novel set-up to study coordination both in dyads and in groups over different structures of interconnections, with and without virtual agents. We find that, in dual interaction, virtual players manage to interact with participants in a human-like fashion, thus confirming findings in previous work. We also observe that, in group interaction, the level of coordination among humans in the absence of direct visual and auditory coupling depends on the structure of interconnections among participants. This confirms, as recently suggested in the literature, that different coordination levels are achieved over diverse visual pairings in the presence and in the absence of social interaction. We present preliminary experimental results on the effect on group coordination of deploying virtual computer agents in the human ensemble.