Economy-driven Shaping of Social Networks and Emerging Class Behaviors

International audienceIn this paper, we propose an agent-based analysis of a cumulative social-network game. Agents grant loans to their neighbours to maximize their intertemporal utility function. With a complete graph, we show that interest rates converge toward the theoretical equilibrium, even if ther is no centralized walrasian auctioneer and no preference transmition between agents. With a dynamic network, we explain why the network can't stabilize with a rational strategy. We introduce death and show that, even if the rational strategy is individually the best, the situation where three different strategies coexist is better for the global welfare

Negotiation protocols and dynamic social networks

International audienceMulti-agent system make it possible to investigate systems with complex interaction protocols and limited information sharing. Our objective in this paper is to emphasize the impact of exchange protocols in social networks. The presented MAS considers a loan-granting scenario where each agent can borrow/lend money to its neighbors and/or consume it. We define six interaction protocols, ranging from fixed equilibrium rate loans to double-free auctions, and we study their impact on the network structure and the global welfare of the economy. Further, the agent fitness is investigated in relation with its connectivity (number of neighbors) and eccentricity (longest path to the other agents)

Prêts bilatéraux et réseaux sociaux

International audienceIn this paper, our goal is to use Agent-Based Computational Economics and traditional economic methodology to study a path-dependent context: loan granting in a dynamicsocial network with intertemporal utility functions. We study the evolution of the graph andmacro variables, and show that interest rate converge even if the network is locally unstable.We also study the impact of agent strategies on global welfare of the economy, and concludethat a diversity of strategies increases global welfare.Dans cet article, nous étudions l'évolution d'un réseau social dans lequel des agents réalisent des prêts bilatéraux guidés par leurs préférences intertemporelles. Nous étudions l'évolution du graphe et de variables macroéconomiques et montrons notamment que le taux d'intérêt converge malgré une instabilité locale du graphe. Puis nous nous intéressons au bien être global de l'économie dans le cas où les agents disposent d'une stratégie pour déterminer leurs liens sociaux et montrons en particulier, dans le cas ou les agents sont mortels, que la diversité des stratégies conduit à un accroissement du bien être collectif

Heath-related quality of life in thyroid cancer patients following radioiodine ablation

<p>Abstract</p> <p>Background</p> <p>There is limited information about the medium to long-term health-related quality of life (QOL) in thyroid cancer patients after initial therapy and the existing studies suffer from limitations. The aim of the study was to assess the determinants of medium-term QOL after the initial therapy.</p> <p>Methods</p> <p>Following a total thyroidectomy, 88 thyroid cancer patients received either rhTSH or hypothyroid-assisted radioiodine ablation (RRA) using 3.7 GBq (100 mCi) of radioiodine. QOL evaluation of the patients using the validated Functional Assessment of Chronic Illness & Therapy (FACIT) was performed at the time of inclusion (t0) and later at the 9-month post-RRA (t1).</p> <p>Results</p> <p>83 patients were eligible for the final evaluation. Medium-term FACIT scores were not statistically different between t0 and t1 patients. All but one domain of the QOL score was similar between t0 and t1. Using a multivariate analysis, only age and immediate postoperative QOL scores were found to be determinants of the overall medium term 9-month QOL scores. Analysis showed that 'high QOL levels' (baseline and 9-month) and 'no depression', 'low anxiety levels', were associated with '<45yrs', 'men', 'partner', and 'rhTSH stimulation'.</p> <p>Conclusions</p> <p>The use of radioiodine ablation does not seem to affect the medium term QOL scores of patients. Medium-term QOL is mainly determined by pre-ablation QOL. The assessment of baseline QOL might be interesting to evaluate in order to adapt the treatment protocols, the preventive strategies, and medical information to patients for potentially improving their outcomes.</p

Prêts bilatéraux et réseaux sociaux

International audienceIn this paper, our goal is to use Agent-Based Computational Economics and traditional economic methodology to study a path-dependent context: loan granting in a dynamicsocial network with intertemporal utility functions. We study the evolution of the graph andmacro variables, and show that interest rate converge even if the network is locally unstable.We also study the impact of agent strategies on global welfare of the economy, and concludethat a diversity of strategies increases global welfare.Dans cet article, nous étudions l'évolution d'un réseau social dans lequel des agents réalisent des prêts bilatéraux guidés par leurs préférences intertemporelles. Nous étudions l'évolution du graphe et de variables macroéconomiques et montrons notamment que le taux d'intérêt converge malgré une instabilité locale du graphe. Puis nous nous intéressons au bien être global de l'économie dans le cas où les agents disposent d'une stratégie pour déterminer leurs liens sociaux et montrons en particulier, dans le cas ou les agents sont mortels, que la diversité des stratégies conduit à un accroissement du bien être collectif

Economy-driven Shaping of Social Networks and Emerging Class Behaviors

International audienceIn this paper, we propose an agent-based analysis of a cumulative social-network game. Agents grant loans to their neighbours to maximize their intertemporal utility function. With a complete graph, we show that interest rates converge toward the theoretical equilibrium, even if ther is no centralized walrasian auctioneer and no preference transmition between agents. With a dynamic network, we explain why the network can't stabilize with a rational strategy. We introduce death and show that, even if the rational strategy is individually the best, the situation where three different strategies coexist is better for the global welfare

Negotiation protocols and dynamic social networks

International audienceMulti-agent system make it possible to investigate systems with complex interaction protocols and limited information sharing. Our objective in this paper is to emphasize the impact of exchange protocols in social networks. The presented MAS considers a loan-granting scenario where each agent can borrow/lend money to its neighbors and/or consume it. We define six interaction protocols, ranging from fixed equilibrium rate loans to double-free auctions, and we study their impact on the network structure and the global welfare of the economy. Further, the agent fitness is investigated in relation with its connectivity (number of neighbors) and eccentricity (longest path to the other agents)

Adaptive Operator Selection and Management in Evolutionary Algorithms

One of the settings that most affect the performance of Evolutionary Algorithms is the selection of the variation operators that are efficient to solve the problem at hand. The control of these operators can be handled in an autonomous way, while solving the problem, at two different levels: at the structural level, when deciding which operators should be part of the algorithmic framework, referred to as Adaptive Operator Management (AOM); and at the behavioral level, when selecting which of the available operators should be applied at a given time instant, called as Adaptive Operator Selection (AOS). Both controllers guide their choices based on a common knowledge about the recent performance of each operator. In this chapter, we present methods for these two complementary aspects of operator control, the ExCoDyMAB AOS and the Blacksmith AOM, providing case studies to analyze them in order to highlight the major issues that should be considered for the design of more autonomous Evolutionary Algorithms