4 th World Congress of Social Simulation, TAIPEI, 2012 Special Session: Applications of Social Simulation in Politics and Public Spheres Macroeconomic forecasting with agent-based models. Prediction and simulation of the impact of public policies on SMEs.

The aim of this paper is to show and discuss an integrated scheme of the MOSIPS project. This project, under an agent-based model methodology, focuses on simulating and evaluating policies for small and medium enterprises within a local environment. Its purpose is to conduct experiments on the implementation of policies according to different socio-economic scenarios. The results of these experiments allow stakeholders and citizens knowing how the measures proposed by governments affect them and enable them to interact in the decision-making process by relying on first-hand information. Participation through social networks reinforces this interaction. This perspective allows analyzing and implementing the actions, interactions and results between agents. At the micro-level, the model provides two main kinds of agents: individuals and firms, and some other entities: the public sector, the financial system, and the external sector. It also determines rules for actions and interactions. Simulations on variables and parameters lead to the analysis of the evolution and the forecast of the system at the macroeconomic-level. The trajectories of the agents offer a dynamic standpoint that overcomes the standard equilibrium models. All this process drives to complex models, even long term, through the successive performance by individuals and firms, in each period, of the short-term models. Thus, the behavior of the model in the long-term becomes the update, period by period, of the trajectories followed by the agents in the short-term models.