Emma Jonson

Impacts on Stability of Interdependencies Between Markets in a Cobweb Model

We present a cobweb model of interdependent markets on both the supply and demand sides and apply it to a food and bioenergy framework. The supply side is represented by an agent based model of global land use while the consumer side consists of interlinked demand functions. We find that the two kinds of interdependencies have opposing effects. Linking markets on the supply side transfers instabilities within the system and may cause price fluctuations in previously stable markets. Market interdependency on the demand side, on the other hand, has a stabilizing effect.

Projection Of A Heterogenous Agent-Based Production Economy Model To A Closed Dynamics Of Aggregate Variables

A model framework that describes a simple production economy is presented, in which the micro-dynamics can be projected to a closed dynamics of aggregate variables. The construction is based on an agent-based model with heterogeneity both regarding production characteristics and the strategies agents use to predict future prices as a basis for choosing what to produce. The world is divided into a number of regional markets that collect the locally produced goods and via inter-market trade supply regional demands with goods. We discuss the model features that make it possible to project the agent-based micro-dynamics to a closed form dynamics on the level of regionally aggregate quantities. One advantage of such a projection from a high dimensional agent-based dynamics to a low dimensional dynamical system is that the stability characteristics can be analytically approached, and this is illustrated by a derived condition for when a mix of naive and rational agents can stabilize the system. Some illustrations of the general framework in a model of global agricultural land-use are also given.