A Short Introduction to Model Selection, Kolmogorov Complexity and Minimum Description Length (MDL)

The concept of overfitting in model selection is explained and demonstrated with an example. After providing some background information on information theory and Kolmogorov complexity, we provide a short explanation of Minimum Description Length and error minimization. We conclude with a discussion of the typical features of overfitting in model selection.Comment: 20 pages, Chapter 1 of The Paradox of Overfitting, Master's thesis, Rijksuniversiteit Groningen, 200

Convergence of Income Growth Rates in Evolutionary Agent-Based Economics

We consider a heterogeneous agent-based economic model where economic agents have strictly bounded rationality and where income allocation strategies evolve through selective imitation. Income is calculated by a Cobb-Douglas type production function, and selection of strategies for imitation depends on the income growth rate they generate. We show that under these conditions, when an agent adopts a new strategy, the effect on its income growth rate is immediately visible to other agents, which allows a group of imitating agents to quickly adapt their strategies when needed.Comment: 5 pages, 2 figure

Costs and benefits of tuning parameters of evolutionary algorithms

Abstract. We present an empirical study on the impact of different design choices on the performance of an evolutionary algorithm (EA). Four EA components are considered—parent selection, survivor selection, recombination and mutation—and for each component we study the impact of choosing the right operator and of tuning its free parameter(s). We tune 120 different combinations of EA operators to 4 different classes of fitness landscapes and measure the cost of tuning. We find that components differ greatly in importance. Typically the choice of operator for parent selection has the greatest impact, and mutation needs the most tuning. Regarding individual EAs however, the impact of design choices for one component depends on the choices for other components, as well as on the available amount of resources for tuning.

Design, modelling and control of a novel agricultural robot with interlock drive system

A current problem in the design of small and lightweight autonomous agricultural robots is how to create sufficient traction on soil to pull an agricultural implement or load. One promising solution is offered by the interlock drive system, which penetrates spikes into the soil to create traction. The combination of soil penetrating spikes and a push-pull design offers new possibilities for vehicle control. By controlling the interlocking of the spikes and pushing and pulling them against the main frame, the vehicle can perform tight maneuvers. To validate this idea, we designed a robot, capable of creating high traction and performing headland turns. The navigation of the new robot system is performed by actively pushing the spikes, mounted on a slide into the soil, while the main frame is pushed back and pulled forward. The vehicle of 2-meter length was able to turn on the spot, and could follow a straight line, just using the spikes and the push-pull mechanism. The trajectory and the performed measurements suggest, that a vehicle which uses only spikes for traction and steering is fully capable of performing autonomous tasks in agriculture fields

Evolutionary Analysis of Climate Policy and Renewable Energy: Heterogeneous Agents, Relative Welfare and Social Network

We demonstrate how an evolutionary agent-based model can be used to evaluate climate policies that take the heterogeneity of strategies of individual agents into account. An essential feature of the model is that the fitness of an economic strategy is determined by the relative welfare of the associated agent as compared to its immediate neighbors in a social network. This enables the study of policies that affect relative positions of individuals. We formulate two innovative climate policies, namely `prizes', altering directly relative welfare, and `advertisement', which influences the social network of interactions. The policies are illustrated using a simple model of global warming where a resource with a negative environmental impact---fossil energy---can be replaced by an environmentally neutral yet less cost effective alternative, namely renewable energy. It is shown that the general approach enlarges the scope of economic policy analysis

Evolutionary Analysis of Climate Policy and Renewable Energy: Heterogeneous Agents, Relative Welfare and Social Network

We demonstrate how an evolutionary agent-based model can be used to evaluate climate policies that take the heterogeneity of strategies of individual agents into account. An essential feature of the model is that the fitness of an economic strategy is determined by the relative welfare of the associated agent as compared to its immediate neighbors in a social network. This enables the study of policies that affect relative positions of individuals. We formulate two innovative climate policies, namely `prizes', altering directly relative welfare, and `advertisement', which influences the social network of interactions. The policies are illustrated using a simple model of global warming where a resource with a negative environmental impact---fossil energy---can be replaced by an environmentally neutral yet less cost effective alternative, namely renewable energy. It is shown that the general approach enlarges the scope of economic policy analysis

Evolutionary Analysis of Climate Policy and Renewable Energy: Heterogeneous Agents, Relative Welfare and Social Network

We demonstrate how an evolutionary agent-based model can be used to evaluate climate policies that take the heterogeneity of strategies of individual agents into account. An essential feature of the model is that the fitness of an economic strategy is determined by the relative welfare of the associated agent as compared to its immediate neighbors in a social network. This enables the study of policies that affect relative positions of individuals. We formulate two innovative climate policies, namely a prize, altering directly relative welfare, and advertisement, which influences the social network of interactions. The policies are illustrated using a simple model of global warming where a resource with a negative environmental impact—fossil energy—can be replaced by an environmentally neutral yet less cost-effective alternative, namely renewable energy. It is shown that the general approach enlarges the scope of economic policy analysis

Evolutionary Analysis of Climate Policy and Renewable Energy: Heterogeneous Agents, Relative Welfare and Social Network

We demonstrate how an evolutionary agent-based model can be used to evaluate climate policies that take the heterogeneity of strategies of individual agents into account. An essential feature of the model is that the fitness of an economic strategy is determined by the relative welfare of the associated agent as compared to its immediate neighbors in a social network. This enables the study of policies that affect relative positions of individuals. We formulate two innovative climate policies, namely a prize, altering directly relative welfare, and advertisement, which influences the social network of interactions. The policies are illustrated using a simple model of global warming where a resource with a negative environmental impact—fossil energy—can be replaced by an environmentally neutral yet less cost-effective alternative, namely renewable energy. It is shown that the general approach enlarges the scope of economic policy analysis