Efficiency of competition in insurance markets with adverse selection

There is a general presumption that competition is a good thing. In this paper we show that competition in the insurance markets can be bad when there is adverse selection. Using the dual theory of choice under risk, we are able to fully characterize both the competitive and the monopoly market outcomes. When there are two types of risk, the monopoly dominates competition if and only if competition leads to market unravelling. When there are a continuum of types the efficiency of competition is less trivial. In effect monopoly is shown to provide better insurance but at the cost of driving out some agents from the market. Performing simulation for different distributions of risk, we find that monopoly in general performs (much) better than competition in terms of the realization of the gains from trade across all traders in equilibrium. The reason is that the monopolist can exploit its market power to relax the incentive constraints

GOAL-DTU: Development of Distributed Intelligence for the Multi-Agent Programming Contest

We provide a brief description of the GOAL-DTU system for the agent contest, including the overall strategy and how the system is designed to apply this strategy. Our agents are implemented using the GOAL programming language. We evaluate the performance of our agents for the contest, and finally also discuss how to improve the system based on analysis of its strengths and weaknesses.Comment: 28 pages, 45 figure

Agent Programming with Declarative Goals

A long and lasting problem in agent research has been to close the gap between agent logics and agent programming frameworks. The main reason for this problem of establishing a link between agent logics and agent programming frameworks is identified and explained by the fact that agent programming frameworks have not incorporated the concept of a `declarative goal'. Instead, such frameworks have focused mainly on plans or `goals-to-do' instead of the end goals to be realised which are also called `goals-to-be'. In this paper, a new programming language called GOAL is introduced which incorporates such declarative goals. The notion of a `commitment strategy' - one of the main theoretical insights due to agent logics, which explains the relation between beliefs and goals - is used to construct a computational semantics for GOAL. Finally, a proof theory for proving properties of GOAL agents is introduced. Thus, we offer a complete theory of agent programming in the sense that our theory provides both for a programming framework and a programming logic for such agents. An example program is proven correct by using this programming logic

Programming Deliberation Strategies in Meta-APL

A key advantage of BDI-based agent programming is that agents can deliberate about which course of action to adopt to achieve a goal or respond to an event. However, while state-of-the-art BDI-based agent programming languages provide flexible support for expressing plans, they are typically limited to a single, hard-coded, deliberation strategy (perhaps with some parameterisation) for all task environments. In this paper, we present an alternative approach. We show how both agent programs and the agent’s deliberation strategy can be encoded in the agent programming language meta-APL. Key steps in the execution cycle of meta-APL are reflected in the state of the agent and can be queried and updated by meta-APL rules, allowing BDI deliberation strategies to be programmed with ease. To illustrate the flexibility of meta-APL, we show how three typical BDI deliberation strategies can be programmed using meta-APL rules. We then show how meta-APL can used to program a novel adaptive deliberation strategy that avoids interference between intentions

Institutions and Functions

What is an institution? And what distinguishes one type of institution from another? We answer these questions using a functionalist approach: types of institutions are identified by their function, or the coordination problems they solve; token institutions are specific solutions to these problems, or equilibria of strategic games. The functionalist approach provides some insights into the limits of reform, or the extent to which institutions \u2013 like marriage, property, or democracy \u2013 can be modified without turning them into entities of a different kind