Information can kill

Recent advances in understanding links between genes and the susceptibility to particular diseases have considerably increased the scope for predictive diagnosis. Methods. We analyse how the introduc- tion of predictive diagnosis affects patients�decisions to undergo medical screenings relying on a �rational choice�model. Findings. We show that predictive diagnosis can increase the number of fatalities from a deadly disease. Interpretation. Our result shows the necessity of careful further analysis and debate about the pros and cons of predictive diagnosis and the publication of medical research in general

Group reputations: an experimental foray

Often information structures are such that while individual reputation building is impossible groups of agents would have the opportunity of building up a reputation. We experimentally examine whether groups of sellers in markets that suffer from moral hazard are able to build up reputations and, thus, avoid market breakdown. We contrast our findings with situations where sellers alternatively can build up an individual reputation or where there are no possibilities for reputation building at all. Our results offer a rather optimistic outlook on group reputations. Even though sellers only receive some of the reputation benefits of withstanding short-run incentives to exploit trust, they are able to overcome the dilemma and successfully exploit the information structure

Reciprocal Strategies and Aspiration Levels in a Cournot-Stackelberg Experiment

We examine behavior in Cournot and Stackelberg markets in a simple experiment where participants experience both market forms. Moreover, Stackelberg followers have to submit full response strategies. Our main finding is that Stackelberg followers employ rather flat, reciprocal response function, i.e., they punish leaders in who try to exploit their strategic adavantage and are willing to cooperate with cooperative leaders. Also, it turns out that prior exposure to a symmetric market makes followers more aggressive which hints at the role of aspiration levels in markets

Public statistics and private experience: varying feedback information in a take or pass game

We study how subjects in an experiment use different forms of public information about their opponents’ past behaviour. In the absence of public information, subjects appear to use rather detailed statistics summarizing their private experiences. If they have additional public information, they make use of this information even if it is less precise than their own private statistics–except for very high stakes. Making public information more precise has two consequences: It is also used when the stakes are very high and it reduces the number of subjects who ignore any information–public and private. That is, precise public information crowds in the use of own information. Finally, our results shed some light on unravelling in centipede games

Dogville or an illustration of some properties of general equilibrium

Lars von Trier's movie 'Dogville' illustrates some illuminating and poignant comparative statics of equilibrium allocations, according to Heike Harmgart and Steffen Huck

Players with limited memory

This paper studies a model of memory. The model takes into account that memory capacity is limited and imperfect. We study how agents with such memory limitations, who have very little information about their choice environment, play games. We introduce the notion of a Limited Memory Equilibrium (LME) and show that play converges to an LME in every generic normal form game. Our characterization of the set of LME suggests that players with limited memory do (weakly) better in games than in decision problems. We also show that agents can do quite well even with severely limited memory, although severe limitations tend to make them behave cautiously

Endogenous leadership in teams

In this paper we study the mechanics of “leading by example” in teams. Leadership is beneficial for the entire team when agents are conformists, i.e., dislike effort differentials. We also show how leadership can arise endogenously and discuss what type of leader benefits a team most

Comparison of two sampling protocols and four home-range estimators using radio-tracking data from urban badgers Meles meles

Radio-telemetry is often the method of choice for studies of species whose behaviour is difficult to observe directly. However, considerable debate has ensued about the best way of deriving home-range estimates. In recent years, kernel estimators have become the most widely used method, together with the oldest and simplest method, the minimum convex polygon (MCP). More recently, it has been suggested that the local convex hull (LCH) might be more appropriate than kernel methods in cases where an animal’s home range includes a priori inaccessible areas. Yet another method, the Brownian bridge (BB), explicitly uses autocorrelated data to determine movement paths and, ultimately, home ranges or migration routes of animals. Whereas several studies have used simulation techniques to compare these different methods, few have used data from real animals. We used radio-telemetric data from urban badgers Meles meles to compare two sampling protocols (10-minute vs at least 30-minute inter-fix intervals) and four home-range estimators (MCP, fixed kernels (FK), LCH and BB). We used a multi-response permutation procedure and randomisation tests to compare overall patterns of fixes and degree of overlap of home ranges estimated using data from different sampling protocols, and a general linear model to compare the influence of sampling protocols and home-range estimator on the size of habitat patches. The shape of the estimated home ranges was influenced by sampling protocol in some cases. By contrast, the sizes and proportions of different habitats within home ranges were influenced by estimator type but not by sampling protocol. LCH performed consistently better than FK, and is especially appropriate for patchy study areas containing frequent no-go zones. However, we recommend using LCH in combination with other methods to estimate total range size, because LCH tended to produce smaller estimates than any other method. Results relating to BB are preliminary but suggest that this method is unsuitable for species in which range size is small compared to average travel speed.Marie-Curie Intra-European Fellowship (BSSUB - 24007); Defra WSC contract WM0304; Wildlife Biology granted the permit to upload the article to this repositor

More order with less law: on contract enforcement, trust, and crowding

Most contracts, whether between voters and politicians or between house owners and contractors, are incomplete. “More law,” it typically is assumed, increases the likelihood of contract performance by increasing the probability of enforcement and/or the cost of breach. We examine a contractual relationship in which the first mover has to decide whether she wants to enter a contract without knowing whether the second mover will perform. We analyze how contract enforceability affects individual performance for exogenous preferences. Then we apply a dynamic model of preference adaptation and find that economic incentives have a nonmonotonic effect on behavior. Individuals perform a contract when enforcement is strong or weak but not with medium enforcement probabilities: Trustworthiness is “crowded in” with weak and “crowded out” with medium enforcement. In a laboratory experiment we test our model’s implications and find support for the crowding prediction. Our finding is in line with the recent work on the role of contract enforcement and trust in formerly Communist countries

Local Control: An Educational Model of Private Enforcement of Public Rules

We study a society of agents where individual incentives conflict with collective ones and thus individual utility maximization leads to inefficient outcomes. We assume that there is no functioning central institution which can control individual behavior. Instead, we analyze a system of what we call local control (LC), where the enforcement of punishment lies in the hands of individuals in the society rather than in the hand of a central institution. The mechanism that governs the spread of control is the educational impact on an agent being controlled by some other agent, where we distinguish between executed and threatened punishment. Agents maximize their payoffs and underlie a constant drift towards not controlling others anymore. Our main results show that LC can survive if the educational impact of control is strong enough relative to the drift. If the educational impact of control is too weak LC breaks down. Moreover, there exists a non{monotonic punishment effect that sets a trap for standard legal policy advices.cooperation;prisoner's dilemma;social control;punishment;institutional change