Can children resist making interpretations when uncertain?

In two experiments we examined young children’s ability to delay a response to ambiguous input. In Experiment 1 5- and 6- year olds performed as poorly when they had to choose between basing an interpretation on ambiguous input and delaying an interpretation as when making explicit evaluations of knowledge. Seven- and 8- year olds’ found the former task easy. In Experiment 2 5- and 6- year olds performed well on a task that required delaying a response but removed the need to decide between strategies. We discuss children’s difficulty with ambiguity in terms of the decision making demands made by different procedures. These demands appear to cause particular problems for young children

Anytime Computation of Cautious Consequences in Answer Set Programming

Query answering in Answer Set Programming (ASP) is usually solved by computing (a subset of) the cautious consequences of a logic program. This task is computationally very hard, and there are programs for which computing cautious consequences is not viable in reasonable time. However, current ASP solvers produce the (whole) set of cautious consequences only at the end of their computation. This paper reports on strategies for computing cautious consequences, also introducing anytime algorithms able to produce sound answers during the computation.Comment: To appear in Theory and Practice of Logic Programmin

From fly-by-wire to drive-by-wire: Safety implications of automation in vehicles

The purpose of this paper is to critically review the current trend in automobile engineering toward automation of many of the functions previously performed by the driver. Working on the assumption that automation in aviation represents the basic model for driver automation, the costs and benefits of automation in aviation are explored as a means of establishing where automation of drivers' tasks are likely to yield benefits. It is concluded that there are areas where automation can provide benefits to the driver, but there are other areas where this is unlikely to be the case. Automation per se does not guarantee success, and therefore it becomes vital to involve Human Factors into design to identify where automation of driver functions can be allocated with a beneficial outcome for driving performance

An Architectural Approach to Ensuring Consistency in Hierarchical Execution

Hierarchical task decomposition is a method used in many agent systems to organize agent knowledge. This work shows how the combination of a hierarchy and persistent assertions of knowledge can lead to difficulty in maintaining logical consistency in asserted knowledge. We explore the problematic consequences of persistent assumptions in the reasoning process and introduce novel potential solutions. Having implemented one of the possible solutions, Dynamic Hierarchical Justification, its effectiveness is demonstrated with an empirical analysis

Uncertainty in Multi-Commodity Routing Networks: When does it help?

We study the equilibrium behavior in a multi-commodity selfish routing game with many types of uncertain users where each user over- or under-estimates their congestion costs by a multiplicative factor. Surprisingly, we find that uncertainties in different directions have qualitatively distinct impacts on equilibria. Namely, contrary to the usual notion that uncertainty increases inefficiencies, network congestion actually decreases when users over-estimate their costs. On the other hand, under-estimation of costs leads to increased congestion. We apply these results to urban transportation networks, where drivers have different estimates about the cost of congestion. In light of the dynamic pricing policies aimed at tackling congestion, our results indicate that users' perception of these prices can significantly impact the policy's efficacy, and "caution in the face of uncertainty" leads to favorable network conditions.Comment: Currently under revie

The Moral Grounds of Reasonably Mistaken Self-Defense

Some, but not all, of the mistakes a person makes when acting in apparently necessary self-defense are reasonable: we take them not to violate the rights of the apparent aggressor. I argue that this is explained by duties grounded in agents' entitlements to a fair distribution of the risk of suffering unjust harm. I suggest that the content of these duties is filled in by a social signaling norm, and offer some moral constraints on the form such a norm can take

The reform of the NHS in Portugal

The objective of this article is to describe the Portuguese National Healthcare Service, giving a special emphasis to the recent reforms that have been introduced since the beginning of 2002. Its main argument is that there are two different (but connected) rationales that underpin the orientation of the current reforms. One the one hand, the explicit rationale that refers mainly to the ‘visible’ and stated causes and motivations of the reforms. On the other hand, the implicit rationale, whose influence over the government’s actions is not expressed as such, either because it is not perceived, or because it is not assumed. For this purpose, it is essential to start by giving an historical account of how the NHS started in Portugal and in which direction it has been evolving in the last four decades. This section has particular interest considering that it gives meaning, together with other arguments, to the implicit rationale, to the extent that the current reforms are product of the historical context in which the NHS was created and its subsequent developments. In the second part, the focus is on the reformation period, that started in 2002 and that is still going on at the moment. The main reforms that are being conducted are analysed, being this section mainly of a descriptive nature. What is considered to be important in this section is to give the government’s account of the reforms, in order to make clear what are its motivations and its goals. Furthermore, by doing this analysis it makes it possible to put forward what is meant by explicit rationale and identify its features. In section three, the reforms described in section two are analysed individually in a critical way. The objective of this section is to ‘make sense’ of the reforms being undertaken by the government and consider some aspects that are still unclear and that need further reflection. It is throughout this section that the main argument of this article is explored, by discussing, when applicable, what is the rationale underpinning the different reforms