The need for people to keep their genetic data confidential is crucial to help exploit medical advances, a key British Committee believes. Nigel Williams reports.

Decisions or inferences sometimes have to made in situations where substantive information about aspects of the problem are either lacking or conflicting. This is often handled by constructing a non-informative prior by appealing to principles such as indifference, maximum entropy, invariance, or maximizing missing information. Unfortunately these priors and the resulting posteriors may depend ...

We introduce and motivate a non-standard multi-modal logic to represent and reason about ignorance in Multi-Agent Systems. We argue that in Multi-agent systems being able to reason about what agents ignore is just as important as being able to reason about what agents know. We show a sound and complete axiomatisation for the logic. We investigate its applicability by restating the feasibility c...

An individual (the leader) with free access to information decides how much public evidence to collect. Conditional on this information, another individual with conflicting preferences (the follower) undertakes an action that affects the payoff of both players. In this game of incomplete but symmetric information, we characterize the rents obtained by the leader due to his control of the genera...

It is commonly-accepted wisdom that more information is better, and that information should never be ignored. Here we argue, using both a Bayesian and a non-Bayesian analysis, that in some situations you are better off ignoring information if your uncertainty is represented by a set of probability measures. These include situations in which the information is relevant for the prediction task at...

A decision maker (DM) makes choices from different sets of alternatives. The DM is initially fully ignorant of the payoff associated to each alternative, and learns these payoffs only after a large number of choices have been made. We show that, in the presence of an outside option once payoffs are learned, the optimal choice rule from sets of alternatives is one that is as if the DM had strict...

In several papers, John Norton has argued that Bayesianism cannot handle ignorance adequately due to its inability to distinguish between neutral and disconfirming evidence. He argued that this inability sows confusion in, e.g., anthropic reasoning in cosmology or the Doomsday argument, by allowing one to draw unwarranted conclusions from a lack of knowledge. Norton has suggested criteria for a...

The veil of ignorance has been used often as a tool for recommending what justice requires with respect to the distribution of wealth. We complete Harsanyi’s model of the veil of ignorance by appending information permitting interpersonal comparability of welfare. We show that the veil-of-ignorance conception of John Harsanyi, so completed, and Ronald Dworkin’s, when modeled formally, recommend...

This paper aims to develop an analysis of how ignorance affects the reasoning activity and is related to the concept of uncertainty. With reference to a simple inferential reasoning step, involving a single piece of relational knowledge, we identify four types of ignorance and show how they give rise to different types of uncertainty. We then introduce the concept of reasoning attitude, as a ba...