Commonsense reasoning is different. We often draw plausible conclusions based on the assumption that the world in which we function and about which we reason is normal and as expected. This is far from being irrational. To the contrary, it is the best we can do in situations in which we have only incomplete information. However, as unexpected as it may be, it can happen that our normality assum...

We present a formal characterization and semantic representation for a number of credulous inference relations based on the notion of a,n epistemic state. It is shown, in particular, that credulous inference can be naturally represented in terms of expectations (see [Gardenfors and Makinson, 1994]). We describe also the relationships between credulous and usual skeptical nonmonotonic inference ...

The present paper deals with strong-monotonic, monotonic and weak-monotonic language learning from positive and negative examples. The three notions of monotonicity re ect di erent formalizations of the requirement that the learner has to produce always better and better generalizations when fed more and more data on the concept to be learnt. We characterize strong-monotonic, monotonic, weak-mo...

Creative search trajectories are chronologically organized intermediate products (such as sketches and drafts) from the creative process. We discuss what sorts of conclusions can be made when these trajectories show non-monotonic progress toward the final creation. We introduce several key distinctions that are often overlooked, and argue that two null hypothesis processes must be rejected befo...

This paper analyzes the market for financial information and the incentive of institutions, such as Reuters, to provide information to traders in decentralized financial markets. We derive the following results. (i) The optimal selling strategy consists of selling identical information (Reuters’ screen) to all traders. (ii) The traders buy information from the same providers. If the traders may...

Our purpose is to exhibit a modular systematic method of representing non{ monotonic reasoning problems with the Well Founded Semantics WFS of extended logic programs augmented with eXplicit negation (WFSX), augmented by its Contradiction Removal Semantics (CRSX) when needed. We apply this semantics, and its contradiction removal semantics counterpart, to represent non-monotonic reasoning probl...

This paper analyzes all-pay auctions where the bidders have affiliated values for the object for sale and where the signals take binary values. Since signals are correlated, high signals indicate a high degree of competition in the auction and since even losing bidders must pay their bid, non-monotonic equilibria arise. We show that the game has a unique symmetric equilibrium, and that whenever...

I study a budget-constrained, private-valuation, sealed-bid sequential auction with two incompletely-informed, risk-neutral bidders in which the valuations and income may be non-monotonic functions of a bidder’s type. Parameters permit the existence of multiple equilibrium symmetric bidding functions that differ in allocation, efficiency and revenue. The sequence of sale affects the competition...

In probabilistics reasoning at optimum entropy ME reasoning has proved to be a most sound and consistent method for inference This paper investigates its properties in the framework of nonmonotonic reasoning In particular we show that ME reasoning satis es cumulativity and loop and we focus on its connection to conditionals Finally we intro duce the notion of a universal inference operation to ...

Intentional reasoning is also logical reasoning. Since it is a dynamic process that involves reasoning from beliefs, goals and time, it requires both a temporal semantics and a non-monotonic behavior. In this work we propose a model of intentional reasoning as a case of nonmonotonic reasoning. We also show the consistency and soundness of the system.