We argue that in extensive decision problems (extensive games with a single player) with imperfect recall care must be taken in interpreting information sets and strategies. Alternative interpretations allow for different kinds of analysis. We address the following issues: 1. randomization at information sets; 2. consistent beliefs; 3. time consistency of optimal plans; 4. the multiselves approach to decision making. We illustrate our discussion through an example that we call the ‘‘paradox of the absentminded driver.’’ Journal of Economic (...) Literature Classification Numbers: C7, D0. 1997 Academic Press. (shrink)

I will show that the semantic structure of a new imperfect-information propositional logic can be described in terms of extensive forms of semantic games. I will discuss some ensuing properties of these games such as imperfect recall, informational consistency, and team playing. Finally, I will suggest a couple of applications that arise in physics, and most notably in quantum theory and quantum logics.

We present a variant of ATL with incomplete information which includes the distributed knowledge operators corresponding to synchronous action and perfect recall. The cooperation modalities assume the use the distributed knowledge of coalitions and accordingly refer to perfect recall incomplete information strategies. We propose a model-checking algorithm for the logic. It is based on techniques for games with imperfect information and partially observable objectives, and involves deciding emptiness for automata on infinite trees. We also propose an axiomatic (...) system and prove its completeness for a rather expressive subset. As for the constructs left outside this completely axiomatised subset, we present axioms by which they can be defined in the subset on the class of models in which every state has finitely many successors and give a complete axiomatisation for a “flat” subset of the logic with these constructs included. (shrink)

Should we doubt the exactness of the predictive quantum rules of calculation? Although this question is sometimes raised in connection with the one on how to physically understand quantum mechanics, these two questions should not be mixed up. It is recalled here that even the first one is stil an object of controversy, and it is shown (a) that in one specific case the arguments put forward in support of such doubts are hardly cogent but (b) that, nevertheless, at least (...) in one specific other context, the question is worth attention. This is the problem of repeated imperfect measurements. Relative to it, a theoretical possibility is shown of discriminating between the thesis that the quantum rules are exact and a powerful theory of which it is proved that it cannot be reconciled with the assumption. (shrink)

In order to predict and explain behavior, one cannot specify the mental state of an agent merely by saying what information she possesses. Instead one must specify what information is available to an agent relative to various purposes. Specifying mental states in this way allows us to accommodate cases of imperfect recall, cognitive accomplishments involved in logical deduction, the mental states of confused or fragmented subjects, and the difference between propositional knowledge and know-how .

_Anthropic Bias_ explores how to reason when you suspect that your evidence is biased by "observation selection effects"--that is, evidence that has been filtered by the precondition that there be some suitably positioned observer to "have" the evidence. This conundrum--sometimes alluded to as "the anthropic principle," "self-locating belief," or "indexical information"--turns out to be a surprisingly perplexing and intellectually stimulating challenge, one abounding with important implications for many areas in science and philosophy. There are the philosophical thought experiments and paradoxes: (...) the Doomsday Argument; Sleeping Beauty; the Presumptuous Philosopher; Adam & Eve; the Absent-Minded Driver; the Shooting Room. And there are the applications in contemporary science: cosmology ; evolutionary theory ; the problem of time's arrow ; quantum physics ; game-theory problems with imperfect recall ; even traffic analysis. _Anthropic Bias_ argues that the same principles are at work across all these domains. And it offers a synthesis: a mathematically explicit theory of observation selection effects that attempts to meet scientific needs while steering clear of philosophical paradox. (shrink)

from now on , was to point out that the model commonly used to describe . a decision problem with imperfect recall suffers from major ambiguities in its interpretation. We claimed that several issues which were immaterial in decision problems with perfect recall may be of importance in the analysis of decision problems with imperfect recall. The issues that we raised can be summarized by the following questions.

The Doomsday argument purports to show that the risk of the human species going extinct soon has been systematically underestimated. This argument has something in common with controversial forms of reasoning in other areas, including: game theoretic problems with imperfect recall, the methodology of cosmology, the epistemology of indexical belief, and the debate over so-called fine-tuning arguments for the design hypothesis. The common denominator is a certain premiss: the Self-Sampling Assumption. We present two strands of argument in favor (...) of this assumption. Through a series of thought experiments we then investigate some bizarre prima facie consequences – backward causation, psychic powers, and an apparent conflict with the Principal Principle. (shrink)

Empirical studies in business ethics often rely on self-reported data, but this reliance is open to criticism. Responses to questionnaires and interviews may be influenced by the subject's view of what the researcher might want to hear, by a reluctance to talk about sensitive ethical issues, and by imperfect recall. This paper reviews the extent to which published research in business ethics relies on interviews and questionnaires, and then explores the possibilities of using secondary data, such as company (...) documents and newspaper reports, as a source for empirical studies in applied ethics. A specific example is then discussed, describing the source material, the method, the development of the research questions, and the way in which reliability and validity were established. In the example, content analysis was used to examine the extent to which the executive virtue of courage was observed or called for in items published in four international daily newspapers, and to explore the meaning which was attributed to "courage" in the papers. (shrink)

In a stimulating paper, Piccione and Rubinstein (1997) argued how a decision maker could undertake dynamically inconsistent choices when, in an extensive form decision problem, she has a particular type of imperfect recall named absentmindedness. Such memory limitation obtains whenever information sets include decision histories along the same decision path. Starting from work focusing on the absentminded driver example, and independently developed by Segal (2000) and Dimitri (1999), the main theorem of this article provides a general result of (...) dynamically consistent choices, valid for a large class of finite extensive form decision problems without nature. (shrink)

If we express our knowledge in sentences, we will find that these sentences are linked in complex patterns governed by our observations and our inferences from these observations. These inferences are to a large extent driven by logical rules. We ask whether the structure logic imposes on our knowledge restricts what we forget and what we remember. The model is a two period S5 logic. In this logic, we propose a memory loss operator: the agent forgets a sentence pif and (...) only if he knows pat time 1 and he does not know pat time 2. Equipped with the operator, we prove theorems on the relation between knowledge and memory loss. The main results point to classes of formulas that an agent cannot forget, and classes of formulas he must forget. A desirable feature is that most results hold in the S4 logic. The results illustrate bounds to memory loss, and thus to bounded rationality. We apply the model to single-agent conventions: conventions made between an agent and himself. (shrink)

In this paper we study connections between game theoretical concepts and results, and features of IF-predicate logic, extending observations from J. van Benthem (2001) for IF-propositional logic. We highlight how both characteristics of perfect recall can fail in the semantic games for IF-formulas, and we discuss the four Thompson transformations in relation with IF-logic. Many (strong) equivalence schemes for IF-logic correspond to one or more of the transformations. However, we also find one equivalence that does not fit in this (...) picture, by the type of imperfect recall involved. We point out that the connection between the transformations and logical equivalence schemes is less direct in IF-first order logic than in the propositional case. The transformations do not generate a reduced normal form for IF-logic, because the IF-language is not flexible enough. (shrink)

Thirders sometimes feel compelled to give the same answer – a credence of 1/3 – to the original and the duplicating Sleeping Beauty problem, which leads to some unwanted consequences. I will argue that they do not have to feel compelled to give the same answer, because the original and the duplicating version of the Sleeping Beauty problem are different types of decision problems. If one accepts that it is rationally permissible to give different answers to different types of decision (...) problems, both versions do not require the same solution. (shrink)

An important approach to game theory is to examine the consequences of beliefs that rational agents may have about each other. This paper considers respect for public preferences. Consider an agent A who believes that B strictly prefers an option a to an option b. Then A respects B’s preference if A considers the choice of a “infinitely more likely” than the choice of B; equivalently, if A assigns probability 1 to the choice of a given that B chooses a (...) or b. Respect for public preferences requires that if it is common belief that B prefers a to b, then it is common belief that all other agents respect that preference. Along the lines of Blume, Brandenburger and Dekel [4] and Asheim [1], I treat respect for public preferences as a constraint on lexicographic probability systems. The main result is that if respect for public preferences and perfect recall obtains, then players choose in accordance with Iterated Backward Inference. Iterated Backward Inference is a procedure that generalizes standard backward induction reasoning for games of both perfect and imperfect information. From Asheim’s characterization of proper rationalizability [1] it follows that properly rationalizable strategies are consistent with respect for public preferences; hence strategies eliminated by Iterated Backward Inference are not properly rationalizable. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:17. HUME AND ABSTRACT GENERAL IDEAS In his discussion of abstract ideas in the Treatise, Hume offers what "...may... be thought... a plain dilemma, that decides concerning the nature of those abstract ideas..." He states the dilemma in these words: The abstract idea of a man represents men of all sizes and all qualities; which 'tis concluded it cannot do, but either by representing at once all possible sizes (...) and all possible qualities, or by representing no particular one at all. Now it having been esteemed absurd to defend the former proposition, as implying an infinite capacity in the mind, it has been commonly infer'd in favour of the latter; and our abstract ideas have been suppos'd to represent no particular degree either of quality or quantity. (T, 1,1,7,?.18) However, with respect to this dilemma, Hume says: But that this inference is erroneous, I shall endeavor to make appear, first, by proving, that 'tis utterly impossible to conceive any quantity or quality, without forming a precise notion of its degrees: And secondly by showing, that tho' the capacity of the mind be not infinite, yet we can at once form a notion of all possible degrees of quantity and quality, in such a manner at least, as, however imperfect, may serve all the purposes of reflexion and conversation. (T, 1,1,7, p. 18) The second item Hume claims he is about to prove is aimed at the first disjunct of the above-stated dilemma; more specifically, it is aimed at the claim that (1) An abstract idea (e.g., of a man) represents all possible degrees of quantity and quality (in men) only if the human mind is infinite in capacity. To show that (1) is false, Hume offers his own positive account of how ideas which are particular in nature may nevertheless be general in representation, even though the mind's capacity is finite. The first item Hume sets out to prove is aimed at the second disjunct, and conclusion, of the dilemma; it is aimed, that is, at 18. (2)Abstract ideas represent no particular degree of either quantity or quality. In this paper I will be concerned solely with Hume's attack on (2); it is this attack in which Hume says I "place my chief confidence." (T, I, I, 7, p. 24) I_ As stated, (2) is ambiguous, since it might be taken to mean that abstract ideas fail to represent altogether, or that they fail to represent any quantity or quality however construed. But, I believe, Hume means neither of these; he means, instead, that (2a) Abstract ideas represent non-particular, indeterminate degrees of quantity or quality. Now recall that Hume tries to refute (2a) by establishing, as he says, that (3)It is impossible to conceive any quantity or quality without forming a precise notion of its degrees. But how, by establishing (3), would Hume thereby refute or aid in the refutation of (2a)? And, for that matter, how does he support (3)? Hume's case for (3) consists of three arguments, the respective conclusions of which are most pertinent here. He concludes his first argument by saying that (4)...the general idea of a line...has in its appearance in the mind a precise degree of quantity and quality. (T, 1,1,7, p. 19) The conclusion of the second argument is this : (5)An idea is a weaker impression; and as a strong impression must necessarily have a determinate quantity and quality, the case must be the same with its copy or representative.(T, 1,1,7, p. 19) 19. and of the third it is this: (6)Abstract ideas are therefore in themselves individual, however they may become general in their representation. The image in the mind is only that of a particular object, tho' the application of it in our reasoning be the same, as if it were universal.(T, 1,1,7, p. 20) Construed in a fully general way, these conclusions assert that (7)Each idea is determinate with respect to öegree of) quantity and quality. But notice that (7) is not equivalent to, and does not obviously imply, (3). Hence, Hume... (shrink)

Software defects prediction at the initial period of the software development life cycle remains a critical and important assignment. Defect prediction and correctness leads to the assurance of the quality of software systems and has remained integral to study in the previous years. The quick forecast of imperfect or defective modules in software development can serve the development squad to use the existing assets competently and effectively to provide remarkable software products in a given short timeline. Hitherto, several researchers (...) have industrialized defect prediction models by utilizing statistical and machine learning techniques that are operative and effective approaches to pinpoint the defective modules. Tree family machine learning techniques are well-thought-out to be one of the finest and ordinarily used supervised learning methods. In this study, different tree family machine learning techniques are employed for software defect prediction using ten benchmark datasets. These techniques include Credal Decision Tree, Cost-Sensitive Decision Forest, Decision Stump, Forest by Penalizing Attributes, Hoeffding Tree, Decision Tree, Logistic Model Tree, Random Forest, Random Tree, and REP-Tree. Performance of each technique is evaluated using different measures, i.e., mean absolute error, relative absolute error, root mean squared error, root relative squared error, specificity, precision, recall, F-measure, G-measure, Matthew’s correlation coefficient, and accuracy. The overall outcomes of this paper suggested RF technique by producing best results in terms of reducing error rates as well as increasing accuracy on five datasets, i.e., AR3, PC1, PC2, PC3, and PC4. The average accuracy achieved by RF is 90.2238%. The comprehensive outcomes of this study can be used as a reference point for other researchers. Any assertion concerning the enhancement in prediction through any new model, technique, or framework can be benchmarked and verified. (shrink)

Excerpt from The Idea of Personality Not since the French Revolution have the masses of men had such a passionate trust in the power of ideas as they have today. Such ideas as society, state, person, are no longer the exclusive concern of the few favored experts in philosophy and political theory. Such other ideas as authority, responsibility, conscience, right, and freedom, have become more than the mere blunted foils of friendly, academic discussion. This democratization of ideas has been, on (...) the whole, a healthy stimulant. No one who recalls the riotous confusion of thought in the nineteenth century will regret a situation that seems to promise a period of redefinition. One does not have to be an obscurantist to regret the uncontrolled and, often uncritical way, in which the findings of physical science were applied in the fields of ethics, religion, politics, sociology, economics, and history. We should have been warned that speculation was moving too rapidly. The careful scientist rarely makes a sweeping and definite conclusion. More rarely still does he make a universal application of deductions, reached in his own sphere of investigation, to all branches of knowledge. If the philosophy of life, built upon the recent biological and sociological premises, has been unsatisfactory, this has been due to an apparent unwillingness to take the time required to distinguish what is of permanent value from what is simply the exaggeration of controversy, in the anxiety to establish a theory. It is conceivable that men should wish, under the impulse of fresh evidence, to re-examine their notions of God, the nature of human progress, society, and free-will; but it is not conceivable that conclusions, reached so rapidly and with so little discrimination between fact and hypothesis, should he always accurate and should really reflect life's problems and complexities. We need to be redeemed from our own overweening confidence. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works. (shrink)

Is capitalism inherently predatory? Must there be winners and losers? Is public interest outdated and free-riding rational? Is consumer choice the same as self-determination? Must bargainers abandon the no-harm principle? Prisoners of Reason recalls that classical liberal capitalism exalted the no-harm principle. Although imperfect and exclusionary, modern liberalism recognized individual human dignity alongside individuals' responsibility to respect others. Neoliberalism, by contrast, views life as ceaseless struggle. Agents vie for scarce resources in antagonistic competition in which every individual seeks dominance. (...) This political theory is codified in non-cooperative game theory; the neoliberal citizen and consumer is the strategic rational actor. Rational choice justifies ends irrespective of means. Money becomes the medium of all value. Solidarity and good will are invalidated. Relationships are conducted on a quid pro quo basis. However, agents can freely opt out of this cynical race to the bottom by embracing a more expansive range of coherent action. (shrink)

An important approach to game theory is to examine the consequences of beliefs that agents may have about each other. This paper investigates respect for public preferences. Consider an agent A who believes that B strictly prefers an option a to an option b. Then A respects B’s preference if A assigns probability 1 to the choice of a given that B chooses a or b. Respect for public preferences requires that if it is common belief that B prefers a (...) to b, then it is common belief that all other agents respect that preference. Along the lines of Blume, Brandenburger and Dekel [3] and Asheim [1], I treat respect for public preferences as a constraint on lexicographic probability systems. The main result is that given respect for public preferences and perfect recall, players choose in accordance with Iterated Backward Inference. Iterated Backward Inference is a procedure that generalizes standard backward induction reasoning for games of both perfect and imperfect information. From Asheim’s characterization of proper rationalizability [1] it follows that properly rationalizable strategies are consistent with respect for public preferences; hence strategies eliminated by Iterated Backward Inference are not properly rationalizable. (shrink)

The problem of the intuition of the individual as such, i. e. of its individuality (the „principle of individuation“) gave rise to many controversies. The problem becomes especially urgent in the light of the Christian revelation, since Christianity in the first place relates to the singular and individual (and therefore contingent), whereas the universal assumes only a secondary rôle. John Duns Scotus deals with this theologico-philosophical problem and sets out to defend intellective intuition of the individual as a whole. He (...) distinguishes three kinds within this type of cognition: perfect intuitive intellective cognition which is possible only in patria, direct but imperfect (i. e. not penetrating the principle of individuation) intuitive intellective cognition which relates to contingent truths and spiritual acts, and, finally, imperfect and indirect intuitive intellective cognition, i. e. acts of recalling the past intuitive cognitions. In these three examples the fundamental Scotus’s arguments are exhibited and the extent to which Scotus transgresses the limits of Aristotelian epistemology is made clear. (shrink)

This rigorous work critically examines the progressive consequentialist imperative to leave the world in better shape than they found it. Exploring moral theory and practical ethics, the book makes an important contribution to the rapidly expanding study of less demanding forms of consequentialism that do not require optimally good outcomes.

We analyse the two definitions of generalized quantifiers for logics of dependence and independence that have been proposed by F. Engström, comparing them with a more general, higher order definition of team quantifier. We show that Engström’s definitions can be identified, by means of appropriate lifts, with special classes of team quantifiers. We point out that the new team quantifiers express a quantitative and a qualitative component, while Engström’s quantifiers only range over the latter. We further argue that Engström’s definitions (...) are just embeddings of the first-order generalized quantifiers into team semantics, and fail to capture an adequate notion of team-theoretical generalized quantifier, save for the special cases in which the quantifiers are applied to flat formulas. We also raise several doubts concerning the meaningfulness of the monotone/nonmonotone distinction in this context. In the appendix we develop some proof theory for Engström’s quantifiers. (shrink)

Book description: The capacity to represent and think about time is one of the most fundamental and least understood aspects of human cognition and consciousness. This book throws new light on central issues in the study of the mind by uniting, for the first time, psychological and philosophical approaches dealing with the connection between temporal representation and memory. Fifteen specially written essays by leading psychologists and philosophers investigate the way in which time is represented in memory, and the role memory (...) plays in our ability to reason about time. They offer insights into current theories of memory processes and of the mechanisms and cognitive abilities underlying temporal judgements, and draw out fundamental issues concerning the phenomenology and epistemology of memory and our understanding of time. The chapters are arranged into four sections, each focused on one area of current research: Keeping Track of Time, and Temporal Representation; Memory, Awareness and the Past; Memory and Experience; Knowledge and the Past: The Epistemology and Metaphysics of Time. A general introduction gives an overview of the topics discussed and makes explicit central themes which unify the different philosophical and psychological approaches. (shrink)