This article described three heuristics that are employed in making judgements under uncertainty: representativeness, which is usually employed when people are asked to judge the probability that an object or event A belongs to class or process B; availability of instances or scenarios, which is often employed when people are asked to assess the frequency of a class or the plausibility of a particular development; and adjustment from an anchor, which is usually employed in numerical prediction when a (...) relevant value is available. These heuristics are highly economical and usually effective, but they lead to systematic and predictable errors. A better understanding of these heuristics and of the biases to which they lead could improve judgements and decisions in situations of uncertainty. (shrink)

The thirty-five chapters in this book describe various judgmental heuristics and the biases they produce, not only in laboratory experiments but in important...

Intuitive predictions and judgements under uncertainty are often mediated by judgemental heuristics that sometimes lead to biases. Our micro-developmental study suggests that a presumption of rationality is justified for adult subjects, in so far as their systematic judgemental biases appear to be due to a specific executive-inhibition failure in working memory, and not necessarily to a lack of understanding of the fundamental principles of probability. This hypothesis was tested using an experimental procedure in which 60 adult subjects were (...) trained to inhibit the classical conjunction bias on a frequency judgement task derived from Tversky and Kahneman's work. Pre- and post-test performance was assessed via a probability judgement task. The data indicated a training effect, suggesting that subjects traditionally labelled as "irrational" with respect to the classical rules of inductive reasoning are in fact "inefficient inhibitors". These findings are discussed in terms of a polymorphous view of rationality. (shrink)

The environment in which humans evolved is strongly and positively autocorrelated in space and time. Probabilistic judgments based on the assumption of independence may not yield evolutionarily adaptive behavior. A number of “faults” of human reasoning are not faulty under fuzzy arithmetic, a nonprobabilistic calculus of reasoning under uncertainty that may be closer to that underlying human decision making.

Carnap [1] aims to provide a formal explication of an informal concept (relation) he calls “confirmation”. He clarifies “E confirms H” in various ways, including: (∗) E provides some positive evidential support for H. His formal explication of “E confirms H” (in [1]) is: (1) E confirms H iff Pr(H | E) > r, where Pr is a suitable (“logical”) probability function, and r is a threshold value.

Policymakers who seek to make scientifically informed decisions are constantly confronted by scientific uncertainty and expert disagreement. This thesis asks: how can policymakers rationally respond to expert disagreement and scientific uncertainty? This is a work of non-ideal theory, which applies formal philosophical tools developed by ideal theorists to more realistic cases of policymaking under scientific uncertainty. I start with Bayesian approaches to expert testimony and the problem of expert disagreement, arguing that two popular approaches— supra-Bayesianism and (...) the standard model of expert deference—are insufficient. I develop a novel model of expert deference and show how it can deal with many of these problems raised for them. I then turn to opinion pooling, a popular method for dealing with disagreement. I show that various theoretical motivations for pooling functions are irrelevant to realistic policymaking cases. This leads to a cautious recommendation of linear pooling. However, I then show that any pooling method relies on value judgements, that are hidden in the selection of the scoring rule. My focus then narrows to a more specific case of scientific uncertainty: multiple models of the same system. I introduce a particular case study involving hurricane models developed to support insurance decision-making. I recapitulate my analysis of opinion pooling in the context of model ensembles, confirming that my hesitations apply. This motivates a shift of perspective, to viewing the problem as a decision theoretic one. I rework a recently developed ambiguity theory, called the confidence approach, to take input from model ensembles. I show how it facilitates the resolution of the policymaker’s problem in a way that avoids the issues encountered in previous chapters. This concludes my main study of the problem of expert disagreement. In the final chapter, I turn to methodological reflection. I argue that philosophers who employ the mathematical methods of the prior chapters are modelling. Employing results from the philosophy of scientific models, I develop the theory of normative modelling. I argue that it has important methodological conclusions for the practice of formal epistemology, ruling out popular moves such as searching for counterexamples. (shrink)

Cognitive Science, Volume 46, Issue 5, May 2022.

From the O.J. Simpson verdict to peace-making in the Balkans, the critical role of human judgement--complete with its failures, flaws, and successes--has never been more hotly debated and analyzed than it is today. This landmark work examines the dynamics of judgement and its impact on events that take place in human society, which require the direction and control of social policy. Research on social policy typically focuses on content. This book concentrates instead on the decision-making process itself. Drawing on 50 (...) years of empirical research in decision theory, Hammond examines the possibilities for wisdom and cognitive competence in the formation of social policies, and applies these lessons to specific examples, such as the space shuttle Challenger disaster and the health care debate. Uncertainly, he tells us, can seldom be fully eliminated; thus error is inevitable, and injustice for some unavoidable. But the capacity for make wise judgments increases to the extent that we understand the potential pitfalls and their origin. The judgment process for example involves an ongoing rivalry between intuition and analysis, accuracy and rationality. The source of this tension requires an examination of the evolutionary roots of human judgement and how these fundamental features may be changing as our civilization increasingly becomes an information and knowledge-based society. With numerous examples from law, medicine, engineering, and economics, the author dramatizes the importance of judgment and its role in the formation of social policies which affect us all, and issues the first comprehensive examination of its underlying dynamics. (shrink)

From the O.J. Simpson verdict to peace-making in the Balkans, the critical role of human judgement--complete with its failures, flaws, and successes--has never been more hotly debated and analyzed than it is today. This landmark work examines the dynamics of judgement and its impact on events that take place in human society, which require the direction and control of social policy. Research on social policy typically focuses on content. This book concentrates instead on the decision-making process itself. Drawing on 50 (...) years of empirical research in decision theory, Hammond examines the possibilities for wisdom and cognitive competence in the formation of social policies, and applies these lessons to specific examples, such as the space shuttle Challenger disaster and the health care debate. Uncertainly, he tells us, can seldom be fully eliminated; thus error is inevitable, and injustice for some unavoidable. But the capacity for make wise judgments increases to the extent that we understand the potential pitfalls and their origin. The judgment process for example involves an ongoing rivalry between intuition and analysis, accuracy and rationality. The source of this tension requires an examination of the evolutionary roots of human judgement and how these fundamental features may be changing as our civilization increasingly becomes an information and knowledge-based society. With numerous examples from law, medicine, engineering, and economics, the author dramatizes the importance of judgment and its role in the formation of social policies which affect us all, and issues the first comprehensive examination of its underlying dynamics. (shrink)

This paper interprets Knight’s views of the firm from the standpoint of his theory of human agency. Focusing on the coordination perspective, this paper argues that Knightian firms are institutions which deal with intersubjective uncertainty. The fundamental principle underlying an organized activity is the reduction of the uncertainty inherent in judgements and decisions by grouping the decisions of a particular individual and estimating the proportion of successes and failures. Coordinating activities by the use of the firm, shift focus (...) and interest from errors in human agents’ opinions of things to errors in their opinions of other people. By routinizing some judgements in the form of wage payments, firms allow the coordination of the interests of various parties and thus reduce uncertainty. Furthermore, entrepreneurs conduct economic calculation and bet their judgements on the value of the factors of production they employ. Correct entrepreneurial judgement is the ultimate source of profit. This paper calls for a research agenda on the theory of the firm to incorporate Knight’s insights.Cet article interprète la vision knightienne de la firme du point de vue de sa théorie de l’agent humain. En s’intéressant principalement à l’enjeu de la coordination, cet article soutient que les entreprises sont, selon Knight, des institutions qui “agissent” en incertitude intersubjective. Le principe fondamental qui sous-tend une activité organisée est la réduction de l’incertitude inhérent aux jugements et décisions par le regroupement des décisions d’un individu et l’estimation des proportions de succès et d’échecs. Les activités de coordination par le biais de l’entreprise, déplacent le sujet d’étude et l’intérêt des erreurs dans les opinions qu’ont les agents humains à propos des choses vers leurs erreurs d’opinion sur les autres personnes. En rendant routiniers les jugements par la pratique de paiements de salaires, les firmes permettent la coordination des intérêts de parties variées et réduisent ainsi l’incertitude. De plus, les entrepreneurs procèdent à des calculs économiques et fondent leurs jugements sur la valeur des facteurs de production qu’ils emploient. Le jugement entrepreneurial correct est l’ultime source de profit. Cet article plaide en faveur d’un programme de recherche en théorie de l’entreprise qui incorpore les perspectives ouvertes par Knight. (shrink)

In situations where we ignore everything but the space of possibilities, we ought to suspend judgment—that is, remain agnostic—about which of these possibilities is the case. This means that we cannot sum our degrees of belief in different possibilities, something that has been formalized as an axiom of non-additivity. Consistent with this way of representing our ignorance, I defend a doxastic norm that recommends that we should nevertheless follow a certain additivity of possibilities: even if we cannot sum degrees (...) of belief in different possibilities, we should be more confident in larger groups of possibilities. It is thus shown that, in the type of situation considered (in so-called ‘classical ignorance’, i.e. “behind a thin veil of ignorance”), it is epistemically rational for advocates of suspending judgment to endorse this comparative confidence; while on the other hand it is shown that, even in classical ignorance, no stronger belief—such as a precise uniform probability distribution—is warranted. (shrink)

Recent work in judgment and decisionmaking has stressed that institutions, like individuals, often rely on decisionmaking heuristics. But most of the institutional decisionmaking heuristics studied to date are highly firm- and industry-specific. This contrasts to the individual case, in which many heuristics are general-purpose rules suitable for a wide range of decision problems. Are there also general-purpose heuristics for institutional decisionmaking? In this paper, I argue that a number of methods recently developed for decisionmaking under deep uncertainty (...) have a good claim to be understood as general-purpose decisionmaking heuristics suitable for a broad range of institutional decision problems. (shrink)

Human lives are radically uncertain. Making sense of such uncertainties is the hallmark of wisdom. Sense-making requires narratives, putting them in the center stage of human everyday decision-making. Yet what if radical uncertainty is a narrative itself? Moreover, do laypeople always consider such narratives irrational? Here we pose these questions to enrich a theory of choice under uncertainty.

A diagnostic judgment of a teacher can be seen as an inference from manifest observable evidence on a student’s behavior to his or her latent traits. This can be described by a Bayesian model of in-ference: The teacher starts from a set of assumptions on the student (hypotheses), with subjective probabilities for each hypothesis (priors). Subsequently, he or she uses observed evidence (stu-dents’ responses to tasks) and knowledge on conditional probabilities of this evidence (likelihoods) to revise these assumptions. Many (...) systematic deviations from this model (biases, e.g. base-rate neglect, inverse fallacy) are reported in literature on Bayesian reasoning. In a teacher’s situation the information (hypotheses, priors, likelihoods) is usually not explicitly represented numerically (as in most research on Bayesian reasoning), but only by qualitative esti-mations in the mind of the teacher. In our study, we ask to which extent individuals (approximately) apply a rational Bayesian strategy or resort on other biased strategies of processing information for their diagnostic judgments. We explicitly pose this question with respect to non-numerical settings. To investigate this question, we developed a scenario that visually displays all relevant information (hypotheses, priors, likelihoods) in a graphically displayed hypothesis space (called “hypothegon”) – without recurring to numerical representations or mathematical procedures. 42 pre-service teach-ers were asked to judge the plausibility of different misconceptions of six students based on their responses to decimal comparison tasks (e.g. 3.39 > 3.4). Applying a Bayesian classification proce-dure, we identified three updating strategies: A Bayesian update strategy (BUS, processing all probabilities), a combined evidence strategy (CES, ignoring the prior probabilities but including all likelihoods), and a single evidence strategy (SES, only using the likelihood of the most probable hypothesis). In study 1, an instruction on the relevance of using all probabilities (priors and likelihoods) only weakly increased the processing of more information. In study 2, we found strong evidence that a visual explication of the prior-likelihood interaction led to an increase of processing the interaction of all relevant information. These results show that the phenomena found in general research on Bayesian reasoning in numerical settings extend to diagnostic judgments in non-numerical settings. (shrink)

In many situations, people are unsure in their moral judgements. In much recent philosophical literature, this kind of moral doubt has been analysed in terms of uncertainty in one’s moral beliefs. Non-cognitivists, however, argue that moral judgements express a kind of conative attitude, more akin to a desire than a belief. This paper presents a scientifically informed reconciliation of non-cognitivism and moral doubt. The central claim is that attitudinal ambivalence—the degree to which one holds conflicting attitudes towards the same (...) object—can play the role of moral doubt for non-cognitivists. I will demonstrate that ambivalence has all of the features that we would expect it to have in order to play the role of moral doubt. It is gradable, can vary through time, covaries with strength of motivation, and is suitably distinct from the other features of our moral judgements. As well as providing a defence of non-cognitivism, this insight poses a new challenge for the view: deciding how to act under moral ambivalence. (shrink)

Social judgement theory is particularly well suited to the study of medical judgements. Medical judgements characteristically involve decision making under uncertainty with inevitable error and an abundance of fallible cues. In medicine, as in other areas, SJT research has found wide variation among decision makers in their judgements and in the weighting of clinical information. Strategies inferred from case vignettes differ from physicians' self-described strategies and from the weights suggested by experts. These observations parallel recent findings of unexplained (...) variation in diagnosis and management in clinical practice that have been the source of concern in the medical community. The lens model provides one of the few methods for quantitatively analysing physicians' judgements. Contrary to what one might expect from the variation in strategies on paper cases, several studies suggest that, in practice, physicians' diagnostic judgements are highly accurate. Cognitive feedback has been less successful as a practical teaching tool than originally hoped, but some aspects of this methodology show promise, particularly in conjunction with the increasing emphasis on statistical decision support. All things considered, SJT has provided insight into physicians' decisions and gives the medical research community important tools for studying judgements in actual practice. (shrink)

People can be uncertain in their moral judgments. Philosophers have argued that such uncertainty can either refer to the underlying empirical facts (empirical uncertainty) or to the normative evaluation of these facts itself (normative uncertainty). Psychological investigations of this distinction, however, are rare. In this paper, we combined factor-analytical and experimental approaches to show that empirical and normative uncertainty describe two related but different psychological states. In Study 1, we asked N = 265 participants to describe (...) a case of moral uncertainty and to rate different aspects of their uncertainty about this case. Across this wide range of moral scenarios, our items loaded onto three reliable factors: lack of information, unclear consequences, and normative uncertainty. In Study 2, we confirmed this factor structure using predefined stimulus material. N = 402 participants each rated eight scenarios that systematically varied in their degree of uncertainty regarding the consequences of the described actions and in the value conflict that was inherent to them. The empirical uncertainty factors were mainly affected by the introduction of uncertainty regarding consequences, and the normative uncertainty factor was mainly affected by the introduction of value conflict. Our studies provide evidence that the distinction between empirical and normative uncertainty accurately describes a psychological reality. We discuss the relevance of our findings for research on moral judgments and decision-making, and folk metaethics. (shrink)

Among all their sensations, agents need to distinguish between those caused by themselves and those caused by external causes. The ability to infer agency is particularly challenging under conditions of uncertainty. Within the predictive processing framework, this should happen through active control of prediction error that closes the action-perception loop. Here we use a novel, temporally-sensitive, behavioural proxy for prediction error to show that it is minimised most quickly when volatility is high and when participants report agency, regardless (...) of the accuracy of the judgement. We demonstrate broad effects of uncertainty on accuracy of agency judgements, movement, policy selection, and hypothesis switching. Measuring autism traits, we find differences in policy selection, sensitivity to uncertainty and hypothesis switching despite no difference in overall accuracy. (shrink)

The first round about ‘The myth of ASCOT and its rival ASCO2.T: tech-noetic vs. techno-logic’ exposed the hazard in colliding obsolete disciplinary categories under outdated procedures. The orthodox jurisdiction of Ars Electronica and CERN in Collide@CERN, one of the most prominent ongoing programmes of this kind, does not eliminate the risk of missing the target by operating with categories of artists and scientists. Art is one of those disciplines with a long expired warranty, but with decay on its periphery (...) that is turning into fertile forefront territories. Fresh temporary categories are marking and spreading over these uncharted territories and sensibly interconnecting with peripheries of other disciplines. The ex-artist that is reborn in this peripheral transdisciplinary zone can be provisionally categorized as a polyphibian for its features to be carefully studied. Like amphibians, a polyphibian can coherently transcend from one medium to another, in between and beyond the disciplines. In order to research the implications of such ‘categorical’ mutations, a readymade was submitted to the organization of Collide@CERN under the licence of R. Mutt. Namely, the readymade ASCOTT (Apparatus with Super COnducting Thought Transduction) dubbed also ASCO2.T is needed as the second-order upgrade of the existing plan for ASCOT (Apparatus with Super COnducting Toroids) invented by the scientists for CERN. As is expected from the reputation of R. Mutt’s readymades – this submission was ignored and refused in just the same quiet manner as his most notorious one. But if society would not provide salons for the refused artists (Salon des Refuses) right next to the salons under the scrutiny of academically established artists, there would be no mutations and no evolution in art. Such mutations of the artist into a ‘complex and widely distributed system’ at the dispersing fringes of decomposing art was already predicted by R. Ascott. Polyphibians are the species surviving the ripening metamorphosis of disciplines by taking refuge in the unexplored transdisciplinary buffer zone. This is the only zone where a confrontation of ASCOT technology with tech-noetics of ASCO2.T is possible. The refused unknown demands not a Salon but the Interval of Suspended Judgement. In the sequel to the first round of this debate, the Interval of Suspended Judgement will be investigated. (shrink)

It is argued that causal understanding originates in experiences of acting on objects. Such experiences have consistent features that can be used as clues to causal identification and judgment. These are singular clues, meaning that they can be detected in single instances. A catalog of 14 singular clues is proposed. The clues function as heuristics for generating causal judgments under uncertainty and are a pervasive source of bias in causal judgment. More sophisticated clues such as mechanism (...) clues and repeated interventions are derived from the 14. Research on the use of empirical information and conditional probabilities to identify causes has used scenarios in which several of the clues are present, and the use of empirical association information for causal judgment depends on the presence of singular clues. It is the singular clues and their origin that are basic to causal understanding, not multiple instance clues such as empirical association, contingency, and conditional probabilities. (shrink)

In his 2018 AJP paper, Shlomo Cohen hints that deception could be a distinct subset of manipulation. We pursue this thought further, but by arguing that Cohen’s accounts of deception and manipulation are incorrect. Deception under uncertainty need not involve adding false premises to the victim’s reasoning but it must involve manipulating her response, and cases of manipulation that do not interfere with the victim’s reasoning, but rather utilize it, also exist. Therefore, deception under uncertainty must (...) be constituted by covert manipulation. (shrink)

This article reviews ECJ case law on the conceptualization and legal circumscription of the doctrine of consistent interpretation, reflecting its fundamental importance as a mode of giving effect to Community law before national authorities. Legal uncertainty, an inherent characteristic of the technique, should be reduced, it is argued, by improving the reasoning of the ECJ's judgments. In particular, a highly critical discussion of the Arcaro judgment concludes that its precedent value is very limited. A parallelism in approach to (...) both consistent interpretation and direct effect is suggested. Partly, this has already been achieved insofar as the issue of expiry of the transposition period of directives is concerned. In addition, the article suggests a reform of the case law on consistent interpretation in actions by the State versus individuals and offers explanations for the seemingly inconsistent nature of the cases producing a horizontal impact of directives despite the lack of horizontal direct effect properly so‐called (incidental effects). In considering whether the doctrine gives rise to unacceptable legal uncertainty, a comparison with the interpretive obligation under the UK Human Rights Act 1998 is made, which produces similar results. (shrink)

Explanation and prediction play an important role in medical decision making, particularly for diagnostic and treatment decisions. For the most part, explanations as well as predictions are derived from causal knowledge and have to be made under uncertainty. In cognitive psychology, these phenomena have been approached from two directions. On the one hand, there is research on knowledge representation and inferential reasoning (Holland et al. 1986; Anderson 1990). On the other hand, there is research on heuristics and biases (...) in judgments under uncertainty (Kahneman et al. 1982; Rehm & Gadenne 1990). However, no exact models have yet been developed to describe the process that leads from a given knowledge base to judgments of probabilities, i.e., from causal knowledge about the world to subjective expressions of the uncertainty associated with explanations or predictions. (shrink)

There is a controversy as to the moral status of an action in the face of uncertainty concerning a non-moral fact that is morally significant (according to an applicable moral standard): According to the objective conception, the right action is determined in light of the truth, namely the actual state of affairs (regarding the pertinent fact), whereas according to the subjective conception, the right action depends on the epistemic state of the agent, namely her (justified) belief (concerning the pertinent (...) fact). A similar debate concerns the law, with respect to uncertainty regarding a legally significant fact. In this paper, I argue that moral and legal normative concepts are ambiguous and include two aspects: The ideal aspect, which is concerned with the constitutive feature of the normative standard, and the pragmatic aspect, which determines the correct action under uncertainty . With regard to each aspect, a different conception is appropriate: The objective conception should govern the ideal aspect and the subjective conception the pragmatic aspect. And the relevant aspect (and therefore the appropriate conception) depends on the question under consideration regarding the pertinent normative standard: what is its constitutive feature or whether an action is right (according to the applicable normative standard) in the face of uncertainty. (shrink)

Belief formation and justification of belief is the subject of epistemology, philosophy of mind, and philosophy of action. In this article we are mostly interested in the application of analytic techniques for the explication of belief justification under uncertainty. We need to explicate this phenomenon in order to answer, at least in part, the question of what are the features of reasoning made in conditions that cause doubts, how people make decisions in such conditions. Arguments used for the (...) justification of such decisions have the status of plausible arguments. The crucial issues related to the analysis and evaluation of plausible arguments are of the acceptability of the premises and the transmission of their acceptability to the conclusion. In this article, we have focused on the transition from the premises to the conclusions of plausible arguments, on the transmission of justification of premises to the conclusions. To establish the peculiarities of such a transmission an outline of the semantics for such arguments is proposed. Its key component is the measures of the plausibility of the premises and rules of inference. A plausible argument itself does not provide the ultimate reason for accepting its conclusion. The justification of the conclusion also depends on other arguments that support or defeat it. So to establish the degree of justification of the conclusion we need to attribute the weights to the premises and rules of inference. We hope that this study provides at least a preliminary answer to the question of how the failure of the transmission of justification in plausible arguments differs from the failure of transmission in deductive arguments. (shrink)

Communication involves a great deal of uncertainty. Prima facie, it is therefore surprising that biological communication systems—from cellular to human—exhibit a high degree of ambiguity and often leave its resolution to contextual cues. This puzzle deepens once we consider that contextual information may diverge between individuals. In the following we lay out a model of ambiguous communication in iterated interactions between subjectively rational agents lacking a common contextual prior. We argue ambiguity’s justification to lie in endowing interlocutors with means (...) to flexibly adapt language use to each other and the context of their interaction to serve their communicative preferences. Linguistic alignment is shown to play an important role in this process; it foments convergence of contextual expectations and thereby leads to agreeing use and interpretation of ambiguous messages. We conclude that ambiguity is ecologically rational when interlocutors’ contextual expectations are generally in line or they interact multiple times in an informative context, enabling for the alignment of their expectations. In light of these results meaning multiplicity can be understood as an opportunistic outcome enabled and shaped by linguistic adaptation and contextual information. 1Meaning Multiplicity in Communication 2Ambiguous Signalling through Pragmatic Inference 2.1Preliminaries 2.2Signalling behaviour 2.3Communicative success 2.4Iterated interactions 3Predictions for Single and Iterated Interactions 3.1Simulations 3.2Exploration and past experience 3.3Preemptive adaptation 4Discussion 5Conclusion Appendix. (shrink)

Recent research has begun to investigate sensory processing in relation to nonclinical variation in traits associated with the autism spectrum disorders (ASD). We propose that existing accounts of autistic perception can be augmented by considering a role for individual differences in top-down expectations for the precision of sensory input, related to the processing of state-dependent levels of uncertainty. We therefore examined ASD-like traits in relation to the rubber-hand illusion: an experimental paradigm that typically elicits crossmodal integration of visual, tactile, (...) and proprioceptive information in an unusual illusory context. Individuals with higher ASD-like traits showed reduced effects of the rubber-hand illusion on perceived arm position and reach-to-grasp movements, compared to individuals with lower ASD-like traits. These differences occurred despite both groups reporting the typical subjective experience of the illusion concerning visuotactile integration and ownership for the rubber hand. Together these results suggest that the integration of proprioceptive information with cues for arm position derived from the illusory context differs between individuals partly in relation to traits associated with ASD. We suggest that the observed differences in sensory integration can be best explained in terms of differing expectations regarding the precision of sensory estimates in contexts that suggest uncertainty. (shrink)

We argue that contemporary psychiatry adopts a defensive strategy vis-à-vis various external sources of pressure. We will identify two of these sources – the plea for individual autonomy and the idea of Managed Care – and explain how they have promoted a strict biomedical conception of disease. The demand for objectivity, however, does not take into account the complexity of mental illness. It ignores that the psychiatrist’s profession is essentially characterized by fragility: fluctuating between scientific reduction and the irreducible complexity (...) of reality. Therefore, the psychiatrist is not in need of hard and fast rules, but of judgment. At the end, we suggest that philosophy could inject some healthy uncertainty within psychiatry in order to restore its fragile identity. Our examples are drawn from the Dutch situation but we are confident that they apply to other countries as well. (shrink)

lt is now commonplace in fallacy inquiry for many of the traditional informal fallacies to be viewed as reasonable or nonfallacious modes of argument. Central to this evaluative shift has been the attempt to examine traditional fallacies within their wider contexts of use. However, this pragmatic turn in fallacy evaluation is still in its infancy. The true potential of a contextual approach in the evaluation of the fallacies is yet to be explored. I examine how, in the context of scientific (...) inquiry, certain traditional fallacies function by conferring epistemic gains upon inquiry. Specifically, I argue that these fallacies facilitate the progression of inquiry, particularly in the initial stages ofinquiry when the epistemic context is one of uncertainty. The conception of these fallacies that emerges is that of heuristics of reasoning in contexts of epistemic uncertainty. (shrink)

This paper presents a personal view of the interaction between the analysis of choice under uncertainty and the analysis of production under uncertainty. Interest in the foundations of the theory of choice under uncertainty was stimulated by applications of expected utility theory such as the Sandmo model of production under uncertainty. This interest led to the development of generalized models including rank-dependent expected utility theory. In turn, the development of generalized expected utility (...) models raised the question of whether such models could be used in the analysis of applied problems such as those involving production under uncertainty. Finally, the revival of the state-contingent approach led to the recognition of a fundamental duality between choice problems and production problems. (shrink)

Communication involves a great deal of uncertainty. Prima facie, it is therefore surprising that biological communication systems—from cellular to human—exhibit a high degree of ambiguity and often leave its resolution to contextual cues. This puzzle deepens once we consider that contextual information may diverge between individuals. In the following we lay out a model of ambiguous communication in iterated interactions between subjectively rational agents lacking a common contextual prior. We argue ambiguity’s justification to lie in endowing interlocutors with means (...) to flexibly adapt language use to each other and the context of their interaction to serve their communicative preferences. Linguistic alignment is shown to play an important role in this process; it foments convergence of contextual expectations and thereby leads to agreeing use and interpretation of ambiguous messages. We conclude that ambiguity is ecologically rational when interlocutors’ contextual expectations are generally in line or they interact multiple times in an informative context, enabling for the alignment of their expectations. In light of these results meaning multiplicity can be understood as an opportunistic outcome enabled and shaped by linguistic adaptation and contextual information. (shrink)

Choice often proceeds in two stages: We construct a shortlist on the basis of limited and uncertain information about the options and then reduce this uncertainty by examining the shortlist in greater detail. The goal is to do well when making a final choice from the option set. I argue that we cannot realise this goal by constructing a ranking over the options at shortlisting stage which determines of each option whether it is more or less worthy of being (...) included in a shortlist. This is relevant to the 2010 UK Equality Act. The Act requires that shortlists be constructed on grounds of candidate rankings and affirmative action is only permissible for equally qualified candidates. This is misguided: Shortlisting candidates with lower expected qualifications but higher variance may raise the chance of finding an exceptionally strong candidate. If it does, then shortlisting such candidates would make eminent business sense and there is nothing unfair about it. This observation opens up room for including more underrepresented candidates with protected characteristics, as they are more likely to display greater variance in the selector’s credence functions at shortlisting stage. (shrink)

Interest in the foundations of the theory of choice under uncertainty was stimulated by applications of expected utility theory such as the Sandmo model of production under uncertainty. The development of generalized expected utility models raised the question of whether such models could be used in the analysis of applied problems such as those involving production under uncertainty. Finally, the revival of the state-contingent approach led to the recognition of a fundamental duality between choice (...) problems and production problems. (shrink)

We discuss several features of coherent choice functions—where the admissible options in a decision problem are exactly those that maximize expected utility for some probability/utility pair in fixed set S of probability/utility pairs. In this paper we consider, primarily, normal form decision problems under uncertainty—where only the probability component of S is indeterminate and utility for two privileged outcomes is determinate. Coherent choice distinguishes between each pair of sets of probabilities regardless the “shape” or “connectedness” of the sets (...) of probabilities. We axiomatize the theory of choice functions and show these axioms are necessary for coherence. The axioms are sufficient for coherence using a set of probability/almost-state-independent utility pairs. We give sufficient conditions when a choice function satisfying our axioms is represented by a set of probability/state-independent utility pairs with a common utility. (shrink)

Three challenges to a unified understanding of delusions emerge from Radden's On Delusion (2011). Here, I propose that in order to respond to these challenges, and to work towards a unifying framework for delusions, we should see delusions as arising in inference under uncertainty. This proposal is based on the observation that delusions in key respects are surprisingly like perceptual illusions, and it is developed further by focusing particularly on individual differences in uncertainty expectations.

This paper describes a cubic water tank equipped with a movable partition receiving various amounts of liquid used to represent joint probability distributions. This device is applied to the investigation of deductive inferences under uncertainty. The analogy is exploited to determine by qualitative reasoning the limits in probability of the conclusion of twenty basic deductive arguments (such as Modus Ponens, And-introduction, Contraposition, etc.) often used as benchmark problems by the various theoretical approaches to reasoning under uncertainty. (...) The probability bounds imposed by the premises on the conclusion are derived on the basis of a few trivial principles such as "a part of the tank cannot contain more liquid than its capacity allows", or "if a part is empty, the other part contains all the liquid". This stems from the equivalence between the physical constraints imposed by the capacity of the tank and its subdivisions on the volumes of liquid, and the axioms and rules of probability. The device materializes de Finetti's coherence approach to probability. It also suggests a physical counterpart of Dutch book arguments to assess individuals' rationality in probability judgments in the sense that individuals whose degrees of belief in a conclusion are out of the bounds of coherence intervals would commit themselves to executing physically impossible tasks. (shrink)

Underscoring the economic significance of the Knightian distinction between risk and uncertainty, Don Katzner forcefully challenges the continued dominance of the expected utility model based on subjective probability in macroeconomic analysis and offers in its place a simple yet elegant model of decision making inspired by the pioneering work of G.L.S. Shackle. In doing so, Katzner lends support to a research program to identify a more coherent and empirically grounded theory of decision making under uncertainty. Our paper (...) makes three contributions to this program. First, we argue that the appropriate choice of a model of individual behavior under uncertainty cannot be adjudicated merely on logical, a priori grounds, but must ultimately be based on consistency with observed behavior. There are many internally consistent models and their external conditions of validity hardly ever rely on inconceivable scenarios. Second, while Katzner’s model certainly provides a plausible foundation for understanding choice under uncertainty, we suggest that it is somewhat underdetermined. It requires further theoretical articulation to yield testable predictions which differentiate it from competing approaches. Third, we discuss recent experimental findings that may need to be addressed by any satisfactory theoretical account of decision making under uncertainty. (shrink)

Conviction Narrative Theory (CNT) is conceptually so multifaceted as to make critical evaluation difficult. It also omits one course of action: Active engagement with the world. Parsing the developmental and mechanistic processes within CNT would allow for a rigorous research programme to put the account under test. I propose a unifying account based on active inference.

Reasoning under uncertainty, that is, making judgements with only partial knowledge, is a major theme in artificial intelligence. Professor Paris provides here an introduction to the mathematical foundations of the subject. It is suited for readers with some knowledge of undergraduate mathematics but is otherwise self-contained, collecting together the key results on the subject, and formalising within a unified framework the main contemporary approaches and assumptions. The author has concentrated on giving clear mathematical formulations, analyses, justifications and consequences (...) of the main theories about uncertain reasoning, so the book can serve as a textbook for beginners or as a starting point for further basic research into the subject. It will be welcomed by graduate students and research workers in logic, philosophy, and computer science as a textbook for beginners, a starting point for further basic research into the subject, and not least, an account of how mathematics and artificial intelligence can complement and enrich each other. (shrink)

Professor Dreze is a highly respected mathematical economist and econometrician. This book brings together some of his major contributions to the economic theory of decision making under uncertainty, and also several essays. These include an important essay on 'Decision theory under moral hazard and state dependent preferences' that significantly extends modern theory, and which provides rigorous foundations for subsequent chapters. Topics covered within the theory include decision theory, market allocation and prices, consumer decisions, theory of the firm, (...) labour contracts, and public decisions. (shrink)

The paper addresses the question, how policy decisions under uncertainty depend on the underlying welfare concept. We study three different welfare measures: The first is directly based on the ex ante (expected) utility of a representative consumer whereas the second relies on an ex ante and the third on an ex post valuation of policy changes compared to the status quo. We show that decisions based on these measures coincide if and only if risk-neutral expected utility maximization is (...) applied. Differences between the decisions are analyzed for both, risk-averse expected utility maximization and the MaxiMin criterion. For risk-averse decision makers, differences between the first and the second concept arise if the absolute risk-aversion of the decision maker is not constant in income. For risk-aversion and the MaxiMin criterion, the effort levels to provide a public good based on an optimization of ex post utility changes exceed those based on the first or second concept. Implications for environmental policy decisions based on the concepts of abatement costs and benefits from abatement are discussed. (shrink)