The Sure-Thing Principle famously appears in Savage’s axiomatization of Subjective Expected Utility. Yet Savage introduces it only as an informal, overarching dominance condition motivating his separability postulate P2 and his state-independence postulate P3. Once these axioms are introduced, by and large, he does not discuss the principle any more. In this note, we pick up the analysis of the Sure-Thing Principle where Savage left it. In particular, we show that each of P2 and P3 is equivalent to a dominance condition; (...) that they strengthen in different directions a common, basic dominance axiom; and that they can be explicitly combined in a unified dominance condition that is a candidate formal statement for the Sure-Thing Principle. Based on elementary proofs, our results shed light on some of the most fundamental properties of rational choice under uncertainty. In particular they imply, as corollaries, potential simplifications for Savage’s and the Anscombe- Aumann axiomatizations of Subjective Expected Utility. Most surprisingly perhaps, they reveal that in Savage’s axiomatization, P3 can be weakened to a natural strengthening of so-called Obvious Dominance. (shrink)

I examine the once popular claim according to which interpersonal comparisons of welfare are necessary for social choice. I side with current social choice theorists in emphasizing that, on a narrow construal, this necessity claim is refuted beyond appeal. However, I depart from the opinion presently prevailing in social choice theory in highlighting that on a broader construal, this claim proves not only compatible with, but even comforted by, the current state of the field. I submit that all in all, (...) the most accurate philosophical assessment consists not in flatly rejecting this necessity claim, but in accepting it in a suitably revised form. (shrink)

The representational theory of measurement has long been the central paradigm in the philosophy of measurement. Such is not the case anymore, partly under the influence of the critique according to which RTM offers too poor descriptions of the measurement procedures actually followed in science. This can be called the metrological critique of RTM. I claim that the critique is partly irrelevant. This is because, in general, RTM is not in the business of describing measurement procedures, be it in idealized (...) form. To support this claim, I present various cases where RTM can be said to investigate measurement without providing any measurement procedure. Such limit cases lead to a better understanding of the RTM project. They also illustrate some of the questions which the philosophy of measurement can explore, when it is ready to go beyond the metrological viewpoint. (shrink)

Supra-Bayesianism is the Bayesian response to learning the opinions of others. Probability pooling constitutes an alternative response. One natural question is whether there are cases where probability pooling gives the supra-Bayesian result. This has been called the problem of Bayes-compatibility for pooling functions. It is known that in a common prior setting, under standard assumptions, linear pooling cannot be nontrivially Bayes-compatible. We show by contrast that geometric pooling can be nontrivially Bayes-compatible. Indeed, we show that, under certain assumptions, geometric and (...) Bayes-compatible pooling are equivalent. Granting supra-Bayesianism its usual normative status, one upshot of our study is thus that, in a certain class of epistemic contexts, geometric pooling enjoys a normative advantage over linear pooling as a social learning mechanism. We discuss the philosophical ramifications of this advantage, which we show to be robust to variations in our statement of the Bayes-compatibility problem. (shrink)

This paper examines the preference-based approach to the identification of beliefs. It focuses on the main problem to which this approach is exposed, namely that of state-dependent utility. First, the problem is illustrated in full detail. Four types of state-dependent utility issues are distinguished. Second, a comprehensive strategy for identifying beliefs under state-dependent utility is presented and discussed. For the problem to be solved following this strategy, however, preferences need to extend beyond choices. We claim that this a necessary feature (...) of any complete solution to the problem of state-dependent utility. We also argue that this is the main conceptual lesson to draw from it. We show that this lesson is of interest to both economists and philosophers. (shrink)

It is widely held that under ordinal utility, utility differences are ill-defined. Allegedly, for these to be well-defined (without turning to choice under risk or the like), one should adopt as a new kind of primitive quaternary relations, instead of the traditional binary relations underlying ordinal utility functions. Correlatively, it is also widely held that the key structural properties of quaternary relations are entirely arbitrary from an ordinal point of view. These properties would be, in a nutshell, the hallmark of (...) cardinal utility. While much is obviously true in these two tenets, this note explains why, as stated, they should be abandoned. Any ordinal utility function induces a rich quaternary relation. There is such a thing as ordinal utility differences. Furthermore, this induced quaternary relation respects, apart from completeness, the most standard structural properties of quaternary relations. These properties are, from an ordinal point of view, anything but arbitrary; from a quaternary perspective only completeness should be considered the hallmark—if any—of cardinal utility. These facts are explained to be especially relevant to the critical appreciation of the ordinalist methodology. (shrink)

We reexamine some of the classic problems connected with the use of cardinal utility functions in decision theory, and discuss Patrick Suppes's contributions to this field in light of a reinterpretation we propose for these problems. We analytically decompose the doctrine of ordinalism, which only accepts ordinal utility functions, and distinguish between several doctrines of cardinalism, depending on what components of ordinalism they specifically reject. We identify Suppes's doctrine with the major deviation from ordinalism that conceives of utility functions as (...) representing preference differences, while being non- etheless empirically related to choices. We highlight the originality, promises and limits of this choice-based cardinalism. (shrink)

In this paper, I examine the decision-theoretic status of risk attitudes. I start by providing evidence showing that the risk attitude concepts do not play a major role in the axiomatic analysis of the classic models of decision-making under risk. This can be interpreted as reflecting the neutrality of these models between the possible risk attitudes. My central claim, however, is that such neutrality needs to be qualified and the axiomatic relevance of risk attitudes needs to be re-evaluated accordingly. Specifically, (...) I highlight the importance of the conditional variation and the strengthening of risk attitudes, and I explain why they establish the axiomatic significance of the risk attitude concepts. I also present several questions for future research regarding the strengthening of risk attitudes. (shrink)

This note considers the conceptual part of Sen’s «Internal Consistency of Choice». Amongst the various claims this paper features, two are singled out. A first, negative, claim is that no formal condition of choice consistency is normatively compelling without exception. A second, positive, claim, is that a formal condition of choice consistency is normatively compelling only under some assumptions involving preference. Here, the puzzling choices Sen puts forward are scrutinized and it is argued that such a scrutiny leads to question (...) the negative claim, but in a subtle way, so that the positive claim is comforted, even strengthened. -/- Cette note examine la partie conceptuelle d’un article de Sen, «Internal Consistency of Choice». Elle isole deux thèses parmi celles que Sen défend. Une première, négative, est qu’aucune condition formelle de cohérence du choix n’est normativement valable sans exception. Une seconde, positive, est qu’une condition formelle de cohérence du choix n’est normativement valable que sous des suppositions faisant intervenir la préférence. Nous procédons à une analyse détaillée des choix énigmatiques dont Sen prend argument et affirmons que cet examen mène à remettre en cause la thèse négative, mais d’une manière subtile qui confirme — même renforce — la thèse positive. (shrink)

State-dependent utility is a problem for the behavioural branch of decision theory under uncertainty. It questions the very possibility that beliefs be revealed by choice data. According to the current literature, all models of beliefs are equally exposed to the problem. Moreover, the problem is solvable only when the decision-maker can influence the resolution of uncertainty. This article gives grounds to reject these two views. The various models of beliefs can be shown to be unequally exposed to the problem of (...) state-dependent utility. The problem can be argued to be solved even when the decision-maker has no influence over the resolution of uncertainty. The implications of such reappraisal for a philosophical appreciation of the revealed preference methodology are discussed. (shrink)

The basic axioms or formal conditions of decision theory, especially the ordering condition put on preferences and the axioms underlying the expected utility formula, are subject to a number of counter-examples, some of which can be endowed with normative value and thus fall within the ambit of a philosophical reflection on practical rationality. Against such counter-examples, a defensive strategy has been developed which consists in redescribing the outcomes of the available options in such a way that the threatened axioms or (...) conditions continue to hold. We examine how this strategy performs in three major cases: Sen's counterexamples to the binariness property of preferences, the Allais paradox of EU theory under risk, and the Ellsberg paradox of EU theory under uncertainty. We find that the strategy typically proves to be lacking in several major respects, suffering from logical triviality, incompleteness, and theoretical insularity. To give the strategy more structure, philosophers have developed “principles of individuation”; but we observe that these do not address the aforementioned defects. Instead, we propose the method of checking whether the strategy can overcome its typical defects once it is given a proper theoretical expansion. We find that the strategy passes the test imperfectly in Sen's case and not at all in Allais's. In Ellsberg's case, however, it comes close to meeting our requirement. But even the analysis of this more promising application suggests that the strategy ought to address the decision problem as a whole, rather than just the outcomes, and that it should extend its revision process to the very statements it is meant to protect. Thus, by and large, the same cautionary tale against redescription practices runs through the analysis of all three cases. A more general lesson, simply put, is that there is no easy way out from the paradoxes of decision theory. (shrink)

We examine whether a taxpayer’s decision to choose a taxpayer-favorable characterization of income is associated with contextual and individual dimensions of that decision. Using a 2 × 2 factorial experimental design, we manipulate the prevailing social norm on whether there is a general belief that a specific form of income should be characterized as a capital gain or as ordinary income, and the group affiliation on whether the individual is making a tax characterization decision as a sole proprietor or as (...) a member of a group practice. Moreover, we measure participants’ fairness perception of characterizing the income as capital gains versus ordinary. We study the decisions of 180 graduate business and accounting students from two US business schools to explore these dimensions using a tax-ambiguous income situation. Results indicate that both contextual and individual dimensions impact taxpayer decisions. Specifically, the social norm and fairness perception of characterizing income as capital gains affects the likelihood of choosing such a characterization. Being a sole proprietor or a member of a group practice does not have any significant main effect. However, relative to all other conditions, taxpayers are most likely to characterize income as capital gains when both the social norms are for capital gains characterization and when the taxpayer is a member of a group practice. Results remain largely robust to a variety of alternative explanations. We conclude the paper with a discussion of our findings and their implications for tax policy, enforcement, and research. (shrink)

Regulatory schema has shifted from government to governance-based systems. One particular form that has emerged at the international level is the multi-stakeholder voluntary code of conduct (MSVC). We argue that such codes are not only simply mechanisms by which various stakeholders attempt to govern the action of the corporation but also systems by which each stakeholder attempts to gain or retain some legitimacy goal. Each stakeholder is motivated by strategic legitimacy goal to join the code, and once a member, is (...) also required to assist in maintaining the institutional legitimacy of the code, resulting in “networked legitimacy.” We begin our analysis of these systems by first exploring the growth and structure of such MSVCs, and then building an analytical framework using strategic and institutional legitimacy as they apply to such MSVCs. We contribute to the codes of conduct literature by developing the construct of networked legitimacy from strategic and institutional legitimacy. We then apply our framework to the United Nations Global Compact, one of the predominant MSVCs today. In doing so, we: (1) demonstrate how different stakeholders are pursuing different types of legitimacy through their participation in the code, (2) examine the specific opportunities and risks in terms of what we have called “networked legitimacy” posed by the institutional design of actual MSVCs, and (3) create an argument for three pillars supporting the legitimacy of MSVCs. (shrink)

This paper offers a critical analysis of two central issues in Luigi Ferrajoli’s Principia iuris , and more generally of his theory of rights. One is the way in which ‘expectations’ play a crucial role in his deontic theory by establishing the logical basis for his guarantee-based conception of law and rights. The axiomatic way in which Ferrajoli arrives at his conception of fundamental rights is questioned, for it fails to give a full account of the nature of subjective rights. (...) The other issues discussed here is Ferrajoli’s own defence of the universality of fundamental rights, and how this is made to depend on a ‘normative technique’ that one can associate with legal discourse and modern law in Western societies. This, however, poses the problem of how this formal universalism can be reconciled with the intercultural dialogue that Ferrajoli also advocates. (shrink)

Despite several criticisms surrounding the DSM classification in psychiatry, a significant bulk of research on mental conditions still operates according to two core assumptions: a) homogeneity, that is the idea that mental conditions are sufficiently homogeneous to justify generalization; b) additive comorbidity, that is the idea that the coexistence of multiple conditions in the same individual can be interpreted as additive. In this paper we take autism research as a case study to show that, despite a plethora of criticism, psychiatric (...) research often continues to operate in accordance with this model. Then we argue that such a model runs into problems once facts about comorbidity are taken into account. Finally, we offer some suggestions on how to tackle the challenge raised by comorbidity and its impact on heterogeneity. To do so, we explore transdiagnostic stratification accounts and network models to show that combining these approaches can move us in the right direction. (shrink)

Ontologies represent the standard way to model the knowledge about specific domains. This holds also for the legal domain where several ontologies have been put forward to model specific kinds of legal knowledge. Both for standard users and for law scholars, it is often difficult to have an overall view on the existing alternatives, their main features and their interlinking with the other ontologies. To answer this need, in this paper, we address an analysis of the state-of-the-art in legal ontologies (...) and we characterise them along with some distinctive features. This paper aims to guide generic users and law experts in selecting the legal ontology that better fits their needs and in understanding its specificity so that proper extensions to the selected model could be investigated. (shrink)

Ontologies represent the standard way to model the knowledge about specific domains. This holds also for the legal domain where several ontologies have been put forward to model specific kinds of legal knowledge. Both for standard users and for law scholars, it is often difficult to have an overall view on the existing alternatives, their main features and their interlinking with the other ontologies. To answer this need, in this paper, we address an analysis of the state-of-the-art in legal ontologies (...) and we characterise them along with some distinctive features. This paper aims to guide generic users and law experts in selecting the legal ontology that better fits their needs and in understanding its specificity so that proper extensions to the selected model could be investigated. (shrink)

Ontologies represent the standard way to model the knowledge about specific domains. This holds also for the legal domain where several ontologies have been put forward to model specific kinds of legal knowledge. Both for standard users and for law scholars, it is often difficult to have an overall view on the existing alternatives, their main features and their interlinking with the other ontologies. To answer this need, in this paper, we address an analysis of the state-of-the-art in legal ontologies (...) and we characterise them along with some distinctive features. This paper aims to guide generic users and law experts in selecting the legal ontology that better fits their needs and in understanding its specificity so that proper extensions to the selected model could be investigated. (shrink)

En este artículo se resaltan las semejanzas entre el teatro griego de los siglos V y IV A.C, y los aspectos dramáticos de la Apología de Sócrates y el Banquete de Platón, argumentando a favor del carácter filosófico de aspectos como la puesta en escena y el manejo de los personajes. Parahacerlo se replantea la relación entre la obra de Platón y la de los poetas, cambiando el foco de atención de su famosa censura a las representaciones teatrales, para iluminar (...) su empleo de mecanismos dramatúrgicos articulados con planteamientos éticos y políticos. Se concluye que Platón utiliza recursos del teatro griego, pero los extrapola y los transforma creando un nuevo tipo de drama. (shrink)

The paper addresses the problem of imaginative resistance in science, that is, why and under what circumstances imagination sometimes resists certain scenarios. In the first part, the paper presents and discusses two accounts concerning the problem and relevant for the main thesis of this study. The first position is that of Gendler (Journal of Philosophy 97:55–81, 2000), (Gendler, in: Nichols (ed) The Architecture of the Imagination: New essays on pretence, possibility and fiction, Oxford University Press, New York, 2006a), (Gendler & (...) Liao, in: Gibson, Carroll (eds) The routledge companion to philosophy of literature, Routledge, New York, 2016), according to which imaginative resistance mainly concerns evaluative scenarios, presenting deviant moral attitudes. The second account examined is that of Kim et al. (in: Cova, Réhault (eds) Advances in experimental philosophy of aesthetics, Bloomsbury, London, 2018), who insisted on the link between imaginative resistance on the one hand and counterfactual and counterdescriptive scenarios on the other. In the light of both theories, this paper discusses the importance of addressing the problem of imaginative resistance in the scientific enterprise in the light of some mechanisms of embodied simulation, based on the activity of mirror neurons and investigated within the framework of the Embodied Simulation Theory. (shrink)

A substantial body of experimental evidence has demonstrated that labels have an impact on infant categorization processes. Yet little is known regarding the nature of the mechanisms by which this effect is achieved. We distinguish between two competing accounts: supervised name‐based categorization and unsupervised feature‐based categorization. We describe a neurocomputational model of infant visual categorization, based on self‐organizing maps, that implements the unsupervised feature‐based approach. The model successfully reproduces experiments demonstrating the impact of labeling on infant visual categorization reported in (...) Plunkett, Hu, and Cohen (2008). It mimics infant behavior in both the familiarization and testing phases of the procedure, using a training regime that involves only single presentations of each stimulus and using just 24 participant networks per experiment. The model predicts that the observed behavior in infants is due to a transient form of learning that might lead to the emergence of hierarchically organized categorical structure and that the impact of labels on categorization is influenced by the perceived similarity and the sequence in which the objects are presented. The results suggest that early in development, say before 12 months old, labels need not act as invitations to form categories nor highlight the commonalities between objects, but they may play a more mundane but nevertheless powerful role as additional features that are processed in the same fashion as other features that characterize objects and object categories. (shrink)

A model is computable if its domain is a computable set and its relations and functions are uniformly computable. Let be a computable model and let R be an extra relation on the domain of . That is, R is not named in the language of . We define to be the set of Turing degrees of the images f under all isomorphisms f from to computable models. We investigate conditions on and R which are sufficient and necessary for to (...) contain every Turing degree. These conditions imply that if every Turing degree 0″ can be realized in via an isomorphism of the same Turing degree as its image of R, then contains every Turing degree. We also discuss an example of and R whose coincides with the Turing degrees which are 0′. (shrink)

We construct a recursive model , a recursive subset R of its domain, and a Turing degree x 0 satisfying the following condition. The nonrecursive images of R under all isomorphisms from to other recursive models are of Turing degree x and cannot be recursively enumerable.

Despite several criticisms surrounding the DSM classification in psychiatry, a significant bulk of research on mental conditions still operates according to two core assumptions: a) homogeneity, that is the idea that mental conditions are sufficiently homogeneous to justify generalization; b) additive comorbidity, that is the idea that the coexistence of multiple conditions in the same individual can be interpreted as additive. In this paper we take autism research as a case study to show that, despite a plethora of criticism, psychiatric (...) research often continues to operate in accordance with this model. Then we argue that such a model runs into problems once facts about comorbidity are taken into account. Finally, we offer some suggestions on how to tackle the challenge raised by comorbidity and its impact on heterogeneity. To do so, we explore transdiagnostic stratification accounts and network models to show that combining these approaches can move us in the right direction. (shrink)

In this paper, I investigate the betting behavior of a decision-maker who can influence the likelihood of the events upon which she is betting. In decision theory, this is best known as a situation of moral hazard. Focusing on a particularly simple case, I sketch the first systematic analysis of moral hazard in the canonical Savage framework. From the results of this analysis, I draw two philosophical conclusions. First, from an observational and a descriptive point of view, there need to (...) be no incompatibility between moral hazard and the Savage framework. This qualifies the incompatibility view, that is ubiquitous in decision theory. Second, in general, moral hazard is not sufficient to overcome the challenges posed by state-dependent utility to the behavioral identification of beliefs. This qualifies the sufficiency view, that is influential in decision theory. These two philosophical conclusions are the main contributions of my paper. (shrink)

The outbreak of SARS-CoV-2 has exposed a shared condition of vulnerability on a global scale. How can we use vulnerability as an effective paradigm in order to foster collective political initiatives? This essay claims that the idea of care is key to understand the vulnerability framework as being both an epistemic and a political resource to address ethical issues. The first half of the essay recollects several arguments in Adriana Cavarero’s and Judith Butler’s most recent works, insofar as both theorists (...) have insisted on the notion of vulnerability in order to interpret contemporary political mobilizations. The second part of the essay retraces a constellation of practices of care in the works of several Black and decolonial feminist thinkers situated in different socio-political contexts. Whereas for Christina Sharpe and Saidiya Hartman the focus is on the matter of Blackness and Black lives in their constitutive vulnerability, both Cristina Rivera Garza’s and Sayak Valencia’s works remarkably insist on the specific socio-political context of today’s Mexico. These authors urge the readers to adopt a critical posture when encountering official narratives, also because in their texts they exhibit their own vulnerability. For them, writing, their writing is an ethical demand to imagine alternatives and to foster new entanglements between bodies persisting on the margins, at the limits of the norms that regulate legibility. (shrink)

The title of the following essay echoes one of Bobbio’s most famous books, and emphasizes one of its main issues: that of providing a “foundation” for the idea of rights. This essay summarizes what Bobbio means by “the age of rights” and presents his principal criticisms of any supposedly “absolute foundation” for rights. In exploring the notion of an age of rights without foundations Bobbio raised a number of crucial issues that effectively anticipated the contemporary debate around problems concerning the (...) historical transformation of rights and the origin of these rights in specific social processes, the deontological status of rights and the connection between rights and duties, the contrast between universalism and relativism, the relationship between different “generations of rights” and social rights, and the international protection of rights in relation to the idea of “institutional pacificism.” To pursue further reflection and enquiry along these lines would be a way of remaining faithful to the spirit of Bobbio’s teaching. But in order to do so it would also be necessary to question some of the methodological assumptions of Bobbio’s work: normativism in the area of jurisprudence, neopositivism in the field of epistemology, and the analytical approach in the history of ideas. (shrink)

The contemporary State power is concentrated in the hands of the legislative, executive and judicial powers, which is traditionally referred to as the principle of the division of State power. The separation of State power and the attribution of the function of the interpretation and application of statutory law to courts were like “letting the genie out of the bottle”. Having started with a mechanical application of the statutory law, the courts, armed with various doctrines on interpretation of law, have (...) in the meantime started creating rules themselves and turned into rivals to the legislator. In addition to having started making the law, the courts have also begun exerting control over both the legislative (constitutional justice) and the executive (administrative justice) powers. The acknowledgement of the fact that by interpreting and applying the law, the court is simultaneously making it, gives rise to a host of questions, e.g.: if the court is the guardian of law, who is the guardian of the court? How to separate the interpretation of law from its creation? If the court acts as a lawmaker, then maybe in future, the court will turn into a sole lawmaker?, etc. (shrink)

Some philosophers claim that perception immediately and prima facie justifies belief in virtue of its phenomenal character (Huemer, Skepticism and the veil of perception. Rowman & Littlefield, Lanham, 2001; Pryor, There is immediate justification. In: Steup M, Sosa E (eds) Contemporary debates in epistemology. Blackwell, London (2014), pp. 181–202, 2005). To explain this special justificatory power, some appeal to perception’s presentational character: the idea that perceptual experience presents its objects as existing here-and-now (Chudnoff, Intuition. Oxford University Press, Oxford, 2013; Berghofer, (...) Husserl Stud 34(2):145–170, 2018). As some philosophers have noted, if perception justifies in virtue of its presentational character alone, the kind of content perception has should not matter for perceptual justification; more precisely, it should not matter whether perceptual content is propositional or not (e.g., Smithies, The epistemic role of consciousness. Oxford University Press, Oxford, 2019; Kriegel, Australas J Philos, 2021). However, most philosophers tend to resist this conclusion, holding that perception must be propositional in order to justify, on the ground that all our model of justification are propositional (e.g., Gauker, Philos Perspect 26(1):19–50, 2012). This paper challenges this claim. The paper consists of a negative and a positive part. In the negative part, I discuss and reject the master argument for the propositionality of perception; the conclusion is that propositional content is neither sufficient nor necessary to explain perception’s justificatory power. In the positive part, I take this conclusion seriously and outline an objectual model of perceptual justification. I define objectual attitudes as mental states whose content is not a full proposition, but a sub-propositional representational item, such as the representation of objects, properties, and kinds (Grzankowski and Montague, Non-propositional intentionality. Oxford University Press, Oxford, 2018), and show that it is plausible that some perceptions and some beliefs are attitudes of this kind. I then argue that objectual perceptual experiences have the right kind of phenomenal character and the right kind of structure to serve for immediate prima facie justification. I conclude by defending my objectual model from three objections. (shrink)

Several theories propose that one of the core functions of inner speech (IS) is to support subjects in the completion of cognitively effortful tasks, especially those involving executive functions (EF). In this paper we focus on two populations who notoriously encounter difficulties in performing EF tasks, namely, people diagnosed with schizophrenia who experience auditory verbal hallucinations (Sz-AVH) and people within the Autism Spectrum Conditions (ASC). We focus on these two populations because they represent two different ways in which IS can (...) fail to help in EF tasks, which can be illustrative for other mental conditions. First, we review the main components of EF (Section 1). Then we explain the functions that IS is taken to perform in the domain of EF (Section 2) and review the evidence concerning problems about EF in the two populations of our study: Sz-AVH (Section 3) and ASC (Section 4). After this we further detail our account about what a properly functioning IS can do for both populations and how different IS profiles may impact EF performance: in the case of Sz-AVH, the uncontrolled and intrusive character of IS negatively affects EF performance, whereas in ASC, EF is not sufficiently supported by IS, given the tendency in this population to present a diminished use of IS (Section 5). We finally briefly discuss Attention Deficit/Hyperactivity Disorder (ADHD) and Developmental Language Disorders (DLD). (shrink)

We investigate risk attitudes when the underlying domain of payoffs is finite and the payoffs are, in general, not numerical. In such cases, the traditional notions of absolute risk attitudes, that are designed for convex domains of numerical payoffs, are not applicable. We introduce comparative notions of weak and strong risk attitudes that remain applicable. We examine how they are characterized within the rank-dependent utility model, thus including expected utility as a special case. In particular, we characterize strong comparative risk (...) aversion under rank-dependent utility. This is our main result. From this and other findings, we draw two novel conclusions. First, under expected utility, weak and strong comparative risk aversion are characterized by the same condition over finite domains. By contrast, such is not the case under non-expected utility. Second, under expected utility, weak comparative risk aversion is characterized by the same condition when the utility functions have finite range and when they have convex range. By contrast, such is not the case under non-expected utility. Thus, considering comparative risk aversion over finite domains leads to a better understanding of the divide between expected and non-expected utility, more generally, the structural properties of the main models of decision-making under risk. (shrink)

Consider a subjective expected utility preference relation. It is usually held that the representations which this relation admits differ only in one respect, namely, the possible scales for the measurement of utility. In this paper, I discuss the fact that there are, metaphorically speaking, two additional dimensions along which infinitely many more admissible representations can be found. The first additional dimension is that of state-dependence. The second—and, in this context, much lesser-known—additional dimension is that of act-dependence. The simplest implication of (...) their usually neglected existence is that the standard axiomatizations of subjective expected utility fail to provide the measurement of subjective probability with satisfactory behavioral foundations. (shrink)

An obituary of Philippe Mongin (1950-2020).

Cette note épistémologique porte sur le statut, en théorie de la décision, des concepts d’attitude par rapport au risque. A première vue, l’analyse axiomatique ne les exploite pas, ce qui reflète une certaine neutralité des modèles de décision au sujet de l’attitude par rapport au risque. Mais un examen plus poussé met en valeur la variation conditionnelle et le renforcement de l’attitude par rapport au risque, qui rattachent les concepts d’attitude par rapport au risque à l’analyse axiomatique.

We consider embeddings of structures which preserve spectra: if g: M → S with S computable, then M should have the same Turing degree spectrum (as a structure) that g(M) has (as a relation on S). We show that the computable dense linear order L is universal for all countable linear orders under this notion of embedding, and we establish a similar result for the computable random graph G. Such structures are said to be spectrally universal. We use our results (...) to answer a question of Goncharov, and also to characterize the possible spectra of structures as precisely the spectra of unary relations on G. Finally, we consider the extent to which all spectra of unary relations on the structure L may be realized by such embeddings, offering partial results and building the first known example of a structure whose spectrum contains precisely those degrees c with c′ ≥T 0″. (shrink)

Let be an infinite computable structure, and let R be an additional computable relation on its domain A. The syntactic notion of formal hypersimplicity of R on , first introduced and studied by Hird, is analogous to the computability-theoretic notion of hypersimplicity of R on A, given the definability of certain effective sequences of relations on A. Assuming that R is formally hypersimple on , we give general sufficient conditions for the existence of a computable isomorphic copy of on whose (...) domain the image of R is hypersimple and of arbitrary nonzero computably enumerable Turing degree. (shrink)