Preferences in Decision Theory

Savage's framework of subjective preference among acts provides a paradigmatic derivation of rational subjective probabilities within a more general theory of rational decisions. The system is based on a set of possible states of the world, and on acts, which are functions that assign to each state a consequence€. The representation theorem states that the given preference between acts is determined by their expected utilities, based on uniquely determined probabilities (assigned to sets of states), and numeric utilities assigned to consequences. (...) Savage's derivation, however, is based on a highly problematic well-known assumption not included among his postulates: for any consequence of an act in some state, there is a "constant act" which has that consequence in all states. This ability to transfer consequences from state to state is, in many cases, miraculous -- including simple scenarios suggested by Savage as natural cases for applying his theory. We propose a simplification of the system, which yields the representation theorem without the constant act assumption. We need only postulates P1-P6. This is done at the cost of reducing the set of acts included in the setup. The reduction excludes certain theoretical infinitary scenarios, but includes the scenarios that should be handled by a system that models human decisions. (shrink)

Among the possible solutions to the paradoxes of collective preferences, single-peakedness is significant because it has been associated to a suggestive conceptual interpretation: a single-peaked preference profile entails that, although individuals may disagree on which option is the best, they conceptualize the choice along a shared unique dimension, i.e. they agree on the rationale of the collective decision. In this article, we discuss the relationship between the structural property of singlepeakedness and its suggested interpretation as uni-dimensionality of a social choice. (...) In particular, we offer a formalization of the relationship between single-peakedness and its conceptual counterpart, we discuss their logical relations, and we question whether single-peakedness provides a rationale for collective choices. (shrink)

Public deliberation has been defended as a rational and noncoercive way to overcome paradoxical results from democratic voting, by promoting consensus on the available alternatives on the political agenda. Some critics have argued that full consensus is too demanding and inimical to pluralism and have pointed out that single-peakedness, a much less stringent condition, is sufficient to overcome voting paradoxes. According to these accounts, deliberation can induce single-peakedness through the creation of a ‘meta-agreement’, that is, agreement on the dimension according (...) to which the issues at stake are ‘conceptualized’. We argue here that once all the conditions needed for deliberation to bring about single-peakedness through meta-agreement are unpacked and made explicit, meta-agreement turns out to be a highly demanding condition, and one that is very inhospitable to pluralism. (shrink)

The best justification of time-discounting is roughly that it is rational to care less about your more distant future because there is less of you around to have it. I argue that the standard version of this argument, which treats both psychological continuity and psychological connectedness as reasons to care about your future, can only rationalize an irrational—because exploitable—form of future discounting.

Taking the philosophical standpoint, this article compares the mathematical theory of individual decision-making with the folk psychology conception of action, desire and belief. It narrows down its topic by carrying the comparison vis-à-vis Savage's system and its technical concept of subjective probability, which is referred to the basic model of betting as in Ramsey. The argument is organized around three philosophical theses: (i) decision theory is nothing but folk psychology stated in formal language (Lewis), (ii) the former substantially improves on (...) the latter, but is unable to overcome its typical limitations, especially its failure to separate desire and belief empirically (Davidson), (iii) the former substantially improves on the latter, and through these innovations, overcomes some of the limitations. The aim of the article is to establish (iii) not only against the all too simple thesis (i), but also against the subtle thesis (ii). (shrink)

This paper (first published under the same title in Journal of Mathematical Economics, 29, 1998, p. 331-361) is a sequel to "Consistent Bayesian Aggregation", Journal of Economic Theory, 66, 1995, p. 313-351, by the same author. Both papers examine mathematically whether the the following assumptions are compatible: the individuals and the group both form their preferences according to Subjective Expected Utility (SEU) theory, and the preferences of the group satisfy the Pareto principle with respect to those of the individuals. While (...) the 1995 paper explored these assumptions in the axiomatic context of Savage's (1954-1972) SEU theory, the present paper explores them in the context of Anscombe and Aumann's (1963) alternative SEU theory. We first show that the problematic assumptions become compatible when the Anscombe-Aumann utility functions are state-dependent and no subjective probabilities are elicited. Then we show that the problematic assumptions become incompatible when the Anscombe-Aumann utility functions are state-dependent, like before, but subjective probabilities are elicited using a relevant technical scheme. This last result reinstates the impossibilities proved by the 1995 paper, and thus shows them to be robust with respect to the choice of the SEU axiomatic framework. The technical scheme used for the elicitation of subjective probabilities is that of Karni, Schmeidler and Vind (1983). (shrink)

This paper proposes a new theory of rational choice, Expected Comparative Utility (ECU) Theory. It is first argued that for any decision option, a, and any state of the world, G, the measure of the choiceworthiness of a in G is the comparative utility of a in G – that is, the difference in utility, in G, between a and whichever alternative to a carries the greatest utility in G. On the basis of this principle, it is then argued, roughly (...) speaking, that an agent should rank her decision options (in terms of how choiceworthy they are) according to their expected comparative utility. For any decision option, a, the expected comparative utility of a is the probability-weighted average of the comparative utilities of a across the different states of the world. It is lastly demonstrated that in a number of decision cases, ECU Theory delivers different verdicts from those of standard decision theory. (shrink)

Research on preference reversals has demonstrated a disproportionate influence of outcome probability on choices between monetary gambles. The aim was to investigate the hypothesis that this is a prominence effect originally demonstrated for riskless choice. Another aim was to test the structure compatibility hypothesis as an explanation of the effect. The hypothesis implies that probability should be the prominent attribute when compared with value attributes both in a choice and a preference rating procedure. In Experiment 1, two groups of undergraduates (...) were presented with medical treatments described by two value attributes (effectiveness and pain-relief). All participants performed both a matching task and made preference ratings. In the latter task, outcome probabilities were added to the descriptions of the medical treatments for one of the groups. In line with the hypothesis, this reduced the prominence effect on the preference ratings observed for effectiveness. In Experiment 2, a matching task was used to demonstrate that probability was considered more important by a group of participating undergraduates than the value attributes. Furthermore, in both choices and preference ratings the expected prominence effect was found for probability. (shrink)

So-called money pump arguments aim to show that intransitive preferences are irrational because they will lead someone to accept a series of deals that leaves his/her financially worse off and better off in no respect. A common response to these arguments is the foresight response, which counters that the agent in question may see the exploitation coming, and refuse to trade at all. To obviate this response, I offer a “deluxe money pump argument” that applies dominance reasoning to a modified (...) money pump case. (shrink)

What are economic exchanges? The received view has it that exchanges are mutual transfers of goods motivated by inverse valuations thereof. As a corollary, the standard approach treats exchanges of services as a subspecies of exchanges of goods. We raise two objections against this standard approach. First, it is incomplete, as it fails to take into account, among other things, the offers and acceptances that lie at the core of even the simplest cases of exchanges. Second, it ultimately fails to (...) generalize to exchanges of services, in which neither inverse preferences nor mutual transfers hold true. We propose an alternative definition of exchanges, which treats exchanges of goods as a special case of exchanges of services and which builds in offers and acceptances. According to this theory: (i) The valuations motivating exchanges are propositional and convergent rather than objectual and inverse; (ii) All exchanges of goods involve exchanges of services/actions, but not the reverse; (iii) Offers and acceptances, together with the contractual obligations and claims they bring about, lie at the heart of all cases of exchange. (shrink)

Some early phase clinical studies of candidate HIV cure and remission interventions appear to have adverse medical risk–benefit ratios for participants. Why, then, do people participate? And is it ethically permissible to allow them to participate? Recent work in decision theory sheds light on both of these questions, by casting doubt on the idea that rational individuals prefer choices that maximise expected utility, and therefore by casting doubt on the idea that researchers have an ethical obligation not to enrol participants (...) in studies with high risk–benefit ratios. This work supports the view that researchers should instead defer to the considered preferences of the participants themselves. This essay briefly explains this recent work, and then explores its application to these two questions in more detail. (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 dis- tinguish 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 di¤erences, while being non- etheless empirically related to choices. We highlight the originality, promises and limits of this choice-based cardinalism. (shrink)

I have claimed that risk-weighted expected utility maximizers are rational, and that their preferences cannot be captured by expected utility theory. Richard Pettigrew and Rachael Briggs have recently challenged these claims. Both authors argue that only EU-maximizers are rational. In addition, Pettigrew argues that the preferences of REU-maximizers can indeed be captured by EU theory, and Briggs argues that REU-maximizers lose a valuable tool for simplifying their decision problems. I hold that their arguments do not succeed and that my original (...) claims still stand. However, their arguments do highlight some costs of REU theory. (shrink)

I distinguish several doctrines that economic methodologists have found attractive, all of which have a positivist flavour. One of these is the doctrine that preference assignments in economics are just shorthand descriptions of agents' choice behaviour. Although most of these doctrines are problematic, the latter doctrine about preference assignments is a respectable one, I argue. It doesn't entail any of the problematic doctrines, and indeed it is warranted independently of them.

The primary aim of this paper is the presentation of a foundation for causal decision theory. This is worth doing because causal decision theory (CDT) is philosophically the most adequate rational decision theory now available. I will not defend that claim here by elaborate comparison of the theory with all its competitors, but by providing the foundation. This puts the theory on an equal footing with competitors for which foundations have already been given. It turns out that it will also (...) produce a reply to the most serious objections made so far against CDT and against the particular version of CDT I will defend. (shrink)

Abstract: Don Ross’ Economic Theory and Cognitive Science (2005) provides an elaborate philosophical defense of neoclassical economics. He argues that the central features of neoclassical theory are associated with what he calls the Robbins-Samuelson argument pattern and that it can be reconciled with recent developments in experimental and behavioral economics, as well as contemporary cognitive science. This paper argues that Ross’ Robbins-Samuelson argument pattern is not in the work of either Robbins or Samuelson and in many ways is in conflict (...) with their own versions, and defenses, of neoclassical theory. (shrink)

Comment pouvons-nous analyser des relations de valeur non standards, comme la parité axiologique, en termes d’attitudes appropriées? Wlodek Rabinowicz suggère que deux choses sont à parité si et seulement si il est à la fois permissible de préférer l’une à l’autre et permissible d’avoir la préférence contraire. Dans un article récent, Johan Gustafsson soutient toutefois que l’analyse de Rabinowicz viole un principe de symétrie entre valeurs et préférences, selon lequel il existe pour toute relation de valeur une relation de préférence (...) correspondante (et vice-versa). À la lumière de ce principe, Gustafsson propose une analyse alternative, selon laquelle deux choses sont à parité si et seulement si il est requis d’entretenir ces choses en parité préférentielle. Dans cet article, j’examine en détail les arguments avancés par Gustafsson contre l’analyse de Rabinowicz et je montre qu’aucun d’eux n’est convaincant. (shrink)

Deliberation is often seen as the site of human freedom, but the binding power of rationality seems to imply that deliberation is, in its own way, a deterministic process. If one knows the starting preferences and circumstances of an agent, then, assuming that the agent is rational and that those preferences and circumstances don’t change, one should be in a position to predict what the agent will decide. However, given that an agent could conceivably confront equally attractive alternatives, it is (...) an open question whether rational choice theory can ever eliminate indeterminacy. The clearest support for such a limitation comes from the “Buridan’s ass” scenario, where an agent is confronted with two (or more) equally attractive/unattractive options. Does rationality by itself have the resources needed to prevent such paralysis of action? Those who cannot accept the idea of decisional impotence devise various ways to avoid it: postulating a neutral valence, tipping the utilities, positing sub-personal influences, and bunching the options. I argue that each of these responses is either unwarranted or flawed. All parties to the debate agree that, factually, paralysis of action is not a pervasive phenomenon. This is either because (i) the utilities one assigns to two or more options can never be balanced or because (ii) thanks to some non-rational faculty (say, the will), we would not be stuck even if those utilities were perfectly counterpoised. By looking critically at four untenable responses, I aim to show that (i) is often just a dogma and (ii) is by no means a silly position. (shrink)

When we ask a decision maker to express her preferences, it is typically assumed that we are eliciting a pre-existing set of preferences. However, empirical research has suggested that our preferences are often constructed on the fly for the decision problem at hand. This paper explores the ramifications of this empirical research for our understanding of instrumental rationality. First, I argue that these results pose serious challenges for the traditional decision-theoretic view of instrumental rationality, which demands global coherence amongst all (...) of one's beliefs and desires. To address these challenges, I first develop a minimal notion of instrumental rationality that issues in localized, goal-relative demands of coherence. This minimal conception of instrumental rationality is then used to offer a more sophisticated account of the global aspects of instrumental rationality. The resulting view abandons all-or-nothing assessments of rationality and allows us to evaluate decision makers as being rational to varying degrees. My aim is to propose a theory that is both psychologically and normatively plausible. (shrink)

In “The Irrelevance of the Diachronic Money-Pump Argument for Acyclicity,” The Journal of Philosophy CX, 8 (August 2013), 460-464, Johan E. Gustafsson contends that if Davidson, McKinsey and Suppes’ diachronic money-pump argument in their "Outlines of a Formal Theory of Value, I," Philosophy of Science 22 (1955), 140-160 is valid, so is the synchronic argument Gustafsson himself offers. He concludes that the latter renders irrelevant diachronic choice considerations in general, and the two best-known diachronic solutions to the money pump problem (...) in particular. I argue here that this reasoning is incorrect, and that Gustafsson’s synchronic argument is faulty on independent grounds. Specifically, it is based on a false analogy between the derivation of a synchronic ordinal ranking from a transitive series of pairwise comparisons, and the putative derivation of such a ranking from an intransitive series. The latter is not possible under the assumption of revealed preference theory, and is highly improbable even if that assumption is rejected. Moreover, Gustafsson’s argument raises issues of fidelity to the historical texts that must be addressed. I conclude that the money pump, and cyclical choice more generally, are necessarily diachronic; and therefore that the two best-known diachronic solutions to the money pump problem remain relevant. (shrink)

Orthodox decision theory gives no advice to agents who hold two goods to be incommensurate in value because such agents will have incomplete preferences. According to standard treatments, rationality requires complete preferences, so such agents are irrational. Experience shows, however, that incomplete preferences are ubiquitous in ordinary life. In this paper, we aim to do two things: (1) show that there is a good case for revising decision theory so as to allow it to apply non-vacuously to agents with incomplete (...) preferences, and (2) to identify one substantive criterion that any such non-standard decision theory must obey. Our criterion, Competitiveness, is a weaker version of a dominance principle. Despite its modesty, Competitiveness is incompatible with prospectism, a recently developed decision theory for agents with incomplete preferences. We spend the final part of the paper showing why Competitiveness should be retained, and prospectism rejected. (shrink)

This paper argues for the existence of a fourth positive generic value relation that can hold between two items beyond ‘better than’, ‘worse than’, and ‘equally good’: namely ‘on a par’.

The relations between rationality and optimization have been widely discussed in the wake of Herbert Simon's work, with the common conclusion that the rationality concept does not imply the optimization principle. The paper is partly concerned with adding evidence for this view, but its main, more challenging objective is to question the converse implication from optimization to rationality, which is accepted even by bounded rationality theorists. We discuss three topics in succession: (1) rationally defensible cyclical choices, (2) the revealed preference (...) theory of optimization, and (3) the infinite regress of optimization. We conclude that (1) and (2) provide evidence only for the weak thesis that rationality does not imply optimization. But (3) is seen to deliver a significant argument for the strong thesis that optimization does not imply rationality. (shrink)

Rational choice theory analyzes how an agent can rationally act, given his or her preferences, but says little about where those preferences come from. Preferences are usually assumed to be fixed and exogenously given. Building on related work on reasons and rational choice, we describe a framework for conceptualizing preference formation and preference change. In our model, an agent's preferences are based on certain "motivationally salient" properties of the alternatives over which the preferences are held. Preferences may change as new (...) properties of the alternatives become salient or previously salient properties cease to be salient. Our approach captures endogenous preferences in various contexts and helps to illuminate the distinction between formal and substantive concepts of rationality, as well as the role of perception in rational choice. (shrink)

According to standard rational choice theory, as commonly used in political science and economics, an agent's fundamental preferences are exogenously fixed, and any preference change over decision options is due to Bayesian information learning. Although elegant and parsimonious, such a model fails to account for preference change driven by experiences or psychological changes distinct from information learning. We develop a model of non-informational preference change. Alternatives are modelled as points in some multidimensional space, only some of whose dimensions play a (...) role in shaping the agentís preferences. Any change in these "motivationally salient" dimensions can change the agent's preferences. How it does so is described by a new representation theorem. Our model not only captures a wide range of frequently observed phenomena, but also generalizes some standard representations of preferences in political science and economics. (shrink)

The orthodox theory of instrumental rationality, expected utility (EU) theory, severely restricts the way in which risk-considerations can figure into a rational individual's preferences. It is argued here that this is because EU theory neglects an important component of instrumental rationality. This paper presents a more general theory of decision-making, risk-weighted expected utility (REU) theory, of which expected utility maximization is a special case. According to REU theory, the weight that each outcome gets in decision-making is not the subjective probability (...) of that outcome; rather, the weight each outcome gets depends on both its subjective probability and its position in the gamble. Furthermore, the individual's utility function, her subjective probability function, and a function that measures her attitude towards risk can be separately derived from her preferences via a Representation Theorem. This theorem illuminates the role that each of these entities plays in preferences, and shows how REU theory explicates the components of instrumental rationality. (shrink)

This paper critically reviews the arguments supporting rational genuine satisficing. The deconstructive effort unearths inherent problems with the position in both static and dynamic contexts. Many of these arguments build on Herbert Simon’s canonical arguments surrounding incommensurability and demandingness problems. Optimizing is re-constructed using the principles of instrumental satisficing to answer these charges. The resulting conception is both obviously undemanding and a recognizable response to focused decision making.

Decision theory has at its core a set of mathematical theorems that connect rational preferences to functions with certain structural properties. The components of these theorems, as well as their bearing on questions surrounding rationality, can be interpreted in a variety of ways. Philosophy’s current interest in decision theory represents a convergence of two very different lines of thought, one concerned with the question of how one ought to act, and the other concerned with the question of what action consists (...) in and what it reveals about the actor’s mental states. As a result, the theory has come to have two different uses in philosophy, which we might call the normative use and the interpretive use. It also has a related use that is largely within the domain of psychology, the descriptive use. This essay examines the historical development of decision theory and its uses; the relationship between the norm of decision theory and the notion of rationality; and the interdependence of the uses of decision theory. (shrink)

There is a surprising disconnect between formal rational choice theory and philosophical work on reasons. The one is silent on the role of reasons in rational choices, the other rarely engages with the formal models of decision problems used by social scientists. To bridge this gap, we propose a new, reason-based theory of rational choice. At its core is an account of preference formation, according to which an agent’s preferences are determined by his or her motivating reasons, together with a (...) ‘weighing relation’ between different combinations of reasons. By explaining how someone’s preferences may vary with changes in his or her motivating reasons, our theory illuminates the relationship between deliberation about reasons and rational choices. Although primarily positive, the theory can also help us think about how those preferences and choices ought to respond to normative reasons. (shrink)

If one can get the targets of one's current wants only by acquiring new wants (as in the Prisoner's Dilemma), is it rational to do so? Arguably not. For this could justify adopting unsatisfiable wants, violating the rational duty to maximize one's utility. Further, why cause a want's target if one will not then want it? And people "are" their wants. So if these change, people will not survive to enjoy their wants' targets. I reply that one rationally need not (...) advance one's future wants, only current ones. Furthermore, rational choice seeks not utility (the co-obtaining of a want and its target), but satisfaction (the eventual obtaining of what is now wanted) -- otherwise, it would be irrational to care now about what happens after one dies. Finally, persons survive "rational" changes of values. Thus reflection on the rational revision of values illuminates the conditions on personal identity and the bases and aims of rational choice. (shrink)

To the normal reasons that we think can justify one in preferring something, x (namely, that x has objectively preferable properties, or has properties that one prefers things to have, or that x's obtaining would advance one's preferences), I argue that it can be a justifying reason to prefer x that one's very preferring of x would advance one's preferences. Here, one prefers x not because of the properties of x, but because of the properties of one's having the preference (...) for x. So-revising one's preferences is rational in paradoxical choice situations like Kavka's Deterrence Paradox. I then try to meet the following objections: that this is stoicist, incoherent, bad faith; that it conflates instrumental and intrinsic value, gives wrong solutions to the problems presented by paradoxical choice situations, entails vicious regresses of value justification, falsifies value realism, makes valuing x unresponsive to x's properties, causes value conflict, conflicts with other standards of rationality, violates decision theory, counsels immorality, makes moral paradox, treats value change as voluntary, conflates first- and second-order values, is psychologically unrealistic, and wrongly presumes that paradoxical choice situations can even occur. (shrink)

I argue that Gauthier's constrained-maximizer rationality is problematic. But standard Maximizing Rationality means one's preferences are only rational if it would not maximize on them to adopt new ones. In the Prisoner's Dilemma, it maximizes to adopt conditionally cooperative preferences. (These are detailed, with a view to avoiding problems of circularity of definition.) Morality then maximizes. I distinguish the roles played in rational choices and their bases by preferences, dispositions, moral and rational principles, the aim of rational action, and rational (...) decision rules. I argue that Maximizing Rationality necessarily structures conclusive reasons for action. Thus conations of any sort can base rational choices only if the conations are structured like a coherent preference function; rational actions maximize on such functions. Maximization-constraining dispositions cannot integrate into a coherent preference function. (shrink)