Tversky and Koehler's support theory attempts to explain why probability judgments are affected by the manner in which formally similar events are described. Support theory suggests that as the explicitness of a description increases, an event will be judged to be more likely. In the present experiment, experienced decision-makers from large, international accounting firms were given case-specific information about an audit client and asked to provide a series of judgments regarding the perceived likelihood of events. Unpacking a (...) hypothesis into four formally equivalent hypotheses more than doubled its perceived likelihood. These results are largely consistent with support theory, extending its generalizability to applied contexts involving business professionals. Further, the paper finds that task-specific factors, a previously untested area, can also affect support theory interpretations. (shrink)

We studied how people attribute action outcomes to their own actions under conditions of uncertainty. Participants chose between left and right keypresses to produce an action effect , while a computer player made a simultaneous keypress decision. In each trial, a random generator determined which of the players controlled the action effect at varying probabilities, and participants then judged which player had produced it. Participants’ effect control ranged from 20% to 80%, varied blockwise, and they could use trial-by-trial feedback to (...) optimize the accuracy of their agency judgments. Participants tended to attribute action effects to themselves , probably reflecting a rational guessing strategy of always naming the more likely player. However, participants systematically neglected information favoring the computer player as the agent, even under conditions where this bias could only harm judgment accuracy. We conclude that agency biases have both rational and irrational components. (shrink)

Research suggests that moral evaluations change during adulthood. Older adults (75+) tend to judge accidentally harmful acts more severely than younger adults do, and this age‐related difference is in part due to the greater negligence older adults attribute to the accidental harmdoers. Across two studies (N = 254), we find support for this claim and report the novel discovery that older adults’ increased attribution of negligence, in turn, is associated with a higher perceived likelihood that the accident would occur. We (...) propose that, because older adults perceive accidents as more likely than younger adults do, they condemn the agents and their actions more and even infer that the agents’ omission to exercise due care is intentional. These findings refine our understanding of the cognitive processes underpinning moral judgment in older adulthood and highlight the role of subjective probability judgments in negligence attribution. (shrink)

Probabilistic reasoning is heavily investigated in decision research. Violations of probability theory have been demonstrated numerously, for instance, the tendency to overestimate the joint probab...

Nonmonotonic reasoning is often claimed to mimic human common sense reasoning. Only a few studies, though, investigated this claim empirically. In the present paper four psychological experiments are reported, that investigate three rules of system p, namely the and, the left logical equivalence, and the or rule. The actual inferences of the subjects are compared with the coherent normative upper and lower probability bounds derived from a non-infinitesimal probability semantics of system p. We found a relatively good agreement (...) of human reasoning and principles of nonmonotonic reasoning according to the coherence interpretation of system p. Contrary to the results reported in the “heuristics and biases” tradition, the subjects committed relatively few upper bound violations (conjunction fallacies). More lower than upper bound violations were observed. When the premises were presented in terms of intervals higher mean lower bounds were observed as when the premises were presented in terms of point percentages. (shrink)

Subjects in experiments use real-life strategies that differ significantly from those assumed by experimenters. First, true randomness is rare in both natural and constructed environments. Second, communication follows conventions which depend on the game-theoretic aspects of situations. Third, in the common rhetorical stance of storytelling, people do not tell about the representative but about unusual, exceptional, and rare cases.

Multiple epistemological programs make use of intuitive judgments pertaining to an individual’s ability to gain knowledge from exclusively probabilistic/statistical information. This paper argues that these judgments likely form without deference to such information, instead being a function of the degree to which having knowledge is representative of an agent. Thus, these judgments fit the pattern of formation via a representativeness heuristic, like that famously described by Kahneman and Tversky to explain similar probabilistic judgments. Given this broad (...) insensitivity to probabilistic/statistical information, it directly follows that these epistemic judgments are insensitive to a given agent’s epistemic status. From this, the paper concludes that, breaking with common epistemological practice, we cannot assume that such judgments are reliable. (shrink)

In this paper, we use an experimental design to compare the performance of elicitation rules for subjective beliefs. Contrary to previous works in which elicited beliefs are compared to an objective benchmark, we consider a purely subjective belief framework. The performance of different elicitation rules is assessed according to the accuracy of stated beliefs in predicting success. We measure this accuracy using two main factors: calibration and discrimination. For each of them, we propose two statistical indexes and we compare the (...) rules’ performances for each measurement. The matching probability method provides more accurate beliefs in terms of discrimination, while the quadratic scoring rule reduces overconfidence and the free rule, a simple rule with no incentives, which succeeds in eliciting accurate beliefs. Nevertheless, the matching probability appears to be the best mechanism for eliciting beliefs due to its performances in terms of calibration and discrimination, but also its ability to elicit consistent beliefs across measures and across tasks, as well as its empirical and theoretical properties. (shrink)

Richard Jeffrey is beyond dispute one of the most distinguished and influential philosophers working in the field of decision theory and the theory of knowledge. His work is distinctive in showing the interplay of epistemological concerns with probability and utility theory. Not only has he made use of standard probabilistic and decision theoretic tools to clarify concepts of evidential support and informed choice, he has also proposed significant modifications of the standard Bayesian position in order that it provide a (...) better fit with actual human experience. Probability logic is viewed not as a source of judgment but as a framework for explaining the implications of probabilistic judgments and their mutual compatability. This collection of essays spans a period of some 35 years and includes what have become some of the classic works in the literature. There is also one completely new piece, while in many instances Jeffrey includes afterthoughts on the older essays. (shrink)

Recognizing that probability (the Greek doxa) was understood in pre-modern theories as the polar opposite of certainty (episteme), the author of this study elaborates the forms which these polar opposites have taken in some twentieth century writers and then, in greater detail, in the writings of Thomas Aquinas. Profiting from subsequent more sophisticated theories of probability, he examines how Aquinas’s judgments about everything from God to gossip depend on schematizations of the polarity between the systematic and the (...) non-systematic: revelation/reason, science/opinion, saints/philosophers, Aristotle/others. Post-medieval developments have provided the means to discern within Thomas’s thought both a logical theory and a kind of relative frequency theory of probability. The former depends on Aristotle’s theory of demonstration, the latter on his theory of an orderly cosmos; but each as used by Thomas lead to convictions that are sometimes naive, sometimes amusing or even terrifying. (shrink)

Suppose a rational agent S has some evidence E that bears on p, and on that basis makes a judgment about p. For simplicity, we’ll normally assume that she judges that p, though we’re also interested in cases where the agent makes other judgments, such as that p is probable, or that p is well-supported by the evidence. We’ll also assume, again for simplicity, that the agent knows that E is the basis for her judgment. Finally, we’ll assume that (...) the judgment is a rational one to make, though we won’t assume the agent knows this. Indeed, whether the agent can always know that she’s making a rational judgment when in fact she is will be of central importance in some of the debates that follow. (shrink)

Generics and frequency statements are puzzling phenomena: they are lawlike, yet contingent. They may be true even in the absence of any supporting instances, and extending the size of their domain does not change their truth conditions. Generics and frequency statements are parametric on time, but not on possible worlds; they cannot be applied to temporary generalizations, and yet are contingent. These constructions require a regular distribution of events along the time axis. Truth judgments of generics vary considerably across (...) speakers, whereas truth judgments of frequency statements are much more uniform. A generic may be false even if the vast majority of individuals in its domain satisfy the predicated property, whereas a frequency statement using, e.g., usually would be true. This paper argues that all these seemingly unrelated puzzles have a single underlying cause: generics and frequency statements express probability judgments, and these, in turn, are interpreted as statements of hypothetical relative frequency. (shrink)

Many groups make decisions over multiple interconnected propositions. The “doctrinal paradox” or “discursive dilemma” shows that propositionwise majority voting can generate inconsistent collective sets of judgments, even when individual sets of judgments are all consistent. I develop a simple model for determining the probability of the paradox, given various assumptions about the probability distribution of individual sets of judgments, including impartial culture and impartial anonymous culture assumptions. I prove several convergence results, identifying when the (...) class='Hi'>probability of the paradox converges to 1, and when it converges to 0, as the number of individuals increases. Drawing on the Condorcet jury theorem and work by Bovens and Rabinowicz , I use the model to assess the “truth-tracking” performance of two decision procedures, the premise- and conclusion-based procedures. I compare the present results with existing results on the probability of Condorcet’s paradox. I suggest that the doctrinal paradox is likely to occur under plausible conditions. (shrink)

This paper seeks to defend the following conclusions: The program advanced by Carnap and other necessarians for probability logic has little to recommend it except for one important point. Credal probability judgments ought to be adapted to changes in evidence or states of full belief in a principled manner in conformity with the inquirer’s confirmational commitments—except when the inquirer has good reason to modify his or her confirmational commitment. Probability logic ought to spell out the constraints (...) on rationally coherent confirmational commitments. In the case where credal judgments are numerically determinate confirmational commitments correspond to Carnap’s credibility functions mathematically represented by so—called confirmation functions. Serious investigation of the conditions under which confirmational commitments should be changed ought to be a prime target for critical reflection. The necessarians were mistaken in thinking that confirmational commitments are immune to legitimate modification altogether. But their personalist or subjectivist critics went too far in suggesting that we might dispense with confirmational commitments. There is room for serious reflection on conditions under which changes in confirmational commitments may be brought under critical control. Undertaking such reflection need not become embroiled in the anti inductivism that has characterized the work of Popper, Carnap and Jeffrey and narrowed the focus of students of logical and methodological issues pertaining to inquiry. (shrink)

There is a vast literature that seeks to uncover features underlying moral judgment by eliciting reactions to hypothetical scenarios such as trolley problems. These thought experiments assume that participants accept the outcomes stipulated in the scenarios. Across seven studies, we demonstrate that intuition overrides stipulated outcomes even when participants are explicitly told that an action will result in a particular outcome. Participants instead substitute their own estimates of the probability of outcomes for stipulated outcomes, and these probability estimates (...) in turn influence moral judgments. Our findings demonstrate that intuitive likelihoods are one critical factor in moral judgment, one that is not suspended even in moral dilemmas that explicitly stipulate outcomes. Features thought to underlie moral reasoning, such as intention, may operate, in part, by affecting the intuitive likelihood of outcomes, and, problematically, moral differences between scenarios may be confounded with non-moral intuitive probabilities. (shrink)

Illuminates legal reasoning -- and its justification At least since plato and Aristotle, thinkers have pondered the relationship between philosophical arguments and the "sophistical" arguments offered by the Sophists -- who were the first professional lawyers. Judges wield substantial political power, and the justifications they offer for their decisions are a vital means by which citizens can assess the legitimacy of how that power is exercised. However, to evaluate judicial justifications requires close attention to the method of reasoning behind decisions. (...) This new collection illuminates and explains the political and moral importance in justifying the exercise of judicial power. Explores enduring questions Focusing on work over the past century, the essays address important recurring questions, such as: When a judge or a lawyer reasons to a conclusion about what is legally required in a given case, must he also ask what is morally required? To what extent do a judge's personal, political, or moral biases affect his legal reasoning? What is the impact of such biases? Can all such biases be avoided? Is legal reasoning similar to reasoning in mathematics, logic, and linguistics, the physical sciences, the social sciences, or literature and history? Do formal logical modes of argument play any roles in legal reasoning? Solid coverage, well organized The articles were chosen to present some of the most influential works on the topic, as well as less familiar works that are thought provoking and informative. Each volume also offers a representative range of theoretical approaches to its topic, contains an introduction that locates the subject within the larger framework oftheories of legal reasoning and jurisprudence, and includes bibliographical notes on further readings. Many 19th century legal theorists argued that deduction is the central mode of legal reasoning, and that legal argument is like a deductive proof in mathematics or logic. They were attracted to this "deductivist" concept because it suggested that legal reasoning could be politically and morally neutral. This volume brings together some of the most thought-provoking articles on both sides of the debate. It also contains several leading articles that explain the role of probabilistic judgments and presumptions in various types of legal arguments, including the laws of evidence and criminal procedure. The collection is a solid introduction to the basic modes of logical argument in legal reasoning. (shrink)

Moral considerations and our normative expectations influence not only our judgments about intentional action or causation but also our judgments about exact probabilities and quantities. Whereas those cases support the competence theory proposed by Knobe in his paper, they remain compatible with a modular conception of the interaction between moral and nonmoral cognitive faculties in each of those domains.

Inductive reasoning requires exploiting links between evidence and hypotheses. This can be done focusing either on the posterior probability of the hypothesis when updated on the new evidence or on the impact of the new evidence on the credibility of the hypothesis. But are these two cognitive representations equally reliable? This study investigates this question by comparing probability and impact judgments on the same experimental materials. The results indicate that impact judgments are more consistent in time (...) and more accurate than probability judgments. Impact judgments also predict the direction of errors in probability judgments. These findings suggest that human inductive reasoning relies more on estimating evidential impact than on posterior probability. (shrink)

Beginning with an analysis of the "reluctant gambler problem"—in which the notion of guiding one's life by probability seems to conflict with the preferences of rational people—we draw a distinction between rule and act probabilism. Arguing that humans are rule probabilists by default, we show that reluctant gamblers can be viewed as rule probabilists. If so viewed, their reluctance to gamble is consistent with their rational use of probability judgments to guide their lives.The distinction between rule and (...) act probabilism suggests a way to analyze the risks stemming from the September 11 terrorist attacks. Assessing the risks posed by the new reality of terrorism in the U.S. in light of the rule versus act probabilist distinction shows the risks Americans face from a terrorist attack are essentially the same as they were before September 11, 2002. Yet empirical investigation indicates Americans exaggerate their personal risks from terrorism.The perception that the risks of terrorism mushroomed on September 11 is partially explained by the 24-hour news stations' TV coverage and the current administration's "interest" in diverting attention from their own questionable practices. While the risks of terrorism are not appreciably higher than they were prior to September 11, they might be further reduced. Unfortunately, our government's strategy to reduce the risks of terrorist strikes involves weakening the Constitution. Americans face the question how much it is appropriate to pay—in diminished rights and liberties—to reduce a risk that is essentially the same as it was prior to the attacks. (shrink)

Day argues that the meaning of "probable" is partly evaluative and partly descriptive--to say that a proposition is probable is both to recommend its assertion and to say that a certain procedure shows it to be so. The paradigm of an inductive probability judgment, which is the major concern of the book, is "The fact that all observed A's are B's makes it probable that all A's are B's." Several more complex kinds of probability judgments are distinguished (...) and discussed in detail, the author's own theory being illuminated by extensive criticism of the views of other philosophers, including Aristotle, Hume, Whewell, Mill, Peirce, Russell, Braithwaite, Carnap, and Von Wright. Philosophic problems related to induction, such as the existence of other minds and the reliability of memory, are briefly discussed. Ambitious in scope and carefully executed, the book demands, and rewards, close study.--J. R. W. (shrink)

Cognitive biases that affect decision making may affect the decisions of citizens that influence public policy. To the extent that decisions follow principles other than maximizing utility for all, it is less likely that utility will be maximized, and the citizens will ultimately suffer the results. Here I outline some basic arguments concerning decisions by citizens, using voting as an example. I describe two types of values that may lead to sub-optimal consequences when these values influence political behavior: moralistic values (...) (which people are willing to impose on others regardless of the consequences) and protected values (PVs, values protected from trade-offs). I present evidence against the idea that voting is expressive, i.e., that voters aim to express their moral views rather than to have an effect on outcomes. I show experimentally that PVs are often moralistic. Finally, I present some data that citizens’ think of their duty in a parochial way, neglecting out-groups. I conclude that moral judgments are important determinants of citizen behavior, that these judgments are subject to biases and based on moralistic values, and that, therefore, outcomes are probably less good than they could be. (shrink)

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)

From a point of view like de Finetti's, what is the judgmental reality underlying the objectivistic claim that a physical magnitude X determines the objective probability that a hypothesis H is true? When you have definite conditional judgmental probabilities for H given the various unknown values of X, a plausible answer is sufficiency, i.e., invariance of those conditional probabilities as your probability distribution over the values of X varies. A different answer, in terms of conditional exchangeability, is offered (...) for use when such definite conditional probabilities are absent. (shrink)

Previous research on moral dilemmas has mainly focused on decisions made under conditions of probabilistic certainty. We investigated the impact of uncertainty on the preference for action (killing one individual to save five people) and inaction (saving one but allowing five people to die) in moral dilemmas. We reported two experimental studies that varied the framing (gain vs loss), levels of risk (probability of gain and loss) and levels of ambiguity (imprecise probability information) in the choice to save (...) five individuals by sacrificing one. We found that participants preferred actions with uncertainty (risk/ambiguity) over inaction. Specifically, we found that participants preferred actions with precise probability information (risk) over inaction, and they preferred actions with modest or high levels of ambiguity over actions with precise probabilities, especially when moral dilemmas had a loss frame. We also observed commission bias in Study 2. We discussed the implications for research in moral decision-making. (shrink)

SummaryA special theory of probability is propounded as a non‐deductive supplement to analytic judgments in epistemological systems. This theory combines ‘inductive’ probability and ‘effective’ probability in a total probability which is the ‘degree of certainty’ of our beliefs. For cases of false belief, the concept of ‘degree of credibility’, or assumed degree of certainty, is introduced. This quantity is mathematically combined with the ‘real’ degree of certainty to determine the flower) degree of certainty implicit in (...) a mistaken credence.RésuméUne théorie spéciale de la probabilité comme supplément non déductif des jugements analytiques en systèmes épistémologiques est proposée. Cette théorie combine la probabilité‘inductive’ et la probabilité‘effective’ dans une probabilité totale qui est le ‘degré de certitude’ de nos croyances. Pour les cas de fausse croyance, le concept de ‘degré de crédibilité’, ou degrésupposé de certitude, est introduit. Cette quantité est mathématiquement combinée avec le degré‘réel’ de certitude pour déterminer le degré de certitude implicite dans une croyance erronée.ZusammenfassungEine besondere Wahrscheinlichkeitstheorie wird vorgeschlagen als eine nichtdeduktive Ergänzung der analytischen Urteile in erkenntnistheoretischen Systemen. Diese Theorie kombiniert die 〈induktive〉 Wahrscheinlichkeit mit der 〈effektiven〉 Wahrscheinlichkeit , indem sie sie zu einer totalen Wahrscheinlichkeit verbindet, die den 〈Grad der Gewissheit〉 unseres Glaubens ausmacht. Der Begriff des 〈Grades der Glaubwiirdigkeit〉, oder der angenommene Gewissheitsgrad, wird für Falle von falschem Glauben eingeführt. Diese Quantität wird mathematisch mit dem 〈wirklichen〉 Gewissheitsgrad kombiniert, um den Gewissheitsgrad, der implizit in falschen Erwartungen vorhanden ist, zu bestimmen. (shrink)

Merchant and Rockness (1994, p. 92) characterize earnings management as "probably the most important ethical issue facing the accounting profession" and provide initial evidence of the ethical judgments of various organizational members. The current study extends their work by examining the extent to which an individual''s ethically-related judgments in response to earnings management activities are associated with the individual''s role.In an experimental study, evening MBA students read three hypothetical scenarios involving a manager engaging in earnings management. The scenarios (...) involved a gain from an operating activity, a gain from an accounting activity, and a loss from an accounting activity. Before reading the cases, however, participants were randomly assigned to one of three roles: a shareholder, another manager from the company who is unfamiliar with the manager in the case, or another manager from the company who is familiar with the manager in the case. Following each case, participants made four ethically related judgments. (shrink)

Explanation is a central concept in human psychology. Drawing upon philosophical theories of explanation, psychologists have recently begun to examine the relationship between explanation, probability and causality. Our study advances this growing literature in the intersection of psychology and philosophy of science by systematically investigating how judgments of explanatory power are affected by the prior credibility of a potential explanation, the causal framing used to describe the explanation, the generalizability of the explanation, and its statistical relevance for the (...) evidence. Collectively, the results of our five experiments support the hypothesis that the prior credibility of a causal explanation plays a central role in explanatory reasoning: first, because of the presence of strong main effects on judgments of explanatory power, and second, because of the gate-keeping role it has for other factors. Highly credible explanations were not susceptible to causal framing effects. Instead, highly credible hypotheses were sensitive to the effects of factors which are usually considered relevant from a normative point of view: the generalizability of an explanation, and its statistical relevance for the evidence. These results advance current literature in the philosophy and psychology of explanation in three ways. First, they yield a more nuanced understanding of the determinants of judgments of explanatory power, and the interaction between these factors. Second, they illuminate the close relationship between prior beliefs and explanatory power. Third, they clarify the relationship between abductive and probabilistic reasoning. (shrink)

My focus is on aggregation of individual value rankings of alternatives to a collective value ranking. This is compared with aggregation o individual prefrences to a collective preference. While in an individual preference ranking the alternatives are ordered in accordance with one’s preferences, the order in a value ranking expresses one’s comparative evaluation of the alternatives, from the best to the worst. I suggest that, despite their formal similarity as rankings, this difference in the nature of individual inputs in two (...) aggregation scenarios has important implications: The kind of procedure that looks fine for aggregation of judgments is inappropriate for aggregation of preferences. The procedure I have in mind consists in similarity maximization, or – more precisely – in minimization of the average distance from individual inputs. When applied to judgment aggregation, this procedure can also be approached from the epistemic perspective: the questions are posed concerning its advantages as a truth-tracker. From that perspective, what matters is not only the probability of the outcome of the procedure being true, but also the expected verisimilitude of the outcome: its expected distance from truth. (shrink)

Making up your mind can include making up your mind about how to change your mind. Here a suggestion for coding imputations of influence into the kinematics of judgmental probabilities is applied to the treatment of Newcomb problems in The Logic of Decision framework. The suggestion is that what identifies you as treating judgmental probabilistic covariance of X and Y as measuring an influence of X on Y is constancy of your probabilities for values of Y conditionally on values of (...) X as your judgmental probability distribution for values of X changes. (shrink)

Cognitive biases that affect decision making may affect the decisions of citizens that influence public policy. To the extent that decisions follow principles other than maximizing utility for all, it is less likely that utility will be maximized, and the citizens will ultimately suffer the results. Here I outline some basic arguments concerning decisions by citizens, using voting as an example. I describe two types of values that may lead to sub-optimal consequences when these values influence political behavior: moralistic values (...) (which people are willing to impose on others regardless of the consequences) and protected values (PVs, values protected from trade-offs). I present evidence against the idea that voting is expressive, i.e., that voters aim to express their moral views rather than to have an effect on outcomes. I show experimentally that PVs are often moralistic. Finally, I present some data that citizens’ think of their duty in a parochial way, neglecting out-groups. I conclude that moral judgments are important determinants of citizen behavior, that these judgments are subject to biases and based on moralistic values, and that, therefore, outcomes are probably less good than they could be. (shrink)