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AbstractOne of the most debated topics among those who study heuristics is the question of their rationality. The present paper proposes an answer to this question based on the ideas of instrumental rationality and the probabilistic nature of heuristic judgments and decisions. Accordingly, it is argued that the rationality of heuristics is determined by their effectiveness, i.e., their ability to achieve a desired result. At the same time, heuristics do not always produce such a result, but only in a certain number of cases. Therefore, their effectiveness should not be evaluated by the binary logic criterion (effective/ineffective) but by the probabilistic criterion, i.e., by how often they lead to the desired result. Each heuristic has a certain objective probability of achieving such a result, which determines its rationality. However, this probability is mostly unknown to us, so when relying on heuristics, we are likely guided by a subjective perception of it, which serves as a metacognitive cue about the probability of the conclusion obtained with the help of this heuristic. [ABSTRACT FROM AUTHOR]

AbstractThis paper discusses the engagement of economists with the issue of the measurability of uncertainty. After a summary of the meaning attributed by authors such as Knight, Keynes, Shackle and Ellsberg to the contention that uncertainty is irreducible to risk and therefore unmeasurable, the paper investigates why this view did not emerge as a significant alternative to the mainstream up until recently. A main reason, never openly discussed in the literature, is shown to be the close link between Leonard Savage and the group of decision theorists at the Cowles Commission under the directorship of Jacob Marschak and Tjalling Koopmans. The paper aims to show that Koopmans, in particular, had a significant role in convincing economists that Savage’s axiomatization of a subjective version of expected utility was a decisive advance in the definition of rational behaviour. [ABSTRACT FROM AUTHOR]

Risky decision-making (RDM) is when individuals make choices based on the definite cognition for the probabilities of the options. Risk is embodied in the certainty of reward, and the smaller the probability is, the greater the risk will be. As simulated in human behavior paradigms, RDM scenarios in real life are often guided by external cues that inform the likelihood of receiving certain rewards. There are few studies on the neural basis of RDM behavior guided by external cues, which is related to the relative paucity of the animal behavioral paradigms. Here, we established a cue-guided RDM task to detect the behavior of rats making a decision between a small certain reward and a large uncertain reward in a naturalistic manner. The reward of the risk option could be adjusted to observe the change of choice. Our results showed that: (1) rats were able to master the operation of the cue-guided RDM task; (2) many rats were inclined to choose risk rather than the safe option when the reward expectations were equal; (3) rats were able to adjust the decision strategy in time upon a change in risk, suggesting that they have the ability to perceive risk indicated by the external cues. [ABSTRACT FROM AUTHOR]

Individual preferences for the flavor of different foods and fluids exert a strong influence on behavior. Most current theories posit that preferences are integrated with other state variables in the orbitofrontal cortex (OFC), which is thought to derive the relative subjective value of available options to guide choice behavior. Here, we report that instead of a single integrated valuation system in the OFC, another complementary one is centered in the ventrolateral prefrontal cortex (vlPFC) in macaques. Specifically, we found that the OFC and vlPFC preferentially represent outcome flavor and outcome probability, respectively, and that preferences are separately integrated into value representations in these areas. In addition, the vlPFC, but not the OFC, represented the probability of receiving the available outcome flavors separately, with the difference between these representations reflecting the degree of preference for each flavor. Thus, both the vlPFC and OFC exhibit dissociable but complementary representations of subjective value, both of which are necessary for decision-making. • Neurons in the vlPFC and OFC signal dissociable aspects of subjective value • vlPFC neurons preferentially represent the probability of receiving an outcome • OFC neurons preferentially represent outcome qualities (e.g., flavor) • Changes in preference differentially influence vlPFC and OFC representations Stoll and Rudebeck recorded the activity of more than 7,700 neurons across the ventral frontal cortex and amygdala in monkeys, revealing neuronal markers of multiple valuation systems, each integrating the animals' preferences in specific ways. [ABSTRACT FROM AUTHOR]

Background: Clinical guidelines are developed to lower risks, mostly viewed upon as probability. However, in daily practice, risk is perceived as the combination of probability and the impact of desired and adverse events. This combination of probability and impact can be visualized in a risk matrix. We evaluated the effect of interventions and diagnostic thresholds on modeled risk, by using the risk matrix approach (RMA) in a clinical guideline development process, and investigated which additional factors affected choices.Methods: To improve care outcomes, we developed new guidelines in which care professionals had to decide upon novel interventions and diagnostic thresholds. A risk matrix showed the probability and impact of an intervention, together with the corresponding risk category. First, professionals' opinion on required performance characteristics on risk were evaluated by a qualitative online survey. Second, qualitative assessment of possible additional factors affecting final decisions, that followed from group discussion and guideline development were evaluated.Results: Upfront, professionals opinioned that non-invasive interventions should decrease the general population risk, whereas invasive interventions should decrease the risk in high-risk groups. Nonetheless, when making guidelines, interventions were introduced without reaching the predefined threshold of desired risk reduction. Professionals weighed other aspects besides risk reduction, as financial aspects and practical consequences for daily practice in this guideline-making process.Conclusion: Professionals are willing to change policies at much lower level of anticipated effectiveness than defined upfront. Although objectively presented data structured group discussions, decisions in guideline development are affected by several other factors than risk reduction alone. [ABSTRACT FROM AUTHOR]

Despite the importance of uncertainty in decision-making, few published studies have examined how individuals make moral judgments under uncertainty. Across four experiments (N = 445), we examined whether a relatively small shift in probability affected participants' judgments of both moral acceptability and choice. Overall, reading dilemmas where the characters were either certain or likely to die, the probability of the sacrificed individual and the group at risk dying both had independent effects on participants' responses. That is, participants were more accepting of sacrificing the individual if they were not certain to die, but less accepting if the group was only likely to die when the individual was not sacrificed. Furthermore, a number of participants made acceptability ratings that did not match the action they endorsed, either finding the sacrificial decision more acceptable but refusing to make it, or choosing the sacrificial decision while viewing it as less acceptable. Many participants also stated that this was because they recognised a crucial difference between what they viewed as morally acceptable in a dilemma and what they were actually willing to do. Such mismatches may reflect the sensitivity and complexity of the moral principles that individuals employ during their moral decision-making. [ABSTRACT FROM AUTHOR]

Rationale: Although numerous studies have suggested that pharmacological alteration of the dopamine (DA) system modulates reward discounting, these studies have produced inconsistent findings. Objectives: Here, we conducted a systematic review and pre-registered meta-analysis to evaluate DA drug-mediated effects on reward discounting of time, probability, and effort costs in studies of healthy rats. This produced a total of 1343 articles to screen for inclusion/exclusion. From the literature, we identified 117 effects from approximately 1549 individual rats. Methods: Using random effects with maximum-likelihood estimation, we meta-analyzed placebo-controlled drug effects for (1) DA D1-like receptor agonists and (2) antagonists, (3) D2-like agonists and (4) antagonists, and (5) DA transporter-modulating drugs. Results: Meta-analytic effects showed that DAT-modulating drugs decreased reward discounting. While D1-like and D2-like antagonists both increased discounting, agonist drugs for those receptors had no significant effect on discounting behavior. A number of these effects appear contingent on study design features like cost type, rat strain, and microinfusion location. Conclusions: These findings suggest a nuanced relationship between DA and discounting behavior and urge caution when drawing generalizations about the effects of pharmacologically manipulating dopamine on reward-based decision-making. [ABSTRACT FROM AUTHOR]

The authors propose that the phonetic elements of a name affect risk perception. Specifically, they find that people prefer a name that evokes volatility when faced with a risky prospect, but prefer a name that evokes calmness when faced with a safe prospect. The authors posit that a volatile (vs. calm) prospect name results in more perceived fluctuations, and thus greater movement from, the given risk level. Therefore, a volatile prospect name results in a wider range of probabilities compared to a calm prospect name. The authors test the proposed effect and the role of the phonetic elements of a name using real-world data and controlled studies within diverse consumer domains (e.g., product evaluations, wagering, and branding). Findings contribute to the larger theoretical area of phonetic symbolism and provide guidance for practitioners trying to maximize preference for a given product, service, or policy. [ABSTRACT FROM AUTHOR]

Estimates of quantities needed to plan invasive species control, such as population size, are always uncertain; this is an issue that can become a problem when mishandled in ecological science and its communication. The complexities of incorporating uncertainty into sophisticated decision‐support tools may be a barrier to their use by decision makers, leading to decisions being made without due regard to uncertainty and risking misplaced certainty of predicted outcomes. We summarise ways in which uncertainty has been incorporated into and used to advise decisions on the management of invasive non‐native species and other problem species, and offer a simple conceptual model for accommodating and using uncertainty at the planning stage. We also demonstrate how frequently uncertainty has been misused and miscommunicated in the wildlife management literature. We contend that uncertainty in estimates of natural quantities must be acknowledged, can inform decisions and can be made to derive decisions, and should not be ignored if invasive species policy is to be delivered effectively. Uncertainty must be communicated thoroughly and correctly by scientists if decision makers are to understand its consequences for planning and resourcing control programmes. [ABSTRACT FROM AUTHOR]

Characterizing the evolution of social networks is challenging, because social networks tend to be large. In addition, their evolution entails latent variables, such as unobserved meeting states. The objective of this paper was to develop a utility-based model with preference parameters for clarifying the reasons for the behavior underlying network evolution. The expectation-maximization (EM) algorithm combined with snowball sampling (SS) was proposed for parameter estimation. EM is suitable to cope with the data set with latent variables or missing data and SS would be helpful in decreasing the network size without loss of critical information. Simulation studies were further performed to assess the effects of network size, seed set size, meeting probabilities, sampling waves, and sampling methods on the summary statistics of estimates and to highlight the importance of the unobserved variables. Finally, an application was developed on the Facebook platform to demonstrate the model. In all, the proposed model is expected to be a novel tool for exploring and understanding the evolution of social networks. [ABSTRACT FROM AUTHOR]

Introduction: Patients with Parkinson's disease (PD) are known to have decision-making impairments in tasks involving probabilistic information. How PD patients utilize task-relevant probabilistic advance information to plan and initiate common motor tasks like grasping has not yet been studied.Methods: PD patients (n = 15, OFF medication) and control participants repeatedly grasped and lifted an object, the weight of which could be light, medium, or heavy. Visual cues provided explicit probabilistic information about the upcoming weight at the start of each grip-lift trial. This information allows the force of the grasping fingers to be scaled predictively so that it matches the likely weight, with a suitable rate of initial force increase. Deterministic cues announced the upcoming weight with certainty in other grip-lift trials. In a weight adjustment experiment, participants associated each probabilistic cue with a specific heaviness.Results: The weight adjustment experiments showed that the probabilistic cues were understood correctly. However, PD patients utilized the probabilistic information significantly less than controls during the grip-lift task. Specifically, patients did not initiate their grasp more forcefully when probabilistic cues announced a high likelihood (66.7% probability) of a heavy weight, in contrast to controls. Thus, probabilistic cues that encouraged a more vigorous action had no effect in PD. Nevertheless, patients and controls scaled their forces appropriately when deterministic cues announced the forthcoming weights unambiguously.Conclusions: PD patients do not invest a high movement effort to initiate a grip-lift unless the necessity of such a vigorous action initiation is decidedly clear. [ABSTRACT FROM AUTHOR]

Abstract What role does attention play in decision-making? Prior research has demonstrated a link between visual attention and value-based choice, but the direction of causality is still unclear. Here we aimed to demonstrate that attention has a causal influence on choice. We tested whether spatially biasing attention in a visual search task would produce choice biases in a later choice task. We ran four experiments where the search target was more likely to appear on one "rich" side of the screen. In the subsequent choice tasks, participants were more likely to choose items appearing on the rich side and the average choice bias depended on how well participants learned the regularity in the search task. Additionally, eye-tracking data revealed a first-fixation bias toward the rich side, which in turn influenced choices. Taken together, these results provide novel support for a causal effect of attention on choice. [ABSTRACT FROM AUTHOR]

Cognitive psychologists are familiar with how their expertise in understanding human perception, memory, and decision-making is applicable to the justice system. They may be less familiar with how their expertise in statistical decision-making and their comfort working in noisy real-world environments is just as applicable. Here we show how this expertise in ideal-observer models may be leveraged to calculate the probability of guilt of Gary Leiterman, a man convicted of murder on the basis of DNA evidence. We show by common probability theory that Leiterman is likely a victim of a tragic contamination event rather than a murderer. Making any calculation of the probability of guilt necessarily relies on subjective assumptions. The conclusion about Leiterman’s innocence is not overly sensitive to the assumptions—the probability of innocence remains high for a wide range of reasonable assumptions. We note that cognitive psychologists may be well suited to make these calculations because as working scientists they may be comfortable with the role a reasonable degree of subjectivity plays in analysis. [ABSTRACT FROM AUTHOR]

What role does attention play in decision-making? Prior research has demonstrated a link between visual attention and value-based choice, but the direction of causality is still unclear. Here we aimed to demonstrate that attention has a causal influence on choice. We tested whether spatially biasing attention in a visual search task would produce choice biases in a later choice task. We ran four experiments where the search target was more likely to appear on one "rich" side of the screen. In the subsequent choice tasks, participants were more likely to choose items appearing on the rich side and the average choice bias depended on how well participants learned the regularity in the search task. Additionally, eye-tracking data revealed a first-fixation bias toward the rich side, which in turn influenced choices. Taken together, these results provide novel support for a causal effect of attention on choice. [ABSTRACT FROM AUTHOR]

A great deal of current research on moral judgments centers on moral dilemmas concerning tradeoffs between one and five lives. Whether one considers killing one innocent person to save five others to be morally required or impermissible has been taken to determine whether one is appealing to consequentialist or non-consequentialist reasoning. But this focus on tradeoffs between one and five may obscure more nuanced commitments involved in moral decision-making that are revealed when the numbers and ratio of lives to be traded off are varied, and when the probabilities of each outcome occurring are less than certain. Four studies examine participants' reactions to scenarios that diverge in these ways from the standard ones. Study 1 examines the extent to which people are sensitive to the ratio of lives saved to lives ended by a particular action. Study 2 verifies that the ratio rather than the difference between the two values is operative. Study 3 examines whether participants treat probabilistic harm to some as equivalent to certainly harming fewer, holding expected ratio constant. Study 4 explores an analogous issue regarding the sensitivity of probabilistic saving. Participants are remarkably sensitive to expected ratio for probabilistic harms while deviating from expected value for probabilistic saving. Collectively, the studies provide evidence that people's moral judgments are consistent with the principle of threshold deontology. [ABSTRACT FROM AUTHOR]

The ability to calculate precise likelihood ratios is fundamental to science, from Quantum Information Theory through to Quantum State Estimation. However, there is no assumption-free statistical methodology to achieve this. For instance, in the absence of data relating to covariate overlap, the widely used Bayes' theorem either defaults to the marginal probability driven 'naive Bayes' classifier', or requires the use of compensatory expectation-maximization techniques. This paper takes an information-theoretic approach in developing a new statistical formula for the calculation of likelihood ratios based on the principles of quantum entanglement, and demonstrates that Bayes' theorem is a special case of a more general quantum mechanical expression. [ABSTRACT FROM AUTHOR]

The critical literature on Keynes has provided extensive analysis of why individual agents may find convenient to adopt a “conventionaljudgement”, and what he meant by “polite techniques” used to save their faces as “rational, economic men.” This paper concentrates instead on impolite techniques of thought suited to deal with Keynesian uncertainty. The paper suggests that the thread going from Keynes'sTreatise on Probabilityto theGeneral Theoryand its defence provides a positive analysis of decision-making under uncertainty, and that placing emphasis on this positive analysis simply means adhering to Keynes's long-standing commitment to a (surely peculiar) probabilistic set-up. [ABSTRACT FROM PUBLISHER]

Structural systems are under deterioration due to ageing, mechanical stressors, and harsh environment, among other threats. Corrosion and fatigue can cause gradual structural deterioration. Moreover, natural and man-made hazards may lead to a sudden drop in the structural performance. Inspection and maintenance actions are performed to monitor the structural safety and maintain the performance over certain thresholds. However, these actions must be effectively planned throughout the life-cycle of a system to ensure the optimum budget allocation and maximum possible service life without adverse effects on the structural system safety. Life-cycle engineering provides rational means to optimise life-cycle aspects, starting from the initial design and construction to dismantling and replacing the system at the end of its service life. This paper presents a brief overview of the recent research achievements in the field of life-cycle engineering for civil and marine structural systems and indicates future directions in this research field. Several aspects of life-cycle engineering are presented, including the performance prediction under uncertainty and optimisation of life-cycle cost and intervention activities, as well as the role of structural health monitoring and non-destructive testing techniques in supporting the life-cycle management decisions. Risk, resilience, sustainability, and their integration into the life-cycle management are also discussed. [ABSTRACT FROM PUBLISHER]

Rationale: Studies employing the Iowa Gambling Task (IGT) demonstrated that areas of the frontal cortex, including the ventromedial prefrontal cortex, orbitofrontal cortex (OFC), dorsolateral prefrontal cortex, and anterior cingulate cortex (ACC), are involved in the decision-making process. However, the precise role of these regions in maintaining optimal choice is not clear. Objectives: We used the rat gambling task (rGT), a rodent analogue of the IGT, to determine whether inactivation of or altered dopamine signalling within discrete cortical sub-regions disrupts decision-making. Methods: Following training on the rGT, animals were implanted with guide cannulae aimed at the prelimbic (PrL) or infralimbic (IL) cortices, the OFC, or the ACC. Prior to testing, rats received an infusion of saline or a combination of baclofen and muscimol (0.125 μg of each/side) to inactivate the region and an infusion of a dopamine D2 receptor antagonist (0, 0.1, 0.3, and 1.0 μg/side). Results: Rats tended to increase their choice of a disadvantageous option and decrease their choice of the optimal option following inactivation of either the IL or PrL cortex. In contrast, OFC or ACC inactivation did not affect decision-making. Infusion of a dopamine D2 receptor antagonist into any sub-region did not alter choice preference. Conclusions: Online activity of the IL or PrL cortex is important for maintaining an optimal decision-making strategy, but optimal performance on the rGT does not require frontal cortex dopamine D2 receptor activation. Additionally, these results demonstrate that the roles of different cortical regions in cost-benefit decision-making may be dissociated using the rGT. [ABSTRACT FROM AUTHOR]

The Monty Hall dilemma (MHD) is a notorious probability problem with a counterintuitive solution. There is a strong tendency to stay with the initial choice, despite the fact that switching doubles the probability of winning. The current randomised experiment investigates whether feedback in a series of trials improves behavioural performance on the MHD and increases the level of understanding of the problem. Feedback was either conditional or non-conditional, and was given either in frequency format or in percentage format. Results show that people learn to switch most when receiving conditional feedback in frequency format. However, problem understanding does not improve as a consequence of receiving feedback. Our study confirms the dissociation between behavioural performance on the MHD, on one hand, and actual understanding of the MHD, on the other. We discuss how this dissociation can be understood. [ABSTRACT FROM AUTHOR]

The standards for expressions of evaluative opinions in the forensic sciences are increasingly being challenged and refined. Where once categorical statements regarding the origin of a trace were standard practice, criminalists are now being encouraged to represent the uncertainty associated with their inferential process by using numerical or verbal likelihood ratios. Although there are valid reasons to support this shift, the approach is not without limitations. Decades of psychological research investigating the interpretation and integration of probabilistic expressions, and the equivalence of verbal and numerical formulations for uncertainty, reveals a disconnect between what is intended by experts and what is understood by decision-makers. In this paper we present an indicative review of the psychological evidence to foster communication and collaboration between forensic scientists and psychologists and reduce instances of miscommunication in our criminal justice system. [ABSTRACT FROM PUBLISHER]

Abstract: The prevailing perspectives and definitions of risk, at least in the engineering community, are based on probabilities. In this paper we argue that such perspectives and definitions are too narrow. The probability component of the risk concept should be replaced by uncertainty. By jumping directly into probabilities, important uncertainty aspects could easily be overlooked or truncated. In the paper we point at several extended risk definitions, and a formal structure for the various perspectives and definitions is developed. Fundamental concepts such as second-order probabilities and uncertainties are discussed. Examples are provided showing the importance of the choice of risk perspective in a risk assessment and decision-making context. The examples cover offshore operations, security and market price risks. [Copyright &y& Elsevier]

Psychologists and philosophers who pose moral dilemmas to understand moral judgment typically specify outcomes as certain to occur in them. This contrasts with real-life moral decision-making, which is almost always infused with probabilities (e.g., the probability of a given outcome if an action is or is not taken). Seven studies examine sensitivity to the size and location of shifts in probabilities of outcomes that would result from action in moral dilemmas. We find that moral judgments differ between actions that result in an equal increase in probability of harm (equal size), but have different end-states (e.g., an increase in harm probability from 25% to 50% or from 50% to 75%). This deviation from expected value is robust under separate evaluation, and increases when the comparison between shifts is made explicit under simultaneous evaluation. Consistent with the centrality of perceived harm in some models of moral judgment, perceived harm partially mediates sensitivity to location of harm probability shift. Unlike for shifts in harm probabilities, participants are insensitive to the location of shifts in probability of beneficial outcomes. They are also insensitive to the location of shifts in probability of analogous monetary losses and gains, suggesting an asymmetry between harm and benefit in moral reasoning, as well as an asymmetry between moral and monetary decision-making more broadly. Implications for normative philosophical theory and moral psychological theory, as well as practical applications, are discussed. [ABSTRACT FROM AUTHOR]

Wildfire is a natural element of many ecosystems as well as a natural disaster to be prevented. Climate and land usage changes have increased the number and size of wildfires in the last few decades. In this situation, governments must be able to manage wildfire, and a risk measure can be crucial to evaluate any preventive action and to support decision-making. In this paper, a risk measure based on ignition and spread probabilities is developed modeling a forest landscape as an interconnected system of homogeneous sectors. The measure is defined as the expected value of losses due to fire, based on the probabilities of each sector burning. An efficient method based on Bayesian networks to compute the probability of fire in each sector is provided. The risk measure is suitable to support decision-making to compare preventive actions and to choose the best alternatives reducing the risk of a network. The paper is divided into three parts. First, we present the theoretical framework on which the risk measure is based, outlining some necessary properties of the fire probabilistic model as well as discussing the definition of the event 'fire'. In the second part, we show how to avoid topological restrictions in the network and produce a computable and comprehensible wildfire risk measure. Finally, an illustrative case example is included. [ABSTRACT FROM AUTHOR]